Cookies on Nutrition and Food Sciences

Like most websites we use cookies. This is to ensure that we give you the best experience possible.


Continuing to use  means you agree to our use of cookies. If you would like to, you can learn more about the cookies we use.

Nutrition and Food Sciences

Nutrition and food science information across the food chain supporting academic and industrial research

>>> Sign up  to receive our Human Sciences e-newsletter, book alerts, and offers <<<

News Article

Diet composition can affect long term weight gain

Changes in protein source and in glycemic load synergistically influence bodyweight

Making small, consistent changes to the types of protein- and carbohydrate-rich foods we eat may have a big impact on long-term weight gain, according to a study led by researchers at the Friedman School of Nutrition Science & Policy at Tufts University in the USA. They found that people who increased intake of red meat or increased the glycemic load (GL) of their diet gained more weight over 4 years than those who increased their intake of nuts, dairy foods, and legumes or decreased their GL. The study suggests there is more to weight gain than calorie intake, diet composition matters too. The results were published in the The American Journal of Clinical Nutrition.

This study by Jessica Smith and colleagues analysed data from 120,000 men and women from three long-term studies of U.S. health professionals. The diets and weights of the participants were measured at base line and at intervals over 16 years. The researchers measured the association between 4 year changes in diet and changes in body weight over the same period.

Smith and colleagues first looked at the relationship between changes in protein foods and weight gain during every four-years of follow-up. Previous work suggests that higher protein levels generally in the diet might improve satiety and help weight loss. There is also some evidence that consumption of fattier meats may contribute to weight gain.

Smith and colleagues found that:

• Increasing intakes of red meat and processed meat were most strongly associated with weight gain.
• Increasing intakes of yogurt, seafood, skinless chicken, and nuts were most strongly associated with weight loss.
• Increasing other dairy products, including full-fat cheese, whole milk, and low-fat milk, did not significantly relate to either weight gain or weight loss.

“The fat content of dairy products did not seem to be important for weight gain,” Smith said. “In fact, when people consumed more low-fat dairy products, they actually increased their consumption of carbs, which may promote weight gain. This suggests that people compensate, over years, for the lower calories in low-fat dairy by increasing their carb intake.”

Next, the authors noted several synergistic relationships between changes in protein-rich foods and changes in GL of the diet. Glycemic load is an estimate of the impact of a food on blood glucose. A high GL food raises blood glucose more than a low GL food. Although there are exceptions, high GL diets typically contain refined carbohydrates.

The authors found that increasing servings of foods linked to weight gain, and at the same time increasing GL by eating more refined carbohydrates, strengthened the foods’ association with weight gain. But decreasing GL by eating, for example, red meat with vegetables, mitigated some of that weight gain.

For fish, nuts, and other foods associated with weight loss, decreasing GL enhanced their weight loss effect, while increasing GL decreased their weight loss effect. Notably, although other foods like eggs and cheese were not linked to weight change on average, when servings of these foods were increased in combination with increased GL, they were linked to weight gain. On the other hand, when servings of eggs and cheese were increased in combination with decreased GL, the participants actually lost weight.

“Our study adds to growing new research that counting calories is not the most effective strategy for long-term weight management and prevention,” said senior author Dariush Mozaffarian. “Some foods help prevent weight gain, others make it worse. Most interestingly, the combination of foods seems to make a big difference.”


Smith JD, Hou T, Ludwig DS, Rimm EB, Willett W, Hu FB and Mozaffarian D. “Changes in intake of protein foods, carbohydrate amount and quality, and long-term weight change: results from 3 prospective cohorts.” The American Journal of Clinical Nutrition 2015;101:1-9. Published online ahead of print April 8, 2015.


Article details

  • Author(s)
  • I. Hoskins
  • Date
  • 10 April 2015
  • Subject(s)
  • Nutrition & health