Healthy Food & Healthy Living by Dr. Ayala

The health and weight of the (young) nation

It has been many a pediatrician’s nightmare prediction: rising obesity rates are likely to cause an increase in type 2 diabetes in teens, in much the same way these two conditions are linked in adults.

And this fear has come to pass. Type 2 diabetes, unheard of in kids just a few decades ago (it used to be called adult-onset-diabetes for just that reason!), has become unexceptional in pediatric practice.

But what we’ve seen so far seems to be just the tip of the iceberg. A new article in Pediatrics looked at a group of about 3400 nationally representative teens (aged 12-19), and found that diabetes and pre-diabetes nearly tripled in less than 10 years, jumping from 9 percent in 1999-2000 to 23 percent in 2007-2008.

The authors, led by Ashleigh May, warn that these results should be interpreted cautiously: Diabetes and pre-diabetes were diagnosed by a single fasting blood sugar test. The true prevalence of type 2 diabetes in kids is hard to know unless blood tests are done because the disease can have little or no symptoms for a very long time. The numbers do look high, and it’s going to be interesting to see if other large-population studies corroborate them.

Teens at serious cardiovascular risk

High blood sugar wasn’t the only cardiovascular risk factor facing the teens in the study. Overweight and obesity were common – 16 percent of the kids were overweight and another 18 percent were obese.

On top of that, 14 percent of kids had pre-hypertension or hypertension, 22 percent had borderline or high LDL (bad) cholesterol, and 6 percent had low HDL (good) cholesterol.

All these above mentioned risk factors were seen much more frequently among the kids with overweight and obesity, in fact, among obese teens 61 percent had at least one cardiovascular risk factor on top of their weight status, and 8 percent of the obese teens had 3 or more of the tested risk factors. But even among normal weight teens 37 percent had a cardiovascular risk factor (the most common of which was high LDL), showing that even when teens aren’t overweight they can benefit from interventions promoting a better diet and more physical activity.

A bit of good news if I may: it seems like obesity rates have leveled off and they haven’t changed much during the 9 years covered in this study. For overweight and obesity to level off at a third of the pediatric population is of little comfort, though

Diabetes in teens carries extra burden

Kids with diabetes not only have more years to accumulate the disease’s serious complications – the longer one has diabetes the more likely heart, kidney, eye, nerve and other body systems are to suffer its consequences. Type 2 diabetes is also proving to be much harder to treat in young patients according to recent studies.

It doesn’t have to be so!

I assume that the vast majority of the kids in this study had pre-diabetes – a condition that if left unattended can, and often will, develop into diabetes (the article doesn’t differentiate between diabetic and pre-diabetic teens). But pre-diabetics can reverse their metabolic state with just modest weight loss and exercise.

And for all of us, type 2 diabetes is mostly a lifestyle disease. It is really up to us to feed kids better and help them become more active so they’re not doomed to develop totally preventable disease and disability as young adults.

What to do? HBO’s excellent Weight of the Nation looks at this complex issue in depth and with compassion. If you haven’t seen it yet, I highly recommend the Children in Crisis chapter (I actually think it’s a good idea to watch the chapters out of order – I found the first installment, Consequences, to be so depressing that I have a feeling some viewers might have just given up on both the series and on dealing with obesity before that chapter was over).

As Dr. Tom Frieden, CDC director, says: The weight of the nation is not healthy. And to get it healthy, we’re all going to have to do our part.

 

Dr. Ayala

 

Preschoolers suffering nature and exercise deficits

A happy day is one in which some time is spent outdoors.

Dog owners take their dogs out daily, and pediatricians suggest we extend the same kindness to our kids.

No, seriously, kids need the outdoors quite critically. Outdoors translates to physical activity and fitness, and the more time kids spend outdoors the less likely they are to become obese. Kids don’t exercise in gyms; they have bursts of intense, vigorous, heart racing activity while playing in a large open space, when they’re chasing a friend or a squirrel, or repeatedly going up and down a slide. Playing outdoors also helps kids’ development and growth and does wonders to their vision, coordination, vitamin D levels and mood!

Experts say that free play — especially outdoors — is crucial to a kid's health, but chances to play outside have been on the decline over the past few decades. Busy lives, over anxiety about safety, screen based entertainment and lack of awareness are keeping kids indoors.

Not enough outdoors time

A new study in the Archives of Pediatrics & Adolescent Medicine looked at the frequency at which parents took their kids to play outside. The authors, led by Pooja Tandon, used a nationally representative sample of about 9,000 4-year-olds, whose parents were asked how often they took their kid out to play. 

They found that about half of the preschoolers were taken out by their parents daily.

Is another caregiver taking these kids out? Possibly — daycares are supposed to take kids out. But even among the 20 percent of children in the study who didn’t attend any day care or preschool at all, only 58 percent went outside daily with mom or dad.

Is safety the issue?  

An important barrier to spending time outdoors could be perceived or actual concern for safety. This study found that the vast majority of parents thought that their neighborhood was either very safe (58 percent) or fairly safe (35 percent), with just 5 percent assessing their area as fairly unsafe and only 2 percent as very unsafe. So dangerous neighborhoods were not the issue.

Has TV replaced playing outdoors? The researchers found that the 4-year-olds in the study spent almost 4 hours a day in front of a screen — which is a lot, and almost double the (generous) American Academy of Pediatrics’ suggested upper limit — nevertheless, screen time wasn’t correlated with how often parents took their kids out to play.

There was also no correlation with household income or mom’s marital status. 

There were, however, two interesting variables that increased the odds of getting regular fresh air: boys were taken out more often than girls, and moms who exercised regularly were more likely to the take their kids out.

It seems like active parents raise their kids to be more active, and perhaps the known statistic that boys are generally more active than girls can be partly explained by the fact that boys are given more opportunities for activity. 

Get outside!

Being active starts at home and with the parents.

Barring dangerous weather, kids — and adults — I do believe, will do themselves some good by spending some time outdoors every day. Regardless of what happened at day care or school, parents should encourage kids to go out, run around, look at trees and birds, meet some insects, get dirty and come back tired. I can’t think of a better way to take a break from work, media and chores than to leave them all behind and go out with the kids. Soon enough these young kids will be able to enjoy the outdoors without adult supervision, and if you’ve collected some great outdoor memories you’ll be rewarded with outdoor enthusiasts for life.

Dr. Ayala

“Sunshine is delicious, rain is refreshing, wind braces us up, snow is exhilarating; there is really no such thing as bad weather, only different kinds of good weather.” ~John Ruskin

 

Can we blame our habits for making us fat?

We’d like to think we’re free to make choices about our everyday life.

But studies show that almost half of the actions people take each day aren’t actually a result of decisions – they’re driven by habit alone.

Habits are so strong and so ingrained that they override many other thought processes. It seems like our human brain, trying to save on energy, goes into autopilot for every process it can use old routines for, and will fight any proposed change. The positive side of habit is that once you’ve mastered dressing up in the morning and backing out of your garage, your mind can wander free while you’re performing a rather complicated task. The negatives are quite clear to anyone trying to lose weight or stop smoking.

Charles Duhigg’s "The Power of Habit" is a fascinating exploration of the research of habits, and is packed with absorbing stories about how habits influence every aspect of our lives – the way we shop, listen to music, drive, and of course eat is driven mostly by habit. Understanding habits is the key to creating change.

The habit loop

A habit is a three-step loop, written in our brain’s pathways. First comes a cue: a trigger that tells our brain to go into the automatic mode of the habit. Then comes the routine, which is the physical, emotional or mental action we take. What follows is the reward: the prize at the end of the routine is what reminds our brain why this habit is worth keeping. When a habit is fully formed the reward’s rush of excitement appears well before it actually happens – brain scans show that we expect the reward and get excited as soon as the cue appears, and this anticipation creates cravings.

Food habits start innocently: Feeling tired or bored an hour after lunch can become a cue to walk to the vending machine and select a high calorie snack that hits all the right spots and gives you the instant reward of yumminess and energy. After repeating this routine several times it becomes habit, and your brain craves to finish the loop whenever the faintest prompt shows up. 

Watching TV acts as a cue for many people to munch: the cue is the TV or the couch, the routine is going through a bowl of chips, and the reward is that physical sensation of this delightful combo experience. The loop becomes so automatic, that watching TV without a bowl of munchies makes you feel robbed (and in case you forget it there’s always an ad to remind you that watching is better with eating).

Advertisers are well aware of the psychology of habit, and if you examine carefully, many ads and marketing campaigns build a habit loop in which they tie a certain cue – be it a place, an emotion, a time of day, a thought or a situation – to the action of consuming their product and feeling its reward. Duhigg uses McDonald’s as an example of habit building strategy:

“Every McDonald’s looks the same – the company deliberately tries to standardize stores’ architecture and what employees say to customers, so everything is a consistent cue to trigger eating routines. The foods at some chains are specifically engineered to deliver immediate rewards – the fries, for instance, are designed to begin disintegrating the moment they hit your tongue, in order to deliver a hit of salt and grease as fast as possible, causing your pleasure centers to light up and your brain to lock in the pattern. All the better for tightening the habit loop.”

Keystone habits

Some habits are more important than others, because they spill over to other parts of life, causing a ripple effect. These habits are called keystone habits and identifying them can often trigger widespread change.

Take exercise: Studies show that introducing exercise – even infrequently – changes other daily routines. Unknowingly, people who start to exercise start eating better, are less stressed, and become more productive at work. Duhigg lists eating dinner as a family as a keystone habit, which seems to go with better homework skills, higher grades, better self-control and more confidence.

I’d argue that sugary drinks are a keystone habit that initiates an array of associated poor nutrition habits. That’s one of the reasons most serious diet programs target the sugary drink habit first – winning the soda habit change leads to several other wins that follow.

Is habit destiny?

Once a fresh sheet of paper has been folded it will tend to fold into the same crease, and once water carved a path in the soft soil water will naturally flow in the same route, but our habits are malleable, and as Duhigg concludes:

"Once you know a habit exists, you have the responsibility to change it...others have done so...That, in some ways, is the point of this book...how we eat and sleep and talk to our kids, how we unthinkingly spend our time, attention and money — those are habits that we know exist. And once you understand that habits can change, you have the freedom and the responsibility to remake them. Once you understand that habits can be rebuilt, the power of habit becomes easier to grasp and the only option left is to get to work."

Changing habits is very hard work, and thinking about the power of established habit should remind us to be aware of habit acquisition, especially as parents.

We can do our kids a favor by helping them acquire good habits – habits that ensure that their automatic, default routines are healthy and beneficial. If kids brush their teeth every night before bedtime, get used to healthy eating habits, learn how to cook and are active when young they’re likely to continue doing these things throughout life.

We should also do our best to help them avoid habits that will be difficult to fight later on. Highly processed, densely caloric salty sweet and fatty foods are addictive and habit forming – ads make them even more so. Eating while multitasking, constant snacking and eating in the back seat of a car are learned routines that will not serve them well.

Dr. Ayala

“It is easier to prevent bad habits than to break them” ~Benjamin Franklin 

Reposted as part of Food Renegade's Fight back Fridays. 

Flat Belly Tip: Eat More Fiber

Not all body fat is created equal.  Some people accumulate fat predominantly in the belly, while in others fat deposits are spread all around, and it does matter, because belly fat presents a higher risk for chronic diseases.  Think of belly fat as a big, active endocrine gland secreting risky substances — abdominal or visceral fat is especially active metabolically and plays a part in insulin resistance and diabetes, lipid abnormalities, hypertension and cardiovascular disease. 

And here’s another piece of worrying news: The majority of Americans are now overweight or obese, and the extra padding we’ve added as a population has accumulated preferentially in the worst location for our health — our belly — and even people with normal weight seem to be getting wider waistlines.

Why are bellies getting disproportionately bigger? Some ethnic groups — such as Asians, Indians and Hispanics — have a higher tendency to accumulate abdominal fat. Other factors suggested to affect belly fat buildup include lack of exercise.

But does our diet affect where we deposit our fat stores?  Does the kind of food we eat determine body shape?

Lifestyle and belly fat

Several studies suggest that sugary drinks and fructose increase fat accumulation in the worst possible locations of our anatomy.

A new study in the journal Obesity followed 1,114 people over 5 years, looking to see if lifestyle factors directed fat preferentially to the belly.

The study population included 339 African Americans (African Americans tend to have lower belly fat than whites or Hispanics) and 775 Hispanic Americans, aged 18-81 years.   Participants were asked about their dietary and exercise habits, weight and height were measured at baseline and follow-up visits, and belly fat was measured with an abdominal CT scan.  A CT scan is a rather invasive way to measure belly fat, but a very accurate one.

Of all the foods and nutrients considered in the study one single nutrient was most significantly associated with belly fat: Fiber.  For every 10 grams of soluble fiber eaten per day, belly fat was reduced by about 4 percent after 5 years -- irrespective of total weight or BMI. 

Other studies have shown that reduced fiber diets are associated with weight gain, but this study actually showed that soluble fiber makes fat “choose” a depot that’s healthier for us — if you overeat, but eat more soluble fiber, the fat will go under the skin, rather than into the belly.

Oh, and here’s one more important finding: Vigorous exercise was also associated with less belly fat. 

Fiber: soluble, insoluble, and where to find it

Dietary fiber is a part of plant food that we humans cannot digest, but it nevertheless has many health benefits.

Soluble fiber is fermented by bacteria in the gut and has physiologically active byproducts; insoluble fiber is metabolically inactive, and just absorbs water and creates bulk as it moves through the gut, thus speeding food’s passage in the gut and preventing constipation.

Both soluble and insoluble fiber may help in making us feel full on less food, because they add to food bulk while adding no calories.  Soluble fiber has shown promise in lowering LDL (bad) cholesterol, regulating blood sugar and prevention of heart disease.  Insoluble fiber aids regular bowel movement.

Good sources for soluble fiber include fruits such as apples, bananas, plums, and berries, vegetables such as broccoli and carrots, sweet potatoes and onions, legumes such as soy, peas and other beans, and grains such as oats and barley.

Good sources of insoluble fiber include whole grain foods, bran, nuts and seeds, vegetables such as celery and zucchini, and the skins of many fruits and veggies.

Most Americans get only about 15 grams of fiber per day in their diet, which is half the minimum 25-30 grams recommended.

What about fiber supplements and foods with fiber added to them? It’s unclear if added fiber provides the benefits of naturally occurring fiber and the benefits of supplements have not been studied as extensively as those of dietary fibers – the food plant as a whole is usually more than the sum of its known parts.

Fiber for a flat belly

All fruits, veggies whole grains and nuts contribute fiber to our diet.  I don’t participate in the fiber wars, and wouldn’t favor one fruit over another for its fiber quantity or quality.  If you eat your fruits and veggies you’ll get plenty of fiber – but do try to leave the peel on where appropriate.

Eating fruits and veggies reduces the risk of obesity, but this new study suggests that eating them also enables us to direct where were we deposit our fat even if we do gain weight — dietary fiber may funnel that fat to a more favorable storage area.

Dr. Ayala 

 

Does The Biggest Loser Fuel Weight Stigma?

Overweight people are the majority in the US; a third of Americans are obese, so obese people can hardly be viewed as a small minority.

Nevertheless, overweight people face bias and discrimination every day.

Does the portrayal of obese people in the media reinforce weight bias?  Is the swelling roster of popular weight-loss reality TV shows supporting anti-fat attitudes? Or do these shows actually introduce viewers to the trials and tribulations of obese people, thus promoting sympathy and reducing prejudice? 

NBC’s The Biggest Loser is now in its 13th season and is a huge hit, with millions of viewers weekly, an online weight loss program, a line of diet and nutritional supplements, and two weight loss resorts.

The Biggest Loser clearly promotes weight loss, but some suggest that the show presents the unrealistic view that enormous weight loss can be achieved by willpower and very hard work – suggesting obesity is totally controllable. 

A new study in the journal Obesity examined how a 40-minute episode of The Biggest Loser affected viewers' anti-fat attitudes.

About 60 undergraduate students participated in the study, in which they were randomly assigned to watch an episode of The Biggest Loser or a nature film, while being told that the purpose of the study is to test the effect of media consumption on processing speed.  The participants’ attitude was gauged before and after the reality TV show by several established tests, developed to check for anti-fat sentiment, stereotypical attribution traits and bias.

Increased negative attitude

Watching The Biggest Loser (sans ads) did not improve attitudes towards obese people.  It made them worse.

The participants who watched The Biggest Loser reported greater dislike of obese people and greater belief that weight is controllable.

Since The Biggest Loser’s contestants show enormous commitment, hard work and perseverance, the researchers expected to see a change in anti-obese attitudes, and a shift in the positive traits attributed to obese people.  This did not happen. 

Does controllability translate to blame?

We tend to have greater compassion for conditions that are beyond human control, and spare less sympathy for what we believe are troubles that are entirely under the individual’s power to change. If the take home message from The Biggest Loser is that weight loss is entirely a matter of hard work and overcoming obstacles, we can see how internalizing that idea would increase weight bias.  This study’s incendiary findings should be taken with a grain of salt though, due to the small study group composed of all young students – its authors advise as much. 

The reality of weight loss doesn’t make for compelling reality TV, I’m afraid.  Tara Parker-Pope’s recent article “The Fat Trap” tells the stories and the science behind why losing weight -- and especially keeping it off -- are beyond what most people are able to do. Although Parker-Pope’s article was widely spread I wonder how many TV viewers would tune in weekly for that kind of pessimistic analysis.

It’s complicated, but although we ultimately decide what and how much we put into our mouths obesity and overweight aren’t completely under most people’s control. Most people don’t want to be fat and are indeed spending lots of energy, time and money to get thinner. The fact that we have an obesity epidemic that is evident even among preschoolers indicates that gluttony and laziness don’t explain what's going on.

That’s not to say that weight loss is something we should give up on, but clearly, the only true, far-reaching solution to overweight is unsexy prevention – which of course doesn’t tell a compelling story, since averted trouble creates no drama at all.

Dr. Ayala

 

Childhood obesity: Prepare for the flood

In contrast to adults, chest pain in kids is rarely of cardiac origin. A new article in the journal Pediatrics reassures us that an aching chest in kids, although a common complaint, was only rarely due to abnormalities of the heart.

But is the growing epidemic of childhood obesity threatening to change that? Could obesity in childhood result in heart attacks and other cardiovascular events when those children hit their 20s and 30s and even when they’re still teens?

Dr. David Katz’s piece in Childhood Obesity last year starts with a scary prediction, a prediction he hopes will never come true. 

Katz, an internist and leading authority on nutrition, weight management and the prevention of chronic disease, director and founder of Yale University's Prevention Research Center, warns that heart disease might become a routine pediatric condition.  Heart disease can follow the path of type 2 diabetes, – previously called “adult onset” diabetes, because it was an affliction of adults – which is spreading among kids like an epidemic and is diagnosed in obese kids under the age of 10 years.

Dr. Katz tells us that in adults, guidelines for healthcare providers suggest that any patient with diabetes should be treated as if they have some degree of heart disease, because diabetes is such a strong risk factor for coronary artery disease. 

Can we assume the same for kids?  Kids who’ve had diabetes for 10 years have been exposed to the damages this disease causes to blood vessels, and Katz suspects we’re going to see more and more kids in their late teens with chest pain and heart attacks.  He’s personally encountered a 25-year-old who’s had coronary angioplasty and a 17-year-old who’s had a triple bypass.

Stack a sandbag today

Katz is announcing this grim prediction so that action will be taken to prevent it from materializing.

We know what causes childhood obesity.  Overconsumption of all the wrong foods and lack of physical activity are now the default way of life for so many of our kids.  We live in an obesogenic environment, which is going to deluge us with disease.  To prepare for the rising tide and to block its toxic water we need, Katz suggests, any sandbag we can find:

“Programs that provide routine physical activity throughout the school day are a sandbag. Nutrition education is a sandbag. Cafeteria makeovers are a sandbag. Adding sidewalks to a neighborhood is a sandbag. Nutrition information on menu boards is a sandbag. Worksite wellness programs are a sandbag. Reliable nutrition guidance systems in the supermarket are a sandbag. Recognizing that neither children nor adults will get healthy unless both do, together, is a sandbag.

The flood waters are both menacing and high. Stacking sandbags to raise a levee is hard work—but it’s not complicated. So seize the moment; embrace the opportunity in this crisis. Stack a sandbag today. The child you save from our new-age plague might be your own.”

Whenever a solution is proposed critics are quick to scrutinize and announce, quite correctly, that it will not solve the obesity crisis.  But if we can’t stop the flood and dam the mighty river should we dismiss sandbags? I completely agree with Katz: The sandbags needn’t be perfect, but we do need many of them and a joint effort to stack them up real high.

Dr. Ayala

More from David Katz here.

 

Fat burning miracles?

A few years ago billboards announced the arrival of “negative calorie” food.  Drinking three 12-oz. cans a day of Enviga, the Coca Cola and Nestle carbonated tea drink, will burn an extra 60-100 calories daily, claimed the products’ packaging.

The Center for Science in the Public Interest (CSPI) filed a lawsuit against Coke for Enviga’s false weight-loss claims. Coke and Nestlé agreed to add language to the labels and marketing materials stating that the product will not promote weight loss without diet and exercise and Enviga is slowly vanishing from shelves.  But supplements and foods claiming to slim you down have not – they are alive and thriving.

A new paper in Obesity Reviews looks at the dynamic market of nutritional supplements claimed to increase fat metabolism, and explores how much evidence – or lack of it – is behind some of these popular supplements.

What is a ‘fat burner’?

A fat burner is a substance that is claimed to increase energy expenditure, make you lose weight, or somehow promote fat breakdown.  Many fat-burning supplements combine several ingredients, claimed to work in concert.  Is there such a thing as a fat burner?  The article examines some of the most popular such miracles, and I’ll discuss just a few of those.

Fat burners on the market

Caffeine

The ultimate functional ingredient, caffeine appears naturally in coffee, tea and cocoa and is also added to many foods and drinks.  Anyone who drinks coffee knows that coffee does have active ingredients that increase alertness – that’s why I love my morning cup.  It makes loose dreamy words stick into lucid sentences.  But does it increase energy expenditure and promote weight loss? 

A few studies showed that high doses of caffeine increased metabolic rate, however, longer-term studies tracking dieters taking caffeine or placebo showed caffeine performing no better than the dummy pill.  Overall, the authors conclude:

“Caffeine on its own has not been shown to be effective in reducing body weight and if caffeine increases fat metabolism, the effects are generally small”

Carnitine

Carnitine, which occurs naturally in meat, and is produced by our own liver and kidneys, is claimed to improve fat metabolism and increase muscle mass. 

Most of the carnitine in our body is in our muscles, and our muscle takes up carnitine from our blood against a huge concentration gradient (sorry for the flashback to high school chemistry, but it’s needed in order to understand how little sense this makes).  Studies have shown that the enzyme that is responsible for transferring carnitine into the muscle is at maximum capacity, and therefore ingesting extra carnitine doesn’t raise muscle carnitine at all.

The only way in which muscle carnitine could be elevated was by increasing blood levels of both carnitine and insulin at the same time – by insulin intravenous drip or very large amounts of ingested sugar.  This impractical scenario is quite counterproductive from the weight-loss point of view.

Carnitine supplementation for weight-loss just doesn’t make sense!

Tea

Tea contains catechins, which are thought to stimulate fat metabolism.  Green tea, which is non-oxidized and non-fermented tea leaves, has especially high levels of catechins, the most interesting of which is EGCG (epigallocatechin 3-gallate).  The authors review the green-tea weight burning studies and find them inconclusive:

“Green tea has the potential to increase fat metabolism at rest, also during exercise, and may help to lose body fat and body weight.  As with caffeine, the effects appear to be relatively small…”

Chromium

Chromium is added to many “functional” foods and drinks (Vitamin Water, Fuze) and is sold as part of many supplements as a fat burner and muscle builder.  Chromium occurs naturally in broccoli, red wine, mushrooms, brewer’s yeast, wheat germ and other foods, and was reported to increase lean body mass during exercise. 

The excitement was dampened by further, better studies that found chromium had no effect – overall, the majority of studies find it useless – and the authors also caution that a few studies on cell cultures found chromium can cause chromosomal damage.

Want to burn calories?

The authors, A. E. Jeukendrup and R. Randell, conclude with an overall impression that most of the supplements marketed as fat burners have little or no science to support their claims, and that among the group, caffeine and green tea have some effect, but it is small, and more consistent in habitual caffeine users.  They write:

“The ever increasing list of fat-burning supplements is industry driven, and is likely to grow at a rate that is not and cannot be matched by similar increase in scientific underpinning” 

In other words, marketers are quick to announce miracle solutions based of the flimsiest of evidence collected on a few lab mice or a cell culture; if and when the science manages to amass enough research that more often than not doubts the substance’s merit, sellers are already quick to market with the next new fat-burning sensation.

How can we end this? Silly and optimistic as I am, I’m hoping for an end to health claims on foods and supplements.  Health claims were introduced in 1994, have been so miserably abused and have become so utterly misleading that it’s just time to say goodbye. 

The other more realistic way is that consumers will start rejecting the hype and express their skepticism with their wallets.

Let’s end with the age-old solution to fat burning.  We know it works.  It’s healthy and inexpensive, too.  It’s called exercise.

Dr. Ayala

 

Can healthy neighborhoods reduce the risk of diabetes?

Do you live in a healthy neighborhood?

Is there such a thing as an unhealthy neighborhood?

Personal choice has a big impact on many aspects of our health, but do we really have the wherewithal to choose our lifestyle, or do most of us fall into a pattern determined by what’s easy to do and what everyone else is doing? Sure, there are a few motivated individuals who swim against the stream and set their own trend. Most of us don’t. Whether we realize it or not, we follow the lead of our parents and friends and do what’s easy, along a path of least resistance.

There’s no doubt that our collective lifestyles have changed dramatically in the past decades. Convenience is everywhere—we do less physical work around the house, we drive a lot, and cheap highly processed calorie-dense foods are everywhere. 

But as I’m sure anyone driving through urban and suburban neighborhoods observes, there are great differences between regions. Some neighborhoods have green spaces, joggers, bikers, kids playing outside and farmer's markets and supermarkets with colorful inviting fresh produce. Not far away there are neighborhoods where all life is within four walls, fresh food sources are limited and corner and convenience stores are the sole resource for food.

Can a neighborhood influence health?

That’s a question researchers led by Amy Auchincloss set out to answer in a recent paper in the Archives of Internal Medicine. They wanted to see if neighborhood’s physical attributes and the availability of healthy food affected the incidence of type 2 diabetes.

The researchers followed 2,285 people, aged 45-84 years at baseline, from three different regions in the US for five years for the development of diabetes. Among the data collected was income, assets, educational level, family history, smoking status, body mass index (BMI), exercise level and dietary measurements.

The data on neighborhood resources was obtained from an independent sample of the participants’ locales (not from the study population). The residents were asked if their neighborhood was easy or pleasurable to walk in, has ample opportunity for physical activity, or if they see other people jog or play sports. The food environment was determined by asking whether there’s a large selection of fresh fruits and vegetables available, whether produce is high quality, and whether there’s a large selection of low-fat products available.

During follow-up, 233 of the study participants (about 10 percent) developed type 2 diabetes.

And the result: Better neighborhood resources for food and exercise were associated with lower incidence of type 2 diabetes

• Participants living in great neighborhoods for activity and healthy food had 36% less chance of developing type 2 diabetes than their counterparts living in neighborhoods with poor resources for activity and healthy food. 

• After adjusting for individual variables—such as age, family history of diabetes, socioeconomic status, smoking, physical activity and dietary factors—the environmental association persisted.

• The association was slightly reduced after also adjusting also for BMI.

The authors conclude:

“The prevalence of type 2 diabetes has increased substantially in the past 30 years. This makes it all the more urgent to identify environmental features that may mitigate risk of type 2 diabetes. Our results are consistent with the hypotheses that improving environmental features—such as having nearby, pleasant, safe destinations within walking distance and improving the availability of healthy foods—may halt increases in type 2 diabetes incidence. Many urban environments have developed with insufficient consideration for the ways that environments can promote or discourage healthy behaviors. 
Current efforts to foster health-promoting environments include designing and modifying physical environments, such as zoning residential neighborhoods to require safe sidewalks, creating parks and attractive public green spaces, and improving public transportation so that residents rely less on their cars; supporting fresh-food farmers' markets in low-income, urban neighborhoods; and assisting stores in those neighborhoods in improving their selection of healthy foods. 
There is unlikely to be a panacea for the obesity epidemic and rising epidemic of type 2 diabetes. However, altering our environments so that healthier behaviors and lifestyles can be easily chosen may be one of the key steps in arresting and reversing these epidemics.”

An accompanying editorial by Mitchell Katz discusses how hard it is to tease apart environmental and individual behavior influences on health. This study is by no means the last word on this complicated issue. But Katz sees us all as participants in a huge multinational study of the impact of the structural environment on diabetes.

In the past 50 years we in the developed world have stopped walking, our household chores are now reduced to pushing a button, fast food and super-sized meals replaced our food, and processed foods are easier to find than fresh fruits, vegetables and whole grains. And while a cause and effect is hard to prove, Katz sees this grand experiment going really badly—these environmental changes coincide with skyrocketing rates of obesity and diabetes all around the developed world.

Katz calls for a change in our environment, one that would make exercise and eating right much easier and more routine.

What do you think of your neighborhood? Does it promote health or encourage unhealthy habits?

Dr. Ayala

Flat Belly Tip: Eat More Fiber

Not all body fat is created equal.  Some people accumulate fat predominantly in the belly, while others’ fat deposits are spread all around, and it does matter, because belly fat presents a higher risk for chronic diseases.  Think of belly fat as a big, active endocrine gland secreting risky substances -- abdominal or visceral fat is especially active metabolically and plays a part in insulin resistance and diabetes, lipid abnormalities, hypertension and cardiovascular disease. 

And here’s another piece of worrying news: The majority of Americans are now overweight or obese, and the extra padding we’ve added as a population has accumulated preferentially in the worst location for our health — our belly — and even people with normal weight seem to be getting wider waistlines.

Why are bellies getting disproportionately bigger? Some ethnic groups — such as Asians, Indians and Hispanics — have a higher tendency to accumulate abdominal fat. Other factors suggested to affect belly fat buildup include lack of exercise.

But does our diet affect where we deposit our fat stores?  Does the kind of food we eat determine body shape?

Lifestyle and belly fat

A new study in the journal Obesity followed 1,114 people over 5 years, looking to see if lifestyle factors directed fat preferentially to the belly.

The study population included 339 African Americans (African Americans tend to have lower belly fat than whites or Hispanics) and 775 Hispanic Americans, aged 18-81 years.   Participants were asked about their dietary and exercise habits, weight and height were measured at baseline and follow-up visits, and belly fat was measured with an abdominal CT scan.  A CT scan is a rather invasive way to measure belly fat, but a very accurate one.

Of all the foods and nutrients considered in the study one single nutrient was most significantly associated with belly fat: Fiber.  For every 10 grams of soluble fiber eaten per day, belly fat was reduced by about 4 percent after 5 years – irrespective of total weight or BMI. 

Other studies have shown that reduced fiber diets are associated with weight gain, but this study actually showed that soluble fiber makes fat “choose” a depot that’s healthier for us – if you overeat, but eat more soluble fiber, the fat will go under the skin, rather than into the belly.

Oh, and here’s one more important finding: Vigorous exercise was also associated with less belly fat. 

Fiber: soluble, insoluble, and where to find it

Dietary fiber is a part of plant food that we humans cannot digest, but it nevertheless has many health benefits.

Soluble fiber is fermented by bacteria in the gut and has physiologically active byproducts; insoluble fiber is metabolically inactive, and just absorbs water and creates bulk as it moves through the gut, thus speeding food’s passage in the gut and preventing constipation.

Both soluble and insoluble fiber may help in making us feel full on less food, because they add to food bulk while adding no calories.  Soluble fiber has shown promise in lowering LDL (bad) cholesterol, regulating blood sugar and prevention of heart disease.  Insoluble fiber aids regular bowel movement.

Good sources for soluble fiber include fruits such as apples, bananas, plums, and berries, vegetables such as broccoli and carrots, sweet potatoes and onions, legumes such as soy, peas and other beans, and grains such as oats and barley.

Good sources of insoluble fiber include whole grain foods, bran, nuts and seeds, vegetables such as celery and zucchini, and the skins of many fruits and veggies.

Most Americans get only about 15 grams of fiber per day in their diet, which is half the minimum 25-30 grams recommended.

What about fiber supplements and foods with fiber added to them? It’s unclear if added fiber provides the benefits of naturally occurring fiber and the benefits of supplements have not been studied as extensively as those of dietary fibers – the food plant as a whole is usually more than the sum of its known parts.

Fiber for a flat belly

All fruits, veggies whole grains and nuts contribute fiber to our diet.  I don’t participate in the fiber wars, and wouldn’t favor one fruit over another for its fiber quantity or quality.  If you eat your fruits and veggies you’ll get plenty of fiber – but do try to leave the peel on where appropriate.

Eating fruits and veggies reduces the risk of obesity, but this new study suggests that eating them also enables us to direct where were we deposit our fat even if we do gain weight -- dietary fiber may funnel that fat to a more favorable storage area.

Dr. Ayala 

Reposted as part of Food Renegate's Fight Back Fridays -- join the food fight!  

The dos and don'ts of colorectal cancer prevention

Cancer of the colon and rectum are the third most common cancer in the world, accounting for 10 percent of cancer overall. Colorectal cancer is correlated with industrialization and is more common in higher income countries. In fact, a rise in its incidence usually coincides with the spread the western diet and lifestyle – Japan, Singapore and Eastern European countries experienced a doubling of colorectal cancer rates in the last few decades – therefore nutrition and lifestyle have always seemed to play a big part in increasing the risk for this often deadly disease.

The World Cancer Research Fund is a non-profit that funds scientific research on cancer prevention and promotes healthy living. A new authoritative report from its Continuous Update Project reviewed the current research papers (hundreds of them), weighed the evidence, and came out with an analysis of what we can all do about reducing our risk of colorectal cancer.

Reducing risk, increasing protection

The expert panel found convincing, consistent and cumulative evidence for several modifiable factors:

Probably protect against colon cancer:

• physical activity

• foods containing dietary fiber – the data is about fiber contained in food naturally, not fiber supplemented to food or in supplements

• garlic, milk, and calcium – evidence not as strong as the factors mentioned above, but still quite convincing

Probably increase risk of colon cancer:

• consumption of red meat and processed meat – this is a dose-response relationship, the more red/processed meat the higher the risk

• alcoholic drinks (by men and probably by women)

• body fatness and abdominal fatness – abundant and consistent evidence that obesity, and especially increased belly fat, are a serious risk factor

For other factors the panel found that the evidence is limited and only suggestive of a cancer causing effect:

Maybe protective foods:

• non-starchy vegetables
• fruits
• foods containing vitamin D

Maybe risky foods:

• Foods containing iron
• cheese
• foods containing animal fats
• foods containing added sugars

A plant based diet for cancer prevention

Although cancer is a disease caused by many factors – genetic predisposition and environmental exposures to name just a few – experts agree that many cases of cancer can be prevented. Scientists estimate that by eating healthy, being physically active and maintaining a healthy weight we can prevent about a third of the most common cancers.

What is healthy eating? This report, like many others points toward a more plant centered diet as the best description of what eating well is at its essence.

There is no compelling evidence to convince even me (full disclosure: I am a lifelong vegetarian) that meat in moderation causes cancer or any other disease, but there’s no doubt that half a pound of meat a day – which is what the average American eats – is way too much.

The highly processed food and fast food diet (which can easily be called the fiber-less diet) is definitely the riskiest way to eat when it comes to colorectal cancer, and it plays a role in numerous other ailments, too.

This weekend marks the official beginning of barbeque season, so how about a few more veggies on that skewer?

Dr. Ayala

Reposted as part of Food Renegate's Fight Back Fridays--go join the food fight!

Does thinking about exercise make you eat more?

Exercise burns calories. We’d all love to believe that we can forgo the unpleasant recommendation to eat less if we committed to exercising more – and the biggest fans of the “move more” doctrine are the makers of calorie-dense processed foods.

And while there are so many compelling reasons to exercise — regular physical activity reduces heart disease, diabetes and hypertension, boosts mental health, fosters strong muscles and strong bones and improves our looks — exercise alone rarely results in weight loss.

One of the obvious reasons for the disappointing weight-loss outcome of an exercise alone regimen is that physical activity increases appetite, and we quickly reimburse ourselves for the calories spent with calories eaten.

Just thinking about exercise makes us eat more

A new study in the journal Appetite has an even more downbeat finding: Just thinking about exercise — without ever moving a muscle — may make us eat more.

The study group included 94 people shopping in a mall in the Northeastern US. People were asked about their shopping habits, exercise habits or music listening habits (to mask the study’s true intent).

After answering the initial questions the test subjects read a scenario describing either a fun 30-minute walk, or a 30-minute exercise walk. The control group just answered questions about shopping.

Once questionnaires were completed the participants received what they thought was a token of gratitude for their time and effort, but what was really the main measured outcome of the study. The participants were offered as-much-as-you’d-like ChexMix and M&M’s which they scooped into bags.

The people who read the 30-minute walk scenario poured about 60 percent more M&M’s and 52 percent more ChexMix into their thank you bag. It didn’t matter if the walk was described as a “fun” walk or a strenuous walk — both groups compensated themselves by additional snacks compared to the control group.

Overcoming calorie compensation

Advanced exercise equipment quantifies the number of calories spent working out — it’s actually more a guess than a true measurement. If exercise is perceived as permission to eat the treadmill's calorie calculator may be its worst feature.

So how do we decouple exercise and eating? The authors, led by Carolina Werle, suggest we stop presenting physical activity as a route to weight-loss, and present it as a method to improve muscle tone, improve posture, strengthen bones and improve health. Exercise should be pursued as a goal in and of itself, rather than a means to an end (the end goal being weight-loss).

Some of my food loving friends who are super committed to exercise claim that exercise enables them to enjoy food in a less restricted way, while maintaining their weight. I think that attitude works quite well.

So many of us enjoy watching sports, and I’d be really curious to see if watching other people involved in physical activities increases consumption. What do you think? Does watching sports make you eat more?

Dr. Ayala

Reposted as part of Food Renegate's Fight Back Fridays--go join the food fight!

Can video games be a tool for better nutrition and more exercise?

I’m very old fashioned when it comes to video, computer and all other electronic games. OK, I’ll admit it: I don’t even fully understand why playing them is fun, or as my kids say, I just don’t get it. My imaginary migraine-inducing chamber-of-torture is a video arcade – but that’s just my personal inclination, and I’m in the minority. According to the Kaiser Family Foundation’s recent survey kids spend an average 7 hours 38 minutes a day in front of a screen. A typical kid spends 65 minutes a day playing video games, and the majority of kids have a game console in their bedroom. So I guess video games are entertaining.

But spending hours in front of a screen is one of the least desirable uses of a kids’ time, and there’s plenty of evidence to back this assertion. The American Academy of Pediatrics recommends limiting screen time to less than two hours a day, and keeping screens out of the bedroom. That’s because screen time’s usually sedentary, and is linked with obesity and metabolic risk factors. Prolonged screen time is also associated with inferior academic performance.

Hours of inactivity are only one harmful outcome of sitting in front of a screen. Here’s another reason why screen time can make kids fat: Advertisers look for eyeballs wherever they can find them, and screen time, whether it’s TV, video, hand-held or computer, is soaked with ads. Guess who’s willing to pay top dollar to get your kid as a loyal customer for life? Fast-food and junk-food makers top the chart of kid oriented ads in electronic media.

There’s another really sad outcome of electronic games: Kids aren’t playing the way they used to. Kids’ play is the unstructured, messy, imaginative way in which kids create an inner world, interact with the real world, interrelate with friends, negotiate, solve problems, and work as a team. An old bed sheet becomes a toga, which turns into a sultan’s turban, which doubles as a magic carpet that can transport the princess to the castle (the castle’s roof made of the same cloth). A vivid example of child play is depicted in Toy Story 3 (one of the best movies I’ve seen this year). Kids’ play is a healthy way for kids to learn so much of the skills they’ll need, while having serious fun, and often while breaking a sweat.

Video games to the rescue?

Active video games debuted a few years ago, and my kids were excited to inform me that the Wii gets you moving and that “everyone has them” (to which I said: That’s great! you’ll be able to play them at your friends’ house).

Exergames indeed get you moving. Somewhat moving. A recent review in the Archives of Pediatric and Adolescent Medicine looked at these games and concluded that they enable light to moderate physical activity. To put it in other words, the Wii is better than sitting on the couch, but won’t improve aerobic fitness — to improve fitness kids need intense exercise and real sports, the kind that gets them sweating and their heart racing. Perhaps the groups that can benefit most from these exergames are patients undergoing physical rehabilitation and the elderly.

I asked my kids recently if the Wii’s still popular among their friends, and their conclusion was that the Wii gets rather boring after a while — and once a kid has a gaming console he’ll find something more exciting to play.

Here’s another attempt to make gaming healthy. A new study published in this months’ issue of the American Journal of Preventive Medicine examined the effect two epic video games, “Escape from Diab” and “Nanoswarm: Invasion from Inner Space”. These games incorporate behavior change procedures woven into the gripping stories, and were designed to improve diet and increase physical activity and were especially planned to lower risks of type 2 diabetes and obesity.

The 103 Kids playing these video games did increase their fruit and veggies intake when compared to kids playing diet and physical-activity knowledge-based games on popular websites, but only by about half a serving a day. They did not drink more water or engage in more physical activity (as measured by an accelerometer), nor did they improve body composition.

There are hidden messages in any programming. If the hero in a film smokes it may glorify smoking , yet if he eats vegetables it might make veggies cool. That’s what’s so good about Popeye. So by all means, I’m all for trying to get the right subliminal messages in. Every little bit helps.

The good, the bad and the violent

Video games are just a medium. Any medium can be used for good or bad. A better video game is possible — there are educational and active games, just like there are excellent TV programs — but they are the exception that proves the rule.

I hope you’re not feeling too sorry for my kids. They don’t have a gaming console — they’ve stopped asking for it — and we strictly limit screen time. But, could these kids play! They have an amazing capacity to play with each other and with friends, and whether it’s in the sun outside or on a cold day inside, they never fail to come up something wonderful to do.

Dr. Ayala

Sleep Yourself Thin?

“A good laugh and a long sleep are the best cures in the doctor's book.” ~Irish Proverb

Eat fewer calories and exercise more – that’s the age old recipe for weight-loss – the rest is gimmicks. But a new study suggests that we should perhaps add one more element to the regime: Get a good night’s sleep.

Sleep is one of the central pillars of good health. Sleep is absolutely critical to keeping us sane and happy. Yet we don’t give sleep as much respect as it deserves.

Several studies have shown a link between obesity and lack of sleep, but the association by itself doesn’t give much of a clue as to which came first and doesn’t prove causality. Obesity can cause sleep problems (the most serious of which is obstructive sleep apnea). Being awake at night can increase appetite and night-time-snacking (which usually isn’t green salad), and sleep deprivation can lead to poor food choices and inactivity.

But this new study in the Annals of Internal Medicine isolated the effect of sleep quite nicely; it looked at overweight adults on a weight-loss diet, and showed that all other things being equal, lack of sleep hindered the dieter's ability to shed excess body fat.

The study recruited ten overweight healthy adults who were fed a moderate calorie-restricted diet. Dieters were randomly assigned to sleep either 5.5 hours or 8.5 hours each night, for two weeks on each regimen, in a closed clinical research environment. The researchers measured weight, but also measured body fat directly (using dual-energy x-ray absorptiometry or DXA), so they could calculate how much of the weight-loss was loss of fat, and how much of it was lean tissue or muscle loss. The results in this small group were quite clear:

• Overall weight loss was similar whether the dieters slept 5.5 hours or 8.5 hours

• Sleep restriction resulted in more loss of muscle and less loss of fat: More than half the weight lost during the 8.5 hours sleep condition was fat, compared to just one quarter in the 5.5 hour sleep condition.

• During the two weeks of sleep restriction, dieters felt hungrier

Can a good night's sleep help preserve muscle during weight-loss?

When we ingest fewer calories than we expend – which is what happens on a weight-loss diet – the body goes looking for energy stores, and will break down both fat and protein to make sugars for energy.

The goal of any diet is to lose fat, not muscle. Not only do we like our muscle’s look and strength, muscles are active metabolically and burn energy, and loss of muscle during weight-loss diets is part of the reason people who've lost weight are so prone to regain it, and actually need to consume fewer calories just to keep their new weight stable. Preserving muscle is one of the reasons there’s such an emphasis on exercise during a weight-loss diet – working those muscles and building them is protection from dwindling muscle mass and slow metabolism. (For the sake of preserving muscle-bulk it’s also a good idea to avoid extremely low-calorie and nutritionally unbalanced weight-loss regimens.)

So a regime that protects muscle and leads to more fat-loss is very valuable. But don’t get excited just yet: This study involved only ten healthy participants, studied for a short while. But if results are confirmed by other studies this finding could be very important.

How could sleep affect fat loss? The researchers measured the levels of the hormone ghrelin and found that when dieters where on the sleep deprivation regimen ghrelin levels rose. Ghrelin, they reason, has been shown to signal hunger, reduce energy expenditure, hinder the breakdown of fat and increase the liver’s production of sugar. In this calorie deprived state of high ghrelin, the liver needs to make sugar while fat stores aren’t really open for providing building blocks, so it will break down muscle to fill the demand. There are, of course, many other possible ways in which lack of sleep may hamper fat-loss: fatigue may cause a dieter to be less active, and move less, for example.

Sleep isn’t a waste of time

Sleep is precious. Sleep isn’t always easy to get. Some people suffer from insomnia. Some work night shifts. Some have babies that make life look like a
night shift. But for those of us for whom going to bed late is just a habit, I think it’s time to rethink sleep. I used to turn in after midnight – for no particular reason – it made me feel that there are bonus hours to my day. When I moved to the street I live on now I was surprised to see that most homes were dark by 10:30pm. I asked my neighbors what the lights-out was all about; they were astonished by the question. The thought of going to sleep at 10:30 never occurred to me, but I gave it a try, and was absolutely shocked by what a difference it made to my general well-being.

If you’re sleep deprived give sleep a try. Adequate sleep is underappreciated, and I believe it to be one of the most important ways to achieve optimal health. I’ll be curious to see if further studies confirm sleep’s role in fat-loss.

Dr. Ayala

Related posts:
Three healthy habits to fight childhood obesity
The recipe for a long and healthy life

*As of next week I’ll be posting regularly on Wednesdays instead of Mondays.

Reposted as part of Food Renegate's Fight Back Fridays--go join the food fight!

Fatter, in all the wrong places

The fact that the majority of Americans are overweight isn’t any news. But here’s a worrisome new finding: The extra padding we’ve added as a population has accumulated in the worst location for our health — our belly — and even people with normal weight seem to be getting wider waistlines.

A new study led by Helen Walls in the research journal Obesity looked at trends of both BMI and waist circumference, comparing the data of two US national surveys, one held in 1988-1994, and the other in 2005-2006. Overall, the study looked at the measurements of almost 20,000 nationally representative adults, and found that bellies expanded disproportionately during the decade and a half studied.

Short intro to BMI and waist circumference:

BMI (body mass index) is a screening measure for overweight, useful for studying populations, and calculated by dividing the weight in kilograms by the square of height in meters. It doesn’t differentiate between fat and muscle, but BMI correlates quite well with body fat in most people. A BMI of above 25 categorizes people as overweight, and above 30 as obese.

Waist circumference simply measures the waist at the top of the hip bone. A waist circumference of more than 40 inches for a man and more than 35 inches for a woman is considered as “increased risk” for chronic diseases affected by obesity (lower cut-off numbers are suggested for certain ethnic groups, such as Asians).

Here are the study’s main findings:

• Between 1988-1994 and 2005-2006 the mean BMI increased by 1.8 kg/m2 to 28.7 kg/m2 (BMIs above 25 kg/m2 are categorized as overweight)

• Between 1988-1994 and 2005-2006 the mean waist circumference increased by 4.7 cm or 1.9 inches

• During the decade and a half between studies waists widened over and above what would have been expected by BMI

• Waist circumference increased in all weight categories of people younger than 50 years: The waists of people with normal BMI’s went up too, and there were substantially more normal weight men and women with “increased risk” waist circumference in the later study.

• Waist circumference went up in all ethnicities, education levels, and for both men and women

BMI doesn't tell the whole story

The researchers warn that by using BMI as a single tool to monitor the population’s obesity we may be underestimating the risk burden of obesity related disease.

Indeed, several studies have shown that belly fat is much more risky than general obesity and that fat distribution patters do matter. Belly fat or “visceral fat” is the fat deposited between the abdominal organs, is especially active metabolically and plays a part in insulin resistance and diabetes, lipid abnormalities, hypertension and cardiovascular risk. Think of it as a big gland, secreting metabolically active signals.

And perhaps, fitting into your old tight jeans is a better measure of healthy weight than the number on the scale.

Why are bellies getting disproportionately bigger? Some ethnic groups — such as Asians, Indians and Hispanics — have a higher tendency to accumulate abdominal fat, but this study found the trend of widening waists held even after stratifying by ethnicity. Other factors suggested to affect belly fat buildup include lack of exercise, over-intake of sugars, sleep deprivation, aging, imbalanced hormones, being male, stress and certain drugs.

What’s clear is that we don’t get to choose where our fat is deposited. Unfortunately, no amount of sit-ups will make a fat belly go away (the overlying muscles will get stronger, but the fat inside won’t dissolve preferentially in the exercised areas).

So what to do about abdominal fat? Eating a healthy diet and adequate aerobic exercise can prevent the buildup of belly fat, and losing weight will shrivel it. The good news is that visceral fat is lost preferentially with even modest weight loss — belly fat is the first to go when you lose weight!

Dr. Ayala

Another apple-a-day may save more lives than the Toyota recall

Many health organizations, including the World Health Organization and the National Cancer Institute, recommend five servings of fruit and vegetables daily to help ward off disease.

Some people (I’m not one of them) go even further and propose that eating enough fruits and vegetables provides strong protection from cancer.

Cancer is a complex group of diseases. We still know very little about what causes some cancers, but it’s probably safe to say that increased risk for most cancer types usually stems from a combination of factors—some genetic and environmental, which are hard to control, and some that we have much more power over. Smoking, exercise, obesity, diet and sun exposure have all been shown to affect cancer risk.

A healthy lifestyle has many components, and I personally don’t believe any one healthy diet habit by itself—even if practiced religiously over a lifetime—has a hugely dramatic effect on cancer incidence in a population.

Having said that, every little bit helps, and while we shouldn’t exaggerate any intervention as the “solution” to cancer, these small measures together do add up and help prevent some disease.

That, by the way, is why I see all health claims on food as at least a little misleading. The diet-health relationship is real, but is always more complicated and variable than what a simplistic statement implies.

A new study in the Journal of the National Cancer Institute got quite a lot of coverage in the past few days; it found what the authors called only a weak association between high fruit and vegetable intake and reduced overall cancer risk. The headlines in many news publications (“Eating Vegetables Doesn’t Stop Cancer " in the New York Times, “Fruit and vegetables have little effect on cancer risk, study finds ” in The Guardian) suggested deep disappointment over fruits and veggies’ “poor performance” against cancer.

Is this a blow to the five-servings-a-day advice? Let’s first take a closer look at the study.

Paolo Boffetta of the Mount Sinai School of Medicine in New York and colleagues analyzed data from the EPIC study (European Prospective Investigation into Cancer and Nutrition), which included almost 500,000 participants from ten Western European countries. In about nine years of follow-up, more than 30,000 participants were diagnosed with cancer.

The authors found a small but statistically significant association between high intake of fruits and vegetables and reduced overall cancer risk--the higher the intake the lower the risk.

The data shows a 3 percent lower risk of cancer for every 200 grams, or seven ounces, of fruits and vegetables a day a person eats. People who ate five or more servings a day had 11 percent fewer cancers than those who ate 0-1.5 servings a day.

These results were consistent across the countries studied.

Higher intakes of fruits and vegetables in this study group were associated with other healthy behaviors, such as smoking avoidance, limited alcohol consumption and exercise, which may also be protective from cancer. But the small protective effect of fruits and veggies persisted even after adjusting for these factors.

How significant is 3 percent protection from cancer?

Numbers are often hard to understand without context—they aren’t as absolute as they sound. Is 3 percent a small number?

There is of course no one right answer to that.

Let’s take a look at the Toyota recall and compare risk/benefit ratios.

The chance of an owner of a recalled Toyota experiencing a deadly acceleration problem is assessed at 2.8 in a million. (There were 17 fatal accidents related to acceleration in 10 years, before six million cars were recalled. New complaints are now pouring in, which is quite typical after a recall and law suits are announced.) But we all expect Toyota to recall and fix all relevant cars, and we’re angry they failed to address this problem sooner.

The yearly cancer incidence in the U.S. is estimated at 4,600 in a million; one and a half million Americans are diagnosed with cancer each year, and 1,500 die of cancer daily. If, as this study suggests, eating an additional seven ounces a day of fruits and veggies can reduce cancer incidence by 3 percent we’d have 40,000 fewer Americans receiving the diagnosis of invasive cancer yearly.

In Toyota's case we demand action when the current risk is as small as 2.8 in a million, yet with cancer, where the disease risk is as high as 4,600 in a million, some suggest that a reduction of 3 percent in risk does not make much of a difference.

I wouldn’t perhaps recommend a drug with many side effects if it reduced a rare disease’s risk by 3 percent, but for an “intervention” as benign as eating an additional apple a day, and a disease as serious and common as cancer a 3 percent risk reduction looks like a decent size reward.

What if fruits and veggies offer no protection from cancer?

When a study shows only a small difference in outcome between the studied groups, there’s also the possibility that this difference can be explained by chance, and by something other than the variable studied. In this case we have to bear in mind that eating more fruits and veggies is generally associated with a healthier lifestyle, and no matter how hard the authors try to control for the other healthy lifestyle factors, some bias may remain.

So even though this study and several others show a probable small reduction in all-cancer risk, let’s bear in mind that it’s also possible that eating your veggies might offer no significant protection from cancer.

Yet, this “worst case” scenario still leaves us with many excellent reasons to continue promoting fruits and veggies. Here’s a partial list of good reasons to eat plenty of fruits and vegetables:

• They help lower the risk of heart disease and stroke (a study showed a 30 percent lower risk in people eating five servings a day, compared to those who eat only 1.5 servings a day)

• They help lower blood pressure

• They help lower diabetes risk

• They help lower risk of eye (cataract and macular degeneration) and digestive (constipation and diverticulitis) problems

• They provide lots of fiber, both soluble fiber, which helps lower cholesterol and regulate sugar, and insoluble fiber, which is important to digestive health

• They provide vitamins, minerals and many other beneficial plant molecules—phytonutrients—many of which we’re only starting to understand. (And I’m sure there are a few we have yet to discover. My mom knew nothing about lycopene, for example, when she fed me tomatoes and watermelon.)

• They have high nutritional value and low caloric density, so eating many fruits and vegetables (rather than practically any other food) helps lower caloric intake and maintain optimal weight

• They taste good, are beautiful to look at, and connect us to nature

My last item on the virtues list is completely non-objective; I’m guilty of total fascination with colorful growing things that we can also eat.

If, in all the years that fruits and vegetables have been consumed and studied, the worst we can say about them is that they’re not as thick a shield against all cancers as some had hoped, this speaks to just how good for us they really are.

So keep those fruits and veggies coming!

Dr. Ayala

Reposted as part of Food Renegate's Fight Back Fridays--go join the food fight!

This entry has been posted as part of The Kathleen Show's Prevention not Prescriptions