Are you familiar with these denominations- Insulin, hormones, receptors etc etc….
Don’t worry we will not go in to deep discussion of hormones but to understand how body regulates our set point these are inevitable.
As we all know that obesity is not caused by excess calories but instead by a body set weight that is too high because of a hormonal imbalance in the body. Hormones are chemical messengers that regulate many body systems and processes such as appetite, fat storage and blood sugar levels.
A hormone suspected of causing weight gain must pass the causality test. If we inject this hormone in to people, they must gain weight. Only two hormones pass this test, Insulin and Cortisol.
Let’s understand what happens to the food we eat;
When we eat foods are broken down in the stomach and small intestine. Proteins are broken in to amino acids, fats in to fatty acids and carbohydrates in to simple sugars.
Our whole body is made of tiny cells and group of cells are allotted for different functions. All cells use blood sugar (glucose). Certain food such as refined carbohydrates raises blood sugar level more than other food.
Rise in blood sugar stimulates insulin release. Protein raises insulin levels as well, although its effect on blood sugars is minimal. Dietary fats tend to increase both blood sugars and insulin.
Insulin as a storekeeper
At meal times, ingested carbohydrate leads to more glucose being available than needed. Insulin helps move this flood of glucose (i.e. converted to glycogen) out of the blood stream in to storage (liver) for later use. But liver has limited storage space, once full excess carbohydrates will be turned in to fat.
Several hours after meal blood sugar and insulin level starts to drop. Less glucose is available for use by the muscles, brain and other organs. Then liver starts to release stored glucose in blood stream for energy. But that is also limited. During a prolonged fast your body can make new glucose from its fat stores.
This process happens every day. We eat, Insulin goes up, and we store energy as glycogen and fat. We fast, Insulin goes down and we use our stored energy. As long as feeding and fasting periods are balanced, this system also remains balanced. If we eat breakfast at 7 am and finish eating dinner at 7 pm, 12 hours of feeding balances 12 hours of fasting.
Now we know that insulin encourages sugar and fat storage. An imbalance between feeding and fasting leads to increase insulin, processed foods also hikes insulin level.
Take example of type 1 diabetic patients. Hallmark of this condition is severe weight loss. No matter how many calories the patient ingests, he or she can not gain weight. This is obvious, no or lesser insulin means body is not storing glycogen and fat. Patients are treated by daily injections of insulin. Drugs that raise insulin level cause weight gain.
Insulin Body set weight and obesity
Obesity develops when the hypothalamus orders the body to increase fat mass to reach the desired body set weight. Available calories are diverted to increase fat leaving the body short of energy. Body,s rational response is to try to get more calories. It increases hormonal signals of hunger and decreases hormonal signals of satiety. If we don’t eat body conserves calories needed for fat growth by shutting down other functions, and metabolism slows.
As a regulator of energy storage and energy balance, insulin is an obvious suspect as the body set weight regulator. If insulin causes obesity it must do so predominantly through its effect in the brain. Obesity is controlled in the brain through body set weight.
Insulin response differs greatly between lean and obese patients. Obese patients tends to have higher fasting insulin level, as well as exaggerated insulin response to food. It is possible that this hormonal activity leads to weight gain
high insulin level increase the body set weight.