FAD diets and Leptin:
FAD diets promise quick weight loss, but they involve unhealthy and unbalanced eating plans. When proper food is brought back into someone’s diet, they gain weight rapidly. Leptin is a hormone that is important for its role in regulating food intake and energy expenditure. This hormone is produced by fat cells that signal satiety. Leptin is also shown to control the insulin-glucose axis as well as insulin responses. Since it was discovered, leptin has been used as a therapy for obesity and diabetes. Leptin, however, has been shown to be the reason why dieting does not work. With FAD diets, leptin receptors can become resistant the same way people with diabetes experience insulin resistance. The problem with these quick diets and fast weight loss is that the body becomes depleted of leptin, which makes individuals hungry all the time.
Keto diet and Leptin:
The Keto diet is one that causes the body to release ketones into the bloodstream. Most cells prefer to use blood sugar for energy, which comes from carbohydrates, however once on a ketogenic diet, there are very few carbohydrates for the body to utilize. In the absence of carbohydrates and circulating blood sugar from food, the body starts to break down stored fat into molecules called ketone bodies. Once the body has reached the stage of ketosis, most cells in the body will use ketones for energy until carbohydrates are consumed again. During a keto diet, the ability of insulin to regulate blood sugar levels is changed due to the content of macronutrients. During a high-fat diet, individuals can experience insulin resistance and an inability to maintain good glucose levels. While on a keto diet however, it has been seen to help symptoms of diabetes. Some Studies show that the ketogenic diet can increase leptin and decrease insulin, which is unusual because leptin and insulin levels normally change together, with both either increasing or decreasing. During conditions associated with weight loss, like fasting, there was a decrease in both leptin and insulin. During conditions associated with weight gain, like overeating, caused both Leptin and insulin resistance to increase. This shows that the ketogenic diet plays a unique role on the metabolic state and the opposite changes in levels of leptin and insulin also lead to a unique neurohormonal state
Sources:
Alex. (2021, October 31). The problem with fad diets. Ryan and Alex Duo Life. Retrieved November 24, 2021, from https://www.ryanandalex.com/problem-fad-diets/.
Amitani, M., Asakawa, A., Amitani, H., & Inui, A. (1AD, January 1). The role of leptin in the control of insulin-glucose axis. Frontiers. Retrieved November 24, 2021, from https://www.frontiersin.org/articles/10.3389/fnins.2013.00051/full.
Kinzig, K. P., Honors, M. A., & Hargrave, S. L. (2010). Insulin sensitivity and glucose tolerance are altered by maintenance on a ketogenic diet. Endocrinology, 151(7), 3105–3114. https://doi.org/10.1210/en.2010-0175
