We’ve long heard that there are no “bad” foods, but researchers at Harvard Medical School might not agree.
For 20 years, they followed the diet and exercise habits of over 120,000 individuals, and they found that eating certain foods led to greater weight gain than other foods. The results were just published in The New England Journal of Medicine.
On average, participants gained 3.35 lbs. over each 4-year period—almost a pound a year. So over 20 years, the participants—mostly nurses and physicians—were packing on over 16 pounds, but that’s the average. Some gained more and some gained much less.
The Worst Foods
As the researchers analyzed the data, they discovered that the kinds of foods participants ate made a big difference. Here are the foods that you should avoid or at least save for special occasions.
1. French fries – Over 4 years, these added 3.35 lbs to participants’ hips and thighs (Okay, the researchers weren’t that specific, but you know that’s where the fat cells like to congregate and party.)
2. Potato chips – More with the fried potatoes. These weren’t as bad as the fries, but still added 1.7 lbs.
3. Sugar-sweetened drinks – Sodas, shakes and slurpees go down quick and added a pound of weight.
4. Processed meats – Fancy talk for hot dogs, sausages and chicken nuggets and these foods added a pound.
5. Red meat – Also added about a pound over each four-year time period.
The Best Foods
The happy news? With some foods, the more servings participants ate, the less they weighed.
1. Yogurt – Associated with almost a pound weight loss. Researchers aren’t sure if it’s the action of the good bacteria in the yogurt or something else, but results were consistent.
2. Nuts – Yes, they have a lot of calories, but people who ate nuts were down about half-a-pound compared to those who didn’t eat nuts (and nuts have the good kind of fat).
3. Fruits – Not a huge surprise, but good to know that eating the yummy fruits that are in season will also keeping you thin.
4. Veggies – Again, not a shocker, but a little surprising that veggies had a lower effect than yogurt in this study.
5. Whole grains – Switching from refined grains to whole grains is one of those changes that looks small, but adds up over time.
Study published in The New England Journal of Medicine, June 23, 2011, “Changes in Diet and Lifestyle and Long- Term Weight Gain in Women and Men”
Study authors: Dariush Mozaffarian, M.D., Dr.P.H.; Tao Hao, M.P.H.; Eric B. Rimm, Sc.D.; Walter C. Willett, M.D., Dr.P.H.; and Frank B. Hu, M.D., Ph.D.