According to a study led by Harvard T.H. Chan School of Public Health, low-carbohydrate diets, composed of plant-based proteins and fats with healthy carbohydrates, like whole grains, were associated with long-term weight gain than low-carbohydrate diets, with mostly animal proteins and fats with unhealthy carbohydrates, such as refined starches.
Lead author Binkai Liu, research assistant in the Department of Nutrition, said their study goes beyond the simple questions of “To carb or not to carb?” Instead, it dissects how low-carbohydrate diets provide a glimpse at how compositions can affect health in the long run.
Despite the numerous studies highlighting the benefits of cutting carbohydrates for short-term weight loss, few focus on low-carb diets’ effect on long-term weight maintenance and the role of food group quality.
The researchers analyzed the diets and weights of 123,332 healthy adults from 1986 to 2018 using data from previous credible studies. Each participant provided self-reports of their diets and weights every four years, while researchers scored the diets based on how well they adhered to five categories of a low-carb diet.
Results showed that diets with plant-based proteins, fats, and healthy carbohydrates were significantly associated with slower, long-term weight gain. These findings were more pronounced among participants below 55, overweight or obese, and less physically active.
Senior author and associate professor in the Department of Nutrition Qi Sun said that the primary takeaway is not all low-carbohydrate diets are equal in managing weight in the long run. Moreover, their findings can change the way the public sees popular low-carbohydrate diets to develop public health initiatives to promote dietary patterns that promote healthy food like whole grains, fruits, vegetables, and low-fat dairy products.