Two hormones that play a critical role in optimizing your metabolism for weight control are insulin and leptin. The importance of insulin in health and disease is better known. Our bodies release insulin right before and during eating. Insulin then tells our bodies to start taking glucose out of the blood, thus lowering our blood glucose levels. Without insulin, we would all go into hyperglycemic shock and die after eating food! Insulin directs the cells to either burn or store fat or sugar and whether to utilize that energy for maintenance and repair or reproduction.
Excess Insulin and Fat Storage
Here’s a very important principle to understand – your body simply won’t break down and use your fat reserves with excess insulin around. Meaning, those who are insulin resistant and have elevated insulin levels throughout the day, won’t be able to release fat for fuel – no matter how much they exercise. However, controlling insulin by limiting your carbohydrate intake is the most effective way to open up the fat gates and give the body access to the fuel stored behind them. This is so important, it bears repeating – insulin locks fat in the fat cell; excessive carbohydrate consumption causes elevated insulin levels. In addition to the obvious role of insulin in diabetes, it also plays a significant role in hypertension, cardiovascular disease, and cancer.
Newer research suggests that leptin may be even more important than insulin because glucose and insulin levels may be heavily influenced by leptin. Leptin is a hormone that plays a crucial role in appetite and weight control. Its two major functions are first, to cross the blood-brain barrier, bind to receptors in the appetite center in the brain, and regulate brain cells that tell you how much to eat. Second, it increases sympathetic nervous system activity, which stimulates fatty tissue to burn energy. In short, leptin is the way that your fat stores speak to your brain to let your brain know how much energy is available and what to do with it.
Insulin and Leptin Resistance
As previously stated, elevated blood glucose levels cause spikes in insulin that can eventually cause your cells to become insulin resistant, leading to continued elevated levels of insulin and diabetes. It is believed the same happens with leptin. As sugar gets metabolized in fat cells, fat releases surges in leptin, and these surges cause leptin resistance. Chronically elevated leptin levels are associated with overeating and obesity.
In addition, excess levels of insulin and leptin circulating in your body are very inflammatory. Both insulin and leptin resistance are associated with obesity, and impairment of their ability to transfer the information to receptors is the true foundational core of most all chronic degenerative diseases (heart disease, diabetes, osteoporosis, autoimmune diseases, reproductive disorders, and possibly even the rate of aging). In order to re-establish proper leptin and insulin signaling, one must prevent those spikes via diet and supplements. The bottom line is – a healthy diet that focuses on the right amount of protein, fat, and carbohydrates (macronutrients), thereby preventing blood sugar spikes, will enhance insulin and leptin sensitivity. Once insulin and leptin signaling is restored, your brain can now hear the message that you have too much fat and start burning a percentage off.