Last week, an article* in the New England Journal of Medicine caused quite the hubbub in nutrition circles. The article, “Changes in Diet and Lifestyle and Long-Term Weight Gain in Women and Men” used data on 120,877 people from several longitudinal studies, all of whom were non-obese and free of chronic disease at baseline. The study examined the effects of diet (including specific foods), physical activity, television watching, alcohol use, sleep duration, and smoking on weight gain over a period of 20 years.

The average weight gain during each 4-year period was 3.35 lb., or an average of 16.8 lbs over 20 years.  Not surprisingly, increases in alcohol use and time spent watching television were associated with weight gain, as was sleeping less than 6 hours or more than 8 hours per night. Increases in physical activity were associated with less weight gain.

Several news outlets jumped on the findings that several specific foods were linked with more weight gain over the study period, including: potatoes, processed meats, unprocessed red meats, refined grains, whole fat dairy, and sugar-sweetened beverages. Foods associated with lower weight gain included fruits, vegetables, whole grains, and low-fat dairy. This finding shouldn’t come as a shock to anyone – people who are eating more servings of fruits, vegetables, and whole grains are likely to have an overall healthier diet (and lifestyle) than those consuming french fries and soda.

Average change in weight (lbs) associated with consuming 1 additional serving of a specific food over 4-yr. period

The take-home point is this:

Overall, our analysis showed divergent relationships between specific foods or beverages and long-term weight gain, suggesting that dietary quality (the types of foods and beverages consumed) influences dietary quantity (total calories).

While the results of this study aren’t surprising, it is important because it breaks down long-term weight gain in non-obese people, which effects most people as they age, even if they don’t realize it. An average increase in caloric intake of as little as 50-100 extra calories per day can lead to weight gain of 1lb per year (an extra 3,500 calories corresponds to a weight gain of 1 pound). That’s just 1 extra average-sized cookie or 12-ounce soda every day! Gaining 1-2 pounds each year may not seem like a big deal now, but it increases one’s risk for chronic disease and cancer over time. This study provides data to back up what nutritionists have been saying for years – the overall quality of your diet, not just counting calories, is what really matters.


*if you would like a copy of the article (PDF) and do not have access to it, please contact me

**image from The Atlantic