Leucine is a branched-chain amino acid that serves as a building block for new proteins, and is a key signalling chemical for protein synthesis and blood sugar regulation. A study in Nutrition Metabolism, conducted by Columbia University in New York City, found that leucine improved blood sugar control in obese and diabetic mice. The mice were given leucine supplements in their drinking water for 8 months. Leucine stimulates insulin release by the pancreas and promotes the production of the amino acid glutamine, which is important for immune system health. Long-term supplementation of leucine improves the efficiency of insulin metabolism in people with type II diabetes.
Low-carbohydrate weight-loss diets increase the production of ketones formed form the incomplete breakdown of fats. Ketogenic diets cause rapid short-term weight loss but are no more effective than other low-calorie diets for long term weight loss or weight maintenance. A university study published in Endocrinology, used rats and concluded that ketogenic diets have long-lasting negative effects on blood sugar regulation. Rats that were fed low-carbohydrate diets then switched to a normal diet showed impaired insulin sensitivity and poor blood sugar control. Yo-yo dieting (bouncing between ketogenic and normal diets) may have long-term negative effects on blood sugar regulation.