A study published in the American Journal of Physiology: Endocrinology and Metabolism investigated the effects of overeating for short periods of time versus long periods of time.
Overeating is a common habit that can interfere with the body’s metabolic processes and lead to issues such as obesity and diabetes. Human studies have been done to better understand the metabolic changes involved in overeating, but oftentimes the diet consumed is altered to be higher in fat than the typical diet, a factor that may influence the results. To account for this, researchers in a recent study examined the metabolic changes that occur with short-term and long-term overeating in people who still maintained their typical dietary habits.
For the study, researchers used eight healthy men. Any participants who were obese, smoked, exercised frequently or had a family history of diabetes were excluded from the study. All participants took part in two trials: one modeling overeating for five days and one modeling overeating for 28 days. Prior to beginning the study, researchers took blood samples to analyze hormones and metabolites, and measured body composition to analyze any changes in fat mass. To simulate overeating, the participants consumed their normal diets, composed of 55% carbohydrates, 15% proteins and 30% fats, but were given snacks to increase their intake by approximately 1000 calories. During each trial blood samples were taken regularly after eating, and participants recorded their consumption in food diaries.
Short-term overeating does not result in significant weight gain
On average the participants consumed a calorie surplus of 46%. Overeating both short term and long term resulted in increased fat around internal organs, but only long-term overeating resulted in higher fat and body masses. With long-term overeating, participants had higher blood sugar levels following a meal, but the production and removal rates of glucose, as well as fasting blood sugar levels remained the same.
Based on the results, researchers believe that during short-term overeating, the body adapts to remove glucose specifically. It is important to note, that although participants were eating in excess, they were still consuming their typical core diets. As the study included only lean men, exploring the effects of overeating on different demographics would serve useful to provide a bigger picture of the effects on the general population.
Written by Monica Naatey-Ahumah, BSc
Morrison, D.J., Kowalski, G.M., Bruce, C.R., and Wadley, G.D. (2019). Modest changes to
glycemic regulation are sufficient to maintain glucose fluxes in healthy young men
following overfeeding with a habitual macronutrient composition. American Journal of Physiology: Endocrinology and Metabolism, 316(6).