Many patients with thyroid hypofunction are struggling with their inability to lose weight, a losing weight for them is a challenge. The most recent research focuses on the evaluation of two key hormones - leptin and T3.
It was found that the hormone leptin is a key regulator of body weight and our metabolism. It is secreted by fat cells, leptin levels increase with the accumulation of fat. Increased leptin secretion that occurs with weight gain, is usually fed back to the hypothalamus as a signal that there is sufficient energy stores. It stimulates the body to burn fat rather than continue to store excess fat and stimulates the thyroid gland.
Studies show that the majority of overweight people have difficulty losing weight because of varying degrees of leptin resistance, where leptin has a decreased ability to affect the hypothalamus and regulate their metabolism. It means that the hypothalamus sends a signal for hunger, so multiple mechanisms are activated and begin increasing body fat as the body tries to fight the state of hunger. Mechanisms that are activated also act to increase appetite, increase insulin resistance and inhibition of lipolysis (breakdown of fat). The result? Onset of obesity and weight loss becoming more difficult.
When you have reduced thyroid function and you do not produce enough hormones, the effect is a slow metabolism. Furthermore, the delay slows down all processes in your body from digestion to hair growth. This in turn leads to weight gain and difficulty with losing weight. In this case, you have to be very careful with your diet, because poor nutrition can further aggravate your situation.
In addition to everything said here, people with an underactive thyroid gland (hypothyroidism) often are likely to feel tired, making exercises much more difficult for them because they just have a lot less energy. With slower metabolism and less energy loss becomes an almost unattainable goal.