This may seem like a silly question, since all food provides calories, and you can potentially eat too much of anything and fatten up.
On the other hand certain foods and lifestyles do seem to be associated with overeating and weight gain.
And since weight loss is ever so difficult and once achieved even harder to maintain, figuring out which eating pattern is more likely to prevent weight gain over the years can offer a logical preventive plan for addressing our obesity crisis.
Which foods are linked with weight gain? To answer this question, a new study in the New England Journal of Medicine tracked changes in the eating habits of more than 120,000 professionals -- who all started out as non-obese -- while following their weight for about 20 years. The study’s findings shed some light on weight gain over time.
Weight gain is slow and insidious
For most people, weight gain isn’t a dramatic event. Weight, much like aging, changes so slowly that you don’t notice it at all; until one day enough change has taken place that your image in a photo puts you into a state of shock.
In this study the average weight gain was about 3.5 pounds every 4 years – just under 1 pound-a-year – which really isn’t that much, yet over the 20 years of follow-up participants gained an average of 17 pounds.
French fries and sugary drinks linked to weight gain; Fruits, veggies, nuts and yogurt linked to weight loss
Certain foods were independently related to weight gain. The foods showing the largest effect were:
- Potato chips and French fries
- Sugar-sweetened beverages (soda and other sugary drinks)
- Unprocessed and processed meats
Other foods were associated with weight loss:
- Vegetables
- Whole grains
- Fruit
- Nuts
- Yogurt
Is a calorie not a calorie?
Is there something special about fried potatoes and sugary drinks that makes them especially fattening? Isn’t it surprising that adding nuts to your diet – nuts are some of the most caloric-dense foods on the planet – was associated with less weight gain?
The authors, led by Dariush Mozaffarian, from the Harvard School of Public Health, offer this explanation: Dietary quality (the types of foods and beverages consumed) influences dietary quantity. Increasing the consumption of veggies, fruits and nuts probably reduced the intake of other, more caloric-dense foods, overall decreasing caloric intake. Whole, unprocessed foods have more bulk, are digested slowly, and probably cause more satiety. Drinks, other studies have shown, are less satiating than solid foods. This study, too, showed that all caloric drinks except milk were associated with weight gain.
There’s another possible explanation: People who care about healthy weight tend to also care about healthy eating, therefore both weight maintenance and healthy eating just happen to go together, because people who are committed to not gain weight also eat healthy. Eating fruits, vegetables and nuts is also linked to being physically active, but definitely doesn’t cause it. Good habits tend to cluster, and it’s very difficult to prove cause and effect with these kinds of things. (It took quite a lot of research to figure out that while healthy people tend to take vitamins, taking vitamin supplements doesn’t make you any healthier.)
Nevertheless, I have no doubt that our obesity crisis is a result of overeating. It’s a fact that most of the extra calories we’ve added over the past 30 years come from highly processed foods, refined carbs and starches and sugary drinks. Is there something unique about these foods that makes overeating them more likely? I think this study provides some support to the notion that the answer is yes! There’s also plenty of evidence that these processed foods are bad for our health, and their overconsumption is linked with chronic disease.
Dietary quality probably does influence dietary quantity; it’s just easier to eat fewer calories when you’re eating well.
Dr. Ayala
Reposted as part of Food Renegate's Fight Back Fridays -- join the food fight!