Impact of a Low-Fat, Plant-Based Diet on Weight, Metabolism, and Insulin Sensitivity

This article summarizes the research study "The effects of a low-fat, plant-based dietary intervention on body weight, metabolism, and insulin sensitivity" published in 2005 by Neal D. Barnard, Anthony R. Scialli, Gabrielle Turner-McGrievy, Amy J. Lanou, and Jolie Glass.

The study aimed to compare a low-fat vegan diet to a standard cholesterol lowering diet in overweight postmenopausal women. The goal was to analyze the effects on weight, body composition, metabolism, and insulin sensitivity.

- 64 overweight postmenopausal women were split evenly into a vegan diet group and control diet group based on National Cholesterol Education Program guidelines

- Outcomes measured at baseline and after 14 weeks included:

- Body weight and composition

- Resting metabolic rate

- Insulin sensitivity

- Exercise was kept constant

- The vegan diet group lost significantly more weight – averaging 5.8 kg versus 3.8 kg in the control group

- The vegan diet also improved insulin sensitivity scores, but between-group difference was not statistically significant

- Changes in resting metabolism and thermic effect of food correlated with weight loss

Over just 14 weeks, the low-fat vegan diet led to greater weight loss and improved metabolic factors compared to a standard cholesterol lowering diet in overweight postmenopausal women, despite allowing unlimited portion sizes.

Barnard, N. D., Scialli, A. R., Turner-McGrievy, G., Lanou, A. J., & Glass, J. (2005). "The effects of a low-fat, plant-based dietary intervention on body weight, metabolism, and insulin sensitivity." The American Journal of Medicine, 118(9), 991-997. Available at: https://www.amjmed.com/article/S0002-9343(05)00279-2/fulltext