Healthy Food & Healthy Living by Dr. Ayala

Battle of the diets: Which is best for your heart?

Misinformation is a common problem when it comes to diet advice – it spreads through diet books, blogs and social media outlets such as TikTok, Instagram and Twitter. According to Christopher D. Gardner, the director of nutrition studies at the Stanford Prevention Research Center, misinformation has reached critical levels, leading to widespread confusion about what we should eat to prevent disease and promote health.

To help us make sense of the barrage of diet messages we receive, a team of scientists, cardiologists, health experts and dietitians headed by Gardner evaluated common diet plans to determine how they comply with evidence-based guidelines for promoting heart health. Their findings appear in the journal Circulation.

So let’s start with what we know promotes heart and metabolic health: We should eat plenty of vegetables and fruit, prefer whole to refined grains, choose healthy proteins, mostly from plants, but also from fish and seafood, and if consuming meat and poultry avoid processed and fatty forms, prefer plant oils to animal and tropical oils, limit ultra processed foods, minimize sugary drinks and foods with added sugars, and moderate alcohol intake.

The best and the worst

The panel identified 10 popular diet plans. These include (1)  DASH  (Dietary  Approaches  to  Stop  Hypertension)-style, (2) Mediterranean-style, (3) pescetarian,  (4)  ovo/lacto-vegetarian,  (5)  vegan,  (6)  low-fat,  (7)  very low-fat, (8) low-carbohydrate (including Zone, South Beach, low glycemic), (9) Paleolithic (Paleo), and (10) very low-carbohydrate/ketogenic patterns (which includes Atkins and the ketogenic diet). For the several vegetarian style diets the researchers considered optimal versions of the diets – chips and soda are vegan, yet don’t represent a plant-based diet, as eating more plants is a central tenet of this food philosophy. Same applies to the other diet plans.

They then compared these popular diets to the ideal diet as defined by the American Heart Association’s dietary guidelines. Diets were ranked using a 0-100 point system.

And the results: 

The best diets are Mediterranean, DASH-Style, pescetarian, and ovo/lacto-vegetarian diets. They score high (above 85 points) because they emphasize vegetables, fruit, whole grain, healthy oils and moderate alcohol intake. They are also flexible, providing a wide range of choices. They also score high on sustainability, and have a lower environmental impact.

The lowest scoring diets: Paleo diets and very low carb/ketogenic diets with a score of under 55 points. Following these diets doesn’t align as well with dietary guidelines. These diets are promoted for weight loss and the notion that carbs are bad is widespread, but painting carbs with a broad brush eliminates healthy carbs, such as fruits, vegetables, legumes and whole grains, the cornerstone of a healthy diet. So although the Atkins and keto diet restrict some foods that should be limited, such as added sugar and refined grains, they miss the point on many other healthy, whole, fiber-rich plant based carbs, and introduce lots of animal products and fatty meats.

Taking the long view

Although the ketogenic and low carb diet may curb appetite and lead to short term weight loss, they’re not a good long-term plan. These diets often increase “bad” cholesterol levels, which can elevate the risk of heart disease, they impose a strain on the kidneys, and they’re difficult to maintain long term due to their restrictiveness. “A diet that’s effective at helping an individual maintain weight loss goals, from a practical perspective, needs to be sustainable,” says Gardner.

The Keto and paleo diets not only have a lower dietary quality, they also have a higher carbon footprint according to a recent study in the American Journal of Clinical Nutrition. The keto diet, which is a high-fat low-carb diet, is estimated to produce almost 3 kg of carbon dioxide for every 1,000 calories of food. The paleo diet, which prioritizes meats, nuts and vegetables, emits 2.6 kg of carbon dioxide for every 1,000 calories. A vegan diet, on the other hand, generates 0.7 kg of carbon dioxide per 1,000 calories – less than a fourth of a keto diet.

Common sense would suggest that it’s moderation that’s key to a sustainable, healthy diet. 

The sensible, practical, socially acceptable diet plan you can keep long term is the most promising plan for weight control and for wellness. 

Dr. Ayala

 

Do babies naturally hate Kale?

A new study about kale-hating fetuses captured the imagination in popular media recently. The research, published in Psychological Science, scanned about 100 pregnant women using 4D (3D made into a video) ultrasound after exposing them to vegetables, and showed more smiling fetuses after exposure to carrots, and more “cry-faces” after mom-to-be ate kale. The ability to code 4D ultrasounds and visualize the curve direction of the corner of a fetus’ mouth in the third trimester results in stunning images – cuteness factors in to make these findings more shareable, and that’s perhaps why this study made it into the Today show.

These aren’t surprising findings though. 

Many pregnant women say that their fetus reacted to certain foods they ate, perked up soon after they had a dose of their favorite flavor, and also liked the same food as a baby.

These anecdotes are supported by theoretical plausibility and some evidence. We know that a fetus develops taste buds early on in pregnancy, that the nose passages (where the organ of smell resides) are open, and inhale amniotic fluid by the end of the second trimester.  Even though the flavor and aroma receptors are not fully developed, and the fetal brain interpretations of the senses are immature, exposure to the content of the amniotic fluid does occur. We have evidence that flavor molecules, originating from mom’s diet, are present in amniotic fluid. There are also studies that show that exposure to certain flavors in pregnancy increases the chance the baby will like these flavors better once they’re introduced to new foods, in the second half of their first year of life.

As to the babies displeased with mom’s food choice: prenatal exposure may lead to better acceptance of kale later in life, and that’s something on which "future studies need to follow up,” the researchers conclude.

It’s never too early

Humans are innately fond of sweet food. But natural preference is just a starting point, as we’re creatures of instinct, but also of habituation and learning. As with many natural tendencies, a parent’s role is to modulate these in order to form healthy, adaptable behaviors in their kid. And since when it comes to food only 1 in 10 kids eat enough veggies, focusing on acquiring a flavor preference for veggies could be very beneficial.

These smiling and frowning 4D ultrasound babies are a reminder that it’s never too early: Mom’s diet during pregnancy, and if she’s breastfeeding, after birth, exposes the baby to the flavor of veggies from the very beginning, well before they eat their first pureed tomato. 

Food habits are one of these things in which timing really matters, as there’s a window of greatest opportunity to take advantage of. Generally, a baby’s first 20 months are the time they’re most open to new flavors and textures – bear in mind that babies are usually fed nothing but milk until age 6 months. Acceptance of new foods decreases after that, food neophobia (dislike of the unfamiliar) peaks at age 5 years, after which interest in new flavors and textures usually recovers.

Say yes to vegetables

Taking advantage of the high adaptability of the very young makes for a good head start with loving your veggies. 

A review, in Appetite, looked at 46 relevant scientific studies – 25 interventional studies and 21 observational ones – on promoting intake of vegetables in kids under 3 years of age. 

Repeated exposure (for 8-10 repeats) was the focus of 27 studies. All 21 experimental studies find that recurrent exposure increases intake, usually by at least about an ounce a day, and that the younger the baby, the greater the gains in veggie consumption. The 6 observational studies confirm the same trends. Some of these studies had up to 6-month follow up, demonstrating that repeated exposure led to a stable uptick in veggies.

Pay attention to the amount of repeats in these studies: Although there is a chance of success by the third exposure, it usually takes many repeats to change a baby’s mind and by the eighth exposure about 70 percent of babies will like a veggie they previously disliked. The persuasive power of repetition works on a baby the way it works on us – hence the repetitive messages and ads we shown.

And bear in mind that many things we eventually love to eat are an acquired taste – think coffee, cheese that smells like sweaty feet, garlic, hot sauce  and wine.

Exposure to a variety of veggies also seems to increase veggie intake in young kids in the 15 studies examining this strategy. When variety is piled on to repeated exposure the advantages are magnified.

Setting a veggie-loving example also helps. Parents who eat vegetables in the presence of their kids tend to have kids that eat vegetables. Three observational studies in the above review confirm that setting a good example of eating and enjoying vegetables is associated with higher frequency and intake in their young kids. And that makes sense: Most kids eventually eat their parents’ diet.

It’s never too late to fall for veggies. Try to do so yourself if it hasn’t happened to you yet; there’s lots of flavor and beauty to explore in the veggie kingdom. The finest chefs in the world are demonstrating their newly found veggie infatuation through vegetable tasting menus – why, Eleven Madison Park recently retained its 3 Michelin star status after going plant-based. Serve veggies in a positive, calm, fun, no pressure way. It also follows common sense that better-tasting, nicely prepared veggies will be better liked.

Soon enough, your kids may like kale.

Dr. Ayala

Is what’s better for the planet also better for you?

Climate change is a pressing issue, and mitigating it may demand some personal sacrifices. Our food system and dietary choices are linked to climate change because food production contributes about one third of greenhouse gasses worldwide. 

Some diets contribute more greenhouse gasses than others.

Some food patterns pose more chronic disease risk than others.

Are carbon footprint and disease risk aligned?

Production of animal foods emits more greenhouse gasses. Beef production emits 10 times more than chicken, and 20 times as much as growing legumes, nuts and seeds. We also know that diets high in red and processed meat are linked with higher risk of heart disease, cancer and overall earlier death.

There are very few studies about the relationship between diet, environment and health, according to researchers from Tulane University, led by Donald Rose, and some of the data relies on specific populations, such as Seventh-Day Adventists, who are not representative of the general population, as their lifestyle and demographics aren’t just a choice of plant-based diets. The researchers set out to check personal health/planet health relationships in a representative population. The study appears in the journal Public Health Nutrition.

The researchers looked at the diet of almost 13,000 nationally representative Americans aged 18-64 years. Each diet’s greenhouse gas was calculated. The researchers used a well established diet mortality tool called PRIME (the Preventable Risk Integrated ModEl), which estimates the number of lives that can potentially be saved by behavior changes – such as diet, exercise, smoking and alcohol – in a population. They then simulated what would happen if they moved the population from the highest carbon emitting diet to the lowest.

And the results:

Moving from a high to a low emitting diet would result in 24,000 lives saved a year, which is 2 percent less deaths in the US. Most of the lives saved in this simulation would be thanks to a reduction in heart disease deaths.

What would be causing the reduced risk of death on the low carbon diet? The low carbon diet has more plant foods and less beef.

The results of this study concur with another study from the United Kingdom, which simulated a transition to a less-meat diet, and found a reduction in deaths lined up with the reduction in emissions – the more meat is substituted with plants the more lives saved.

The authors conclude: “This provides additional evidence that diets which are environmentally less impactful are also more healthful and suggests that efforts to implement more environmentally sustainable dietary patterns in the USA could also reduce mortality from CVD (cardiovascular disease).”

Another study in the journal Climatic Change estimated how even small changes to the diet affect both greenhouse emissions and health. The researchers looked at the risk of diabetes, colon cancer and heart disease, and in the simulation model, a diet’s red and processed meat content was progressively swapped with legumes, grains, fruits and vegetables. The model did not alter added sugar, dairy, eggs or fish. The healthier diet models reduced the risk of heart disease, colon cancer and type 2 diabetes by 20-45 percent while dropping  greenhouse gas emissions 200-800 kg per person a year – depending on the relative shift to plant-based proteins.

No sacrifice at all?

While the percentage of vegetarians in the American population is in the small single digits, and that's unlikely to change, moving from a high meat diet to a lower meat diet can save many lives and improve personal wellness, while also improving our atmosphere.

Lowering the thermostat in summer, increasing it in winter, and cutting on driving may be a price we will each decide to pay in order to cut greenhouse gasses, but when it comes to food, what’s good for the planet will also do you some good personally. 

And eating more plants can be pleasurable – a plant-centric diet can be absolutely delicious, so culinary considerations need not suffer.

Dr. Ayala

Do vitamins and supplements really promote wellness?

How many vitamin bottles adorn your counter? Many Americans have quite a collection. Almost 80 percent of Americans report consuming daily supplements. The vitamin and supplement 50 billion industry spends 900 million on advertising. The barriers to entry into this lucrative business are low: the makers and marketers never had to prove efficacy, do not need FDA approval, and carefully crafted health and vigor declarations – that fall just a tad short from health claims – are exaggerated if not outright misleading, yet are legal. The vitamin and supplement industry receives very little oversight.

People are naturally concerned about filling nutritional gaps in their diet. People would also like to optimize their health and fitness. The vitamin and supplement marketing messages fall on receptive ears because who could say no to effortless prevention, enhancement, beauty and stamina. 

Vitamins and supplement additives are clearly useful for correcting vitamin and mineral deficiencies. Vegan diets, for instance, don’t contain enough if any B12 and need supplementation with this vitamin. Folic acid and iron supplementation is recommended during pregnancy – folic acid supplementation is proven to reduce the incidence of neural tube defects, and folic acid is advised for anyone pregnant or planning a pregnancy.

What about the rest of us?

Updated recommendations published by the US Preventive Services Task Force, an independent volunteer group of national experts in prevention and evidence-based medicine, sorted through the vitamin and supplement scientific data. The recommendations follow a systematic review of 84 studies, among them an additional 52 new studies since the previous review.

For healthy adults who are not pregnant, and not diagnosed with a deficiency, the US Preventive Services Task Force states that “current evidence is insufficient to assess the balance of benefits and harms of the use of multivitamin supplements, single supplements, or most paired supplements for the prevention of cardiovascular disease or cancer.”

The task force specifically recommends avoiding beta carotene (possible increased risk of heart disease and lung cancer) and vitamin E supplements. 

As to multivitamins: there’s “insufficient” evidence, the task force concludes.

The appeal of the pill

In a new editorial in JAMA scientists from Northwestern University support the new recommendations.

The authors start with the well supported fact that “eating fruits and vegetables is associated with decreased cardiovascular disease and cancer risk.” It’s reasonable to assume that if key components of the fruits and vegetables can be extracted and compacted into a pill these pills would do the same, at lesser effort and expense.

Alas, fruits and vegetables can’t be mimicked by a pill, as plants contain a myriad of compounds: besides the known vitamins and minerals, also fiber, phytochemicals, and many more micronutrients, working in concert. We (that includes the microbes living within us) have co-evolved with plants and are adapted to metabolize these foods. 

What’s the harm?

If it won’t help, it can’t hurt, is what many say as they pop in a bunch of vitamins.

The task force begs to differ.

As mentioned above, there was increased risk of lung cancer among smokers who took beta carotene supplements. Taking vitamin A may reduce bone density. Vitamin D supplementation can cause high blood levels of calcium and kidney stones. 

Beyond that, supplements are a waste of money and  – even worse – squandered attention, states the Northwestern physicians editorial, led by Jeffrey Linder, MD. “Rather than focusing money, time, and attention on supplements, it would be better to emphasize lower-risk, higher-benefit activities. Individual, public health, public policy, and civic efforts should focus on supporting people in regular preventive care, following a healthful diet, getting exercise, maintaining a healthy weight, and avoiding smoking.”

Real food is the best source of nutrients, and plant foods are more than the sum of their known nutrients. Decades of controlled studies of vitamin and mineral supplementation have been largely disappointing.

Although eating well and exercising isn’t always easy, the multivitamin and supplement “insurance policy” may be standing in your way to committing to improving your diet.

Dr. Ayala

No meat, low meat, and what really matters for health

The calls to cut back on meat are coming from many directions. The meat industry is a major contributor to greenhouse gasses, climate change, and environmental degradation. Billions of animals suffer and die to satisfy our eating choices.

These altruistic reasons to cut down on meat come on top of the self-serving rationale to do so: Eating less meat is good for you.

Studying the outcomes of a lifetime of dietary habits is difficult – the range of what and how much a person eats is extensive and diets change over time – but decades of research show that the risk of cardiovascular disease is overall lower among vegetarians and vegans. Vegetarians and vegans tend to be thinner, have lower total LDL cholesterol, and lower blood pressures. 

A link between meat and cancer is also well studied. The American Cancer Society recommends limiting or avoiding red and processed meats in order to lower the risk of cancers. The World Cancer Research Fund states that if you eat red meat, shoot for no more than 3 portions (12-18 oz cooked weight) a week, and consume very little if any processed meat.

Low meat, fish, and vegetarian diets and cancer risk 

As noted from the above recommendations, it’s not just vegetarians that can lower their disease hazard, as the risk from meat is cumulative and dose dependent.

A new study in BMC Medicine analyzed the nutrition data from almost half a million British adults, aged 40-70 years, and looked at the incidence of cancer over 11 years, also controlling for diabetes, socioeconomic factors, smoking and obesity.

About half (52 percent) of the cohort ate meat more than 5 times a week, 44 percent ate meat less than 5 times a week, 2 percent ate only fish but no meat, and 2 percent were vegetarian or vegan.

The study finds that those who ate meat less than 5 times a week had a 2 percent reduction in cancer incidence, fish eaters had a 10 percent reduction, and vegetarians and vegans had a 14 percent reduced risk. Low meat, fish and vegetarian eaters had lower risks of all-cause cancer, and especially colorectal, prostate and breast cancer.

But although the study controlled for confounders such as weight status and exercise, the authors note that: “Vegetarians and fish-eaters differ from meat-eaters in many non-dietary lifestyle factors such as lower smoking and alcohol consumption, and higher physical activity. Although relevant potential confounders were added to the multivariable models to adjust for these differences, imperfect measurements and/or changes in these confounders over time may result in incomplete adjustment for these variables.”

Not all meat-free diets are created equal

Not all foods of plant origin are healthy though: French fries, chips and soda are utterly vegan, and obviously don't promote health.

Meat avoidance, in and of itself, doesn’t tell us enough about what people actually eat, therefore studies that look at the content of plant-based diets are informative.

The longest living group of Americans are probably The Seventh Day Adventists, whose health habits—promoted by their religion—include vegetarianism, as well as avoiding alcohol and smoking. Adventists as a group aspire to these rules, and are generally health conscious, but individual adherence is variable, and not all adventists avoid meat. Studying and subgrouping this diverse cohort is revealing.

A new study in the American Journal of Clinical Nutrition following about 77,000 members of the Adventist church for about 7.5 years looked at their rates of death from any cause, and correlated it with how much ultra-processed foods and meat they ate. 

And the results: Eating more ultra processed foods was associated with a 14 percent higher incidence of death. Eating more red meat was also linked with an 8 percent increase in all cause mortality.

The quality of any diet is determined by what you eat more of, and also what you eat less of. 

Instead of categorizing a food just as plant-based you should also question its nutritional quality.

A recent study in the American Journal of Clinical Nutrition including almost 130,000 people, followed for 20 years, sought to see if  plant-based diets affect weight gain, which is an important risk factor for many chronic diseases.

The study uses three indexes of plant-based diets. The first is an overall plant-based index, in which plant-based foods receive a positive score, and animal foods receive a negative one. The other two are subcategories of the first one and rate the healthfulness of of the plant based components of the diet, adding points for healthful plant based foods (whole grains, fruits, vegetables, nuts, legumes, vegetable oils, tea/coffee) and reducing score for less healthy plant foods (sweetened beverages, refined grains, sweets/desserts).

Participants gained on average 2 to 4.5 pounds every 4 years. Diets that were more plant-based mitigated weight gain. But not all plant-foods and meat avoidance regimens fared equally: People who ate a more healthy plant based diet gained 1.5 pounds less. People who ate an unhealthy plant-based diet gained about 1 pound more.

Similar results are seen studying type 2 diabetes: Overall a high plant-based diet and especially healthy plant-based diets are linked with lower the risk of diabetes. Unhealthy plant-based diets, however, are actually associated with higher rates of type 2 diabetes.

And the same goes for cardiovascular disease: although sticking to a more plant-based diet seems to be protective, when examined more carefully the subgroups of plant-based eating patterns diverge – healthier plant-based diets are linked with lower heart disease risk, but an unhealthy plant-based diet confers a higher risk.

Watch out for highly processed food

As plant based meat and milk alternatives expand – clearly a blessing for animal rights and environmental benefits – make sure that you’re not replacing an eat-less-of ingredient with yet another one that we should watch for: highly processed food.

Many in the meat avoiding population are health conscious, and their wellbeing can be attributed to the myriad of healthy routines they practice, in diet, physical activity, mental wellbeing, smoking avoidance etc., all working in conjunction. 

Vegetables and plants are the essence of a healthy vegetarian lifestyle, meat avoidance alone doesn’t do the trick – and meatless burgers are hardly a plant.

Dr. Ayala

Does a healthy diet reduce the risk of severe Covid-19?

I haven’t written about Covid for a while. Frankly, I was hoping to move on to other health topics by now – we’ve been living under this shadow for almost two years. But Covid-19 is still a central health matter, and many of its mysteries remain unsolved.

One of the most puzzling issues is the incredible variability in disease severity, age notwithstanding. Underlying medical conditions, such as hypertension and diabetes predict a higher likelihood of severe disease, as does obesity, but there’s a lot that can’t be explained by that.

Could nutrition inform some of this disparity? Poor diet is linked with the severity of other infectious diseases. Sound nutritional status supports immunity, lowers the chance of severe, out-of-control inflammation, and malnutrition causes immune deficiency.

This question remains relevant for this pandemic. Although vaccination is the most effective way to prevent severe disease and hospitalization, breakthrough infections are possible and ameliorating those is vital – we’re not completely done protecting ourselves, even with two shots. 

This question is also crucial for other infectious diseases known and yet to come.

Diet and the pandemic

A new study in the journal Gut looks at data from almost 600,000 people in the UK and the US, who were followed from March to December of 2020 by the smartphone based Covid-19 Symptom Study. All participants’ diet was assessed before the study began.

During follow-up almost 32,000 people had Covid-19 infections.

Healthy plant-based diets were associated with lower risk of contracting the disease and of severe Covid-19.

Poor diet quality was associated with lower socioeconomic status, as you might imagine. Healthy behaviors tend to cluster and people who eat healthy may sign on to other health-promoting measures. 

But the association remained strong even after accounting for other healthy behaviors, social determinants of health like education disparities, income inequality, housing insecurity, healthcare access, social isolation, food insecurity, unemployment, public safety etc., and the steps taken to prevent virus transmission such as mask wearing as well as the rates of transmission of Covid-19 in the community.  The authors conclude that: “The joint association of diet quality with socioeconomic deprivation was greater than the addition of the risks associated with each individual factor, suggesting that diet quality may play a direct influence in COVID-19 susceptibility and progression. Our findings suggest that public health interventions to improve nutrition and poor metabolic health and address social determinants of health may be important for reducing the burden of the pandemic.”

Another study of about 3000 health workers from France, Germany, Italy, Spain, UK, and the US showed that those on a plant based or pescatarian diet had lower odds of moderate to severe disease after taking into account other health characteristics, with the vegetarians among the group showing a 73 percent lower chance of moderate to severe illness, and the pescatarians with 59 percent lower odds of significant manifestations.

Again, removing every confounder is impossible, but we already have so many reasons to invest in healthy diets – personally with our own decisions and with public health interventions that increase access and education about the importance of eating well. This isn’t just the Covid-19 pandemic: Poor diets are a risk factor for a long list of chronic diseases, from heart disease to diabetes to cancer.

Dr. Ayala

Fruits and veggies: It’s not just about vitamins

Eat more fruits, veggies and whole grains and minimize ultra processed food, this is the nutrition advice in a nutshell most health experts impart. Many interpret this guidance as the best way to consume lots of nutrients – such as vitamins and minerals – and to avoid overeating and weight gain.

It’s undeniably so. A healthy whole foods diet is one of the best ways to consume all the nutrients we need; it’s calorically less dense and more satiating than processed food. 

But there’s another important reason this diet is linked with lower risk of heart disease, diabetes and cancer: this may be the diet that supports a healthy microbiome.

Our microbiome is composed of the trillions of microbes within our body – bacterial cells outnumber our own cells tenfold. Gut microbes are involved in our immune modulation, they produce many necessary metabolites, including vitamins, antioxidants, and key short chain fatty acids. The environment that we create within our body is part of what determines which bacteria will thrive and which will decline.

Because lifestyle is the most important regulator of the microbiome. 

A study of more than 1000 people published in the journal Nature found that sharing genetic makeup mattered much less than sharing a diet and an environment, as just 2 percent of the gut microbiome is genetically determined.

Eating to feed good bacteria

Several studies have looked at the diet-microbiome connection. 

Greater adherence to a mediterranean diet pattern was associated with a beneficial microbiome pattern in a study of 153 Italians. There are several studies showing that vegans and vegetarians – who tend to eat more fruits and veggies – exhibit a more favorable microbiome.

A new study in the American Journal of Clinical Nutrition looks at a much larger population of almost 5000 Finnish people, and at their whole diet to see how gut microbes are affected. The study examined diets based on detailed food questionnaires, and those were scored for healthy food choices based on well established dietary guidelines. Microbiome diversity and species were characterized by studying stool samples. 

Healthier diet scores – those with more fruits, vegetables and whole grains – were linked with healthier microbiomes. Red and processed meat were associated with less diversity and fewer of the beneficial type microbes.

Dietary fiber may be one of the most important influences on gut microbiome flora in this study and in others. We depend on our bacteria to break down fiber, and the more fiber in the diet the healthier the microbiome.

For far too long people have looked at foods as the sum of its macro- and micro-nutrients, and believed that you can get away with eating poorly by supplementing with a multivitamin. But we shouldn’t view fruits and vegetables as just a vitamin source: we eat the whole thing because the whole is much greater than its (known) parts and because that’s the diet we evolved with. Fruits and veggies were known to be healthy before we discovered vitamins, and way before we developed nutrition science. The new revelations about the microbiome might help clarify one more aspect of plant-based foods benefits.

“The results of our study support the balanced plant-rich diet recommended by dietitians around the world,” the authors conclude.

Eating a whole foods plant centered diet promotes health in countless ways and plants’ secrets are slowly revealed – it probably also improves outcomes through a more diverse and beneficial microbiome.

Dr. Ayala

Not all plant-based is created equal

Whether you’re seated in a restaurant, scrolling social media feeds, or walking the supermarket aisles, the term “plant-based” will hit you soon enough. It’s everywhere.

Health professionals have been recommending a plant-based or a plant-forward eating pattern – foods that comes mostly from plants – for many decades. The recent plant-based trend explosion, however, is fueled by the meatless burger revolution. Demand for Beyond Meat and Impossible Burger patties has skyrocketed, and Beyond Meat’s IPO was incredibly successful. These products look and taste like meat, and enable people to eat a vegan burger with little sacrifice.

Which is good news for animals, as fewer cows will be factory farmed and slaughtered. It’s also very good news for the environment – raising cattle is a huge drain on land and energy resources, and destroys the ecosystem.

Now that plant-based hamburgers have become mainstream and can be found in fast-food joints and college campuses, are we also going to see a boon to public health?

Plant-based for health

Recommendations for plant-based diets are based on large studies– very many of them – that find that plant-centered and Mediterranean style eating patterns correlate with good health. Vegetarian and Mediterranean eating patterns are associated with reduced risk of heart disease, type 2 diabetes, hypertension and certain cancers, and also with lower rates of obesity and a longer life.

These eating patterns have a wide range of adherence and animal-product avoidance, but generally they focus on fruits, vegetables, nuts, seeds, whole grains, beans, and legumes. When health professionals recommend a plant-centered diet what they’re talking about is a healthy plant based eating pattern, or a whole-foods plant-based diet.

Because not all foods of plant origin are healthy: Potato chips and soda are perfectly vegan, and obviously not good for you.

And since meat avoidance, in and of itself, doesn’t tell us enough about what people actually eat, we need to look at studies that grade plant-based diets according to their healthfulness.

A new study in the American Journal of Clinical Nutrition looks at data from large cohorts such as the Nurses Health Study and the Health Professionals Follow-up, including almost 130,000 people, to see if plant-based diets affect weight gain. Overweight and obesity are important risk factors for many chronic ailments, therefore the link between plant-based diets and weight is an important health measure.

The researchers look at three indexes of plant-based diets. The first is an overall plant-based index, in which plant-based foods receive a positive score, and animal foods receive a negative one. The other two are subcategories of the first one: healthful plant based (whole grains, fruits, vegetables, nuts, legumes, vegetable oils, tea/coffee) receive positive scores, less healthy plant foods (sweetened beverages, refined grains, potatoes, sweets/desserts) and animal foods received reverse scores, and unhealthful plant-based (sugary beverages, refined grains, potatoes and desserts receive positive scores and healthy plant-foods and animal foods receive negative ones).

The cohorts were followed for over 20 years, during which participants gained on average 2 to 4.5 pounds every 4 years. Diets that were more plant-based ameliorated weight gain. But not all plant-foods and meat avoidance are the same – weight gain differed greatly among the subgroups. People who ate a more healthy plant based diet gained 1.5 pounds less. People who ate an unhealthy plant-based diet gained about 1 pound more.

The same group of researchers previously reported similar findings when studying type 2 diabetes: Overall high plant-based diets and especially healthy plant-based diets were linked with lower the risk of diabetes. Unhealthy plant-based diets, however, were actually associated with higher rates of type 2 diabetes.

What about heart disease? Again, although, overall, sticking to a more plant-based diet seems to be protective, when you look at subgroups of plant-based patterns the picture is different: Healthier plant-based diets are linked with lower heart disease risk, and unhealthy plant-based foods with higher risk.

Far from the tree

Meat manufacturers argue that meatless burgers shouldn’t be called meat; wholesome plant-based diet advocates could argue that they’re hardly a plant, either.

Calling these products plant-based takes advantage of the health halo attached to this term, and applying it to what's actually a highly processed food product, one whose plant origins are pretty distant.

Don’t get me wrong, I welcome these meat alternatives, I’m thrilled by their success; their benefit to animal welfare and the environment is reason enough to support them.

But to actually reap the benefits of a plant-based diet you’ll need to do more than replace your burger with a meatless alternative.

Dr. Ayala

Is the Mediterranean diet eco friendly?

The Mediterranean diet is respected for its health benefits. Eating Mediterranean style is associated with lower incidence of chronic disease and obesity.

It’s appreciated also for its flavor and for its practicality: Cooking Mediterranean is relatively easy, and relies on good raw ingredients simply prepared, rather than on complicated or drawn-out techniques.

Good for heath, easy on the palate and practical to prepare, but in this day and age ecological consequences are also important. Food production at the massive scale needed to supply the human population is a huge burden on the environment. Food production is a leading cause of deforestation, water pollution and loss of biodiversity. Food production uses lots of water, and generates greenhouse gases ­– about one third of global greenhouse gas emissions come from agriculture, much of it from livestock.

A new study in Public Health Nutrition evaluated the Mediterranean diet’s environmental impact.

The study involved some 20,000 Spanish participants, who reported on their food intake. The foods consumed were categorized on a sliding scale as adhering more or less to a Mediterranean diet pattern. A Mediterranean diet typically emphasizes vegetables, grains, (mostly whole/unrefined) legumes, nuts and olive oil. Fish and dairy products are eaten in moderation, as are meat and meat products; some wine is typically enjoyed. The impact of each food item on water, land and energy consumption and on greenhouse gas emission was assessed.

The researchers found that the better the adherence to the Mediterranean diet, the lower the environmental cost – natural resource use and emissions went down with Mediterranean adherence. Meat – especially beef meat – eggs, and dairy consumption had the highest detrimental impact on the environment. The results are quite impressive: Water requirements for food production for a person adhering to a Mediterranean diet is 60 percent less than what it is for someone who doesn’t, land use is 70 percent less, you need 90 percent less energy, and Mediterranean style diets produce 70 percent less greenhouse gasses.

The researchers, led by Ujué Fresán conclude:“As diet influences positively not only our health but also the environment, a nutritionist giving dietary advice may take the environmental impact of diet into account, and enhanced adherence to a MedDiet is likely to be an important target to be fostered in our society.”

Do people care about food’s sustainability and environmental impact? 

When people make their food choices they consider convenience, cost, taste, health, and availability; but do they care about sustainability and environmental impact?

“The environmental costs tend to be a tertiary discussion for most and fall well behind, ‘How do I lose weight and get off my meds?’” says Nutrition, Health & Wellness coach Scott Putnam. “People are first looking for ways to feel better and drop weight, but then get excited to learn that by eating more plant-foods, they're not only helping themselves, they are doing their part to save animal lives and the planet. It's really a Win-Win-Win situation!”

Likewise, when people first seek organic foods their primary motivation is personal avoidance of pesticides and chemicals, but choosing organic for selfish reasons evolves into an environmental commitment. “There are fruits and vegetables for which choosing organic doesn't necessarily reduce exposure to pesticides much, because the chemicals remain in the peel and do not penetrate the edible part.  So, although choosing organic may not necessarily benefit my family's potential exposure directly, I may still choose organic because I know that this choice may support organic farmers and their surrounding communities,” notes Dr. Luz Claudio, professor of environmental medicine and public health at Mount Sinai School of Medicine. 

That’s why it’s important to find an eating pattern in which health, taste, practicality and sustainability are aligned, and the Mediterranean diet is a worthy candidate.

That olive oil as the main source of fat in the Mediterranean diet also avoids another ecologic pitfall: "A personal soapbox of mine is palm oil," notes Registered Dietician Nichole Dandrea. “The palm oil industry is linked to major environmental issues such as deforestation, habitat degradation, climate change, animal cruelty and indigenous peoples rights abuses. The World Wildlife Fund states that rainforest areas equivalent to 300 football fields are cleared every hour to make way for the palm oil industry.” She encourages avoiding palm oil unless it's Certified Sustainable Palm Oil (CSPO).

We can all take steps towards greater sustainability by eating more plants and less meat (this is the single most impactful decision), eating less processed foods, choosing organic when possible, preferring produce that's locally grown and in season, and avoiding waste.

Even the smallest steps count in a world with more than seven and a half billion people making food choices.

Dr. Ayala

Some good news about organic food

Fall is here, the time to celebrate the harvest.

And a good occasion to look at what’s new in organic food. Here are a few fresh reasons to be optimistic.

Does organic food promote health?

The European Parliament commissioned a group of experts to review the health advantages of organic food and farming, and the report was published earlier this year.

One of the main takeaways concerns pesticides.

Organic farming restricts the use of pesticides and relies on prevention for plant protection. Eating organic foods lowers the risk of exposure to pesticides and herbicides. Are the low levels of pesticides in conventional foods harmful? Several studies reviewed in this report have shown that exposure to these chemicals during pregnancy was associated with harm to kids’ intelligence quotient (IQ) and development. The report therefore concludes that organic food is especially beneficial for pregnant and breastfeeding women.

Another finding is that kids on a biodynamic diet had lower rates of allergic complaints. It is hard to definitely attribute the better health of these kids to organic food, as there might be other healthy habits contributing to their healthier disposition.

And then there are the antibiotics. Organic practices restrict those, and result in agriculture, land and water, that’s lower in both antibiotics and heavy metals, such as cadmium. Overuse of antibiotics leads to antibiotic resistance; organic practices mitigate this public health problem.

The report concludes that there are proven benefits to organic practices, and suggests several policies that could help spread the use of organic farming and foods.

There was lots of media hype around studies that looked at nutrient levels in organic vs. conventional produce. Regarding nutrients, the jury’s still out, and the difference might not be significant enough to matter much. Some studies showed higher antioxidant levels in organics, other showed lower levels of iodine in them.

Regardless, the important issues listed above – pesticides, antibiotics and heavy metals – are reason enough in my opinion to conclude that organic food is healthier for its consumers. And it’s definitely better for the environment, for farmers, and for all other living creatures downstream.

Organic farming is growing in the US

A recent report from the US Department of Agriculture (USDA) showed that sales of organic produce were up 23 percent in 2016.

The number of certified organic farms in the country increased 11 percent last year, and the number of certified acres increased 15 percent, to 5 million.

California leads in organic food sales, but my home state of Pennsylvania is in second place!

Young people believe in organic

Organic food adoption is up overall, rising about 10 percent each year, but its popularity is especially prominent among young adults. In a recent Pew research poll 61 percent of under 30-year-olds said that organic is better than conventionally grown food; it was almost that high (57 percent) for people aged 30-49 years.

Among adults younger than 50 years, 71 percent bought organic foods at least once in the past month, and about 40 percent of all US age groups say that most or some of what they eat is organic. 

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All these are reasons to cheer, but a note of caution: Organic food is still just a tiny sliver of overall farming and produce.

But by supporting organic and clean eating with our purchases we, each of us, are backing the movement. We’re voting for the health of our planet with our wallets.

Dr. Ayala

Healthy food trends to take advantage of in 2017

Eating your veggies is suddenly hip.

You might accuse me of being biased – and for full disclosure, yes, I’ve always been a huge veggie and plant-based food fan and proponent – but look around you and see the signs.

In restaurants, veggies are taking center plate; menus are listing more plant-based offerings as many Americans declare they are trying to eat less meat. Pinterest reports a 336 percent rise in the search for veggies in comfort foods.

And this trend will only expand next year.

The market research agency, Mintel, recently announced 2017's food trends, predicting further expansion of vegetarian, vegan and other plant-focused interest.

The Baum and Whitman consultancy's trend predictions follow the same lines:

“Vegetables in 2017 will extend their domination of the dinner plate, shoving animal protein to the edges ... or off the plate altogether… It is no secret that Americans are eating less meat (26% of consumers said so last year) ... that vegetarian/flexitarian diets going mainstream ... and that vegans increasingly are gaining respect.”

Trends shape health

These current trends are sure to please health and sustainability advocates – and grandmas -- who have been drumming the fruit and veggie advice into everyone’s head forever. Plant-centered diets are not only healthful and nutritionally adequate, they have also been shown to prevent and treat many diseases, and people practicing them are among the longest lived and most vibrant people on this planet.

Yet nothing seemed to move for the longest time. And that’s understandable: habits are very hard to change.

It seems that a message needs to come from many different directions, in several modalities and forms, in order to affect action, and in that respect trends help greatly. Just look at what the cool factor – or lack of it – did to cigarettes, spinning, yoga and running.

Greens are in, and 2017 is the perfect time to jump on this trend and adopt healthier habits.

To a healthy 2017

New year resolutions are often broken by the end of January, but a trend, by definition, is something that people are ‘dragged’ into without much resistance, or with minimal effort.

If you’ve been trying to eat a little bit better, chances are, this will be a good year to clinch a few good habits.

A few tips:

• As you continue to hear the “eat more plants” message from health experts, notice how attractive this option is becoming, by looking at recipes, menus and Instagram posts.

• Make plant-centered options convenient, tasty and attractive; this will make this choice easier for you and for your family. Place that pretty, ready-to-eat fruit bowl a little closer and it will be as convenient as a bag of chips.

• Remember: Making small steps in the right direction helps a lot, and this isn’t an all or nothing game. By eating more fruits and veggies you'll be benefiting your health, and displacing less healthy items – such as added sugar, highly processed food and processed meat -- from your dish and cup.

Wishing you happy and healthy holidays, and a peaceful 2017.

Dr. Ayala

Three thoughts on watermelon

One of the best things to enjoy on a warm summer day is a cold watermelon.  Sweet, hydrating, crisp, refreshing, red (what a beautiful color!) and nutritious -- what could be better? Here are a few things that can make your watermelon experience more complete.

1. My 'no guarantee' tips for picking a winner

 

Have you seen those square watermelons? Well, these tips won't work for those space-saving fruit, but for your ordinary rounded watermelon these come in handy:

Tapping: Tap the watermelon with the pads of your fingers. A winning watermelon will typically have a slightly hollow sound, like the sound you get when tapping your head rather than tapping your chest.

The all important yellow spot: At the bottom of the watermelon -- where it rested on the ground -- you want to find a yellow or cream-colored spot. If the spot is still white, the watermelon isn’t ripe. Some say this is the most important clue to watermelon goodness.

Firmness: Press your fingers and thumbs into the watermelon’s skin. A good one should be hard all around with no soft spots.

Weight for size: A good watermelon feels heavy for its size.

Good luck!

2. A great recipe for a not-so-great watermelon

Good news: a not-so-sweet watermelon makes a wonderful and easy-to-prepare cold soup. (The cucumber in the recipe masks the cucumberness of the not-so-great watermelon.) It looks like a gazpacho, but is even more refreshing.

Watermelon and mint cold soup

Ingredients

6 cups seedless watermelon, diced
1/3 cup finely chopped fresh mint
1 cup cucumber, peeled and finely diced
1 small jalapeño pepper, seeds removed, minced
1 red onion, diced
1/2 cup young celery stalks, diced
2 tablespoons fresh lime juice or to taste
2 tablespoons balsamic or red wine vinegar
salt and fresh ground pepper to taste 

Preparation

Puree the watermelon in a food processor, using the “pulse” setting; pulse several times until the watermelon is still chunky and not too smooth.

Transfer the puree to large bowl. Add the remaining ingredients. Refrigerate until cold (at least an hour).

Garnish with a few leaves of fresh mint and serve.

3. Why's a watermelon good for you?

First and most important – it’s a fruit and it tastes good. Its color brightens up the table.

Watermelon is a low calorie nutritious treat: a one-cup serving of watermelon has only about 50 calories.

Watermelon is 92 percent water so it’s very good for hydration.

It’s an excellent source of vitamins C and A. It’s also a good source of vitamins B6 and B1, and minerals such as potassium and magnesium. Red watermelon (yes, there’s a yellow-orange type too!) is also a good source of lycopene (a carotenoid antioxidant). In fact, watermelons are a richer source of this beneficial antioxidant than tomatoes.

In a recent New Your Times blog post, Roni Caryn Rabin interviewed experts on lycopene and watermelon health:

"You can get lycopene from tomatoes, particularly cooked and stewed tomatoes, but “on a fresh basis, you can’t do better than watermelon,” said Penelope Perkins-Veazie, a professor at North Carolina State University in Raleigh who has studied lycopene and is an unpaid science adviser to the National Watermelon Promotion Board. Red watermelon has more lycopene than other watermelon varieties, and “seedless watermelon tends to have more,” she said."

While we mostly eat the flesh of the watermelon, all parts are actually good to eat. The rinds can be stir-fried, stewed or pickled. Watermelon seeds are rich in fat and protein, and can be eaten as a snack (roasted), or made into an oilseed.

Enjoy!

Dr. Ayala

Can hummus help you lose weight?

The United Nations designated 2016 the International Year of Pulses. The goal is to increase awareness, demand and intake of this plant food, as “in many countries, consumer, food industry members, and governments have little knowledge of pulses, their attributes, or their ability to contribute to the solution of many food related issues facing the world today.”

The global epidemic of obesity is a major health threat. Could pulses offer a remedy for this important nutrition issue? Pulses -- edible seeds that grow in pods, including beans, lentils, chickpeas and dried peas -- have lots of fiber and protein, a low glycemic index, and one could imagine that these traits are beneficial to weight loss. A new study, led by Shana Kim and appearing in the American Journal of Clinical Nutrition set out to see if in practice, people who eat pulses actually lose weight.

The researchers found 21 randomized clinical trials in which 940 participants were assigned a diet that either included pulses or served as a control – with no pulses. In all cases the pulse diet and the control were matched in caloric intake, and the diets lasted a median of 6 weeks.

Those eating one serving of pulses a day lost 0.34 kg (¾ of a pound) when compared to the people on the no-pulses diets – this on a diet that was identical in calories. Even in trials that were designed for weight maintenance, and in which the participants weren’t calorie restricted, the pulse eaters lost weight. Although it’s not a lot of weight loss, one can imagine that if this trend is sustained over a year that could mean 3kg, or about 6½ pounds lost in a year through a no-deprivation, easy step that involves substituting some of the grain and starches in the diet with beans, lentils and hummus. 

Is a calorie not a calorie?

What could explain pulses’ weight loss effect? Is a calorie not a calorie? The authors offer a few possible explanations. Pulses may cause greater satiety. In fact, they quote a study that shows that there is a 31 percent increase in reported satiety after meals that contain pulses. This might lead to better adherence to a diet regimen.

The other mechanism they offer is that not all foods are absorbed the same. Foods that are high in fiber might reduce the absorption of fat in the diet, and the tough cell walls of some pulses might also not allow absorption of all their starches. If this is the case the quoted caloric content of the pulses doesn’t reflect what the body gets out of them, as some of their energy isn’t utilized because the digestive enzymes don’t break them down completely.

There are many reasons to add pulses to your meals. They are tasty, versatile, inexpensive, and sustainable. If they can help with weight maintenance this would be the cherry on top.

Dr. Ayala

Looking for recipes that incorporate pulses? Here are a few of my favorites:

Red lentil and spinach soup

Tofu, kale and black bean burritos 

Edamame dumplings in vegetable and white truffle broth

Homemade hummus

Downton Abbey finale has a lesson in nutrition

I’m going to miss Downton Abbey. Escaping into the lives of the Crawleys was a wonderful Sunday night treat – that always left me grateful to be living in our era, especially as a woman.

For those of us nostalgic for old times, and especially those who claim nutrition science is useless, there was a small lesson to be learnt from the drama-packed finale.

(If you haven’t been following the series it really doesn’t matter; read on. Spoiler alert for those who haven't watched the chapter yet, although I'm not giving away much.)

Lord Merton, Isobel’s onetime fiancé discloses that he has a terrible diagnosis. He was feeling weak, and visited the best doctors in London, who ran all the tests and diagnosed anemia. Isobel’s worried face lightens up hearing this, but Lord Merton quickly brings her hopes down. At this point I thought he was going to say he has leukemia, but what he has is pernicious anemia – and Isobel realizes his end is near.

Pernicious means dangerous, destructive, deadly.

So what’s Lord Merton malignant condition? Are Isobel’s gloomy tears justified?

Pernicious anemia was described by English researchers in the mid nineteenth century. Patients had anemia with all its symptoms (fatigue, pallor, rapid heart beat), and also mental slowness, memory loss, numbness and tingling of hands and feet, walking difficulties and mild dementia. In the lab, a blood smear would show megaloblasts: abnormally large immature blood cells. It was an invariably fatal, rapidly progressive disease.

Nowadays, pernicious anemia’s death sentence is overturned within 1-2 days – with one injection.

What causes this mystery fatal illness?

Pernicious anemia is B12 deficiency. This vitamin was finally discovered and isolated in 1948 – many decades after the disease was first described and 23 years after the time described in this Downton Abbey chapter. B12 deficiency is usually a result of inability to absorb the vitamin, but can also develop in cases where intake of the vitamin is very low – such as in vegans who don’t take B12 supplements and their exclusively breast-fed infants. Only animal-origin foods have B12: dairy, eggs fish and meat and shellfish are all good sources.

There might be pieces of the past we wish we could have held on to, but with all the criticism we rightfully have of modern medicine let’s be thankful for all the suffering it has helped us avoid. It’s because we now know so much more about nutrition that the classic nutritional diseases (such as scurvy, beriberi, pellagra and rickets) are rare and easily treated.

People often say nutrition science is confused, that advice changes every other week. Well, nutrition science is a young science, and like all science it is moving towards the discovery of truth – sometimes taking an unfortunate detour on a path that leads nowhere before correcting course. The main problem is the abuse and hype nutrition science suffers by the hands of weight-loss and food marketers. Diet and exercise programs sometimes latch onto flimsy evidence, twisting and exaggerating findings, and creating an enormous amount of hype – to their gain and the general public’s confusion.

Science is complex and slow moving. Nutrition science it especially difficult, because it deals with people eating – at their own will – diverse foods throughout a lifetime. We are moving towards answers and consensus at a much faster rate than we did in Downton’s time, and with some patience and perspective – and less distractions – we will know much more.

I’m going to miss Downton Abbey, and its reminders of how far we’ve come.

Dr. Ayala

Black lentil, sweet potato and carrot soup

I love green lentils, and use red ones a lot too, but once you try the black variety I think you'll never look back. Black lentils soften quite quickly, but remain intact after cooking, dotting this satisfying, nutritious soup with dark contrasting-colored bits of delicious beauty.

Ingredients:

• 2 sweet onions
• 2 tablespoons olive oil
• 5 carrots, cut into large cubes
• 2-3 sweet potatoes, cut into large cubes
• 1 tablespoon paprika
• dash of cayenne pepper
• 1/2 teaspoon tumeric
• Salt and pepper to taste
• 6 cups water
• 2 tablespoons miso paste (I prefer the white mellow)
• 1 cup washed black lentils
• 2 cups spinach leaves, chopped
• ½ cup dill, finely chopped
• Garnish: fresh dill or cilantro, chopped

Preparation:

• In a large pot, on medium-high heat, sauté the onions in olive oil until soft and golden. Add the carrots, sweet potatoes, paprika, cayenne pepper, turmeric, salt and pepper, and sauté for about 15 minutes, until sweet potatoes are quite soft. Add a little water if the the pot seems too dry
• Add the water, bring to a boil, simmer until the vegetables are soft but still tender
• Remove from heat, add the miso paste to the pot, and with an immersion blender process until smooth
• Wash the lentils in a sieve with plenty of cold water. Add to the pot, bring to a boil, lower to a simmer, and cook about 20-30 minutes, until the lentils are soft, turn off heat
• Add the spinach and the dill (heat's already off, but the soup is still very hot, so spinach will wilt nicely)
• Taste and correct seasoning.
• Garnish with a spinkle of herbs and serve with a nice loaf of bread. 

Enjoy!

Dr. Ayala