Hypothyroidism is a condition associated with an underactive thyroid gland. When activity in the thyroid gland decreases, metabolism drops. This normally results in weight gain. Hypothyroidism is directly linked to insulin resistance, a condition linked to desensitized insulin cell receptors. Insulin is responsible for carrying blood sugar, or glucose, from the bloodstream and into the cells. So, when the cell receptors are inactive, glucose accumulates in the bloodstream.
Hypothyroidism
Hypothyroidism is a non-life-threatening condition of the thyroid gland that results in a low metabolic rate. When the body's metabolic rate drops, the body burns fewer calories. Excess nutrients are stored in the form of glycogen, or stored sugar, and fat. Though hypothyroidism sometimes is hereditary, it can also arise from medical treatments of an overactive thyroid, or hyperthyroidism. Hyperthyroidism may result in a sudden extreme and potentially lethal release of thyroid hormones into the bloodstream and Graves' disease, an eye disease in which the eyes bulge. A common treatment of hyperthyroidism is to remove the gland or destroy it with radioactive iodine. Removal or destruction of the gland results in hypothyroidism.
Insulin Resistance
Thyroid hormones help regulate the cells' uptake of nutrients. After eating a regular meal, fat, protein components and glucose enter the bloodstream. The pancreas releases insulin that binds to insulin cell receptors. This triggers transporters to move from the interior of the cells to the cell membrane. The transporters transport nutrients into the cells for energy use or storage. When the thyroid hormone levels are low, the insulin receptors can become resistant to insulin. When insulin binds to them, the signal does not transfer properly. As the cells receive nutrients at a slower rate, the brain interprets this as a state of starvation, urging you to consume more food.
Glucose in the Bloodstream
Cells are slow to absorb glucose and other nutrients from the bloodstream when communication between insulin and the interior of the cells is poor. So, in cases of insulin resistance, glucose slowly accumulates in the bloodstream. This can result in plaque formation on the inner walls of blood vessels, increasing the chance of cardiovascular disease. It also can lead to diabetes 2, a more severe case of insulin resistance. Finally, insulin resistance tricks the brain into thinking that it needs more food and becomes a cause of obesity.
Treatment
Synthetic thyroid hormone T4 is a standard prescription medicine for hypothyroidism. The medication supplies the hormones needed to ensure a healthy metabolism. In milder cases of hypothyroidism, the condition may be controlled with a diet designed to keep glucose levels low. Effective diets for hypothyroidism restrict both calories and simple carbohydrates, such as those that can be found in candy, white bread, white pasta and white rice. When your intake of calories and simple carbohydrates is restricted, the body will be more likely to use up free-floating sugar, preventing the consequences of low levels of thyroid hormones and insulin resistance.
