Hypothyroidism

• Hypothyroidism is a condition in which your thyroid gland produces insufficient amounts of thyroid hormone. As this thyroid hormone regulates metabolic processes, a deficiency can result in a number of undesirable symptoms, including unplanned weight gain and chronic fatigue. Note that hypothyroidism is a lasting condition that must be treated with medication and is not a transient problem.
  
  

Metabolism and Diet

• Put simply, your metabolism is the speed at which your body's "engine" is running, determining its rate of fuel (calorie) consumption. Although many people qualify metabolism in static terms (e.g. "I have a slow metabolism"), the fact is that metabolism is an ever-evolving process. Under the right conditions, someone with a self-diagnosed innately "slow" metabolism will burn calories just as quickly as someone with a "fast" metabolism. Some factors that can influence your metabolic rate include the quantity of caloric consumption, duration of exercise and intensity of exercise.
  
  

Diet's Effects on Metabolism

• Metabolism mirrors caloric intake---this means that when you consume more daily calories, your metabolism naturally will run faster. Conversely, where you are consuming fewer calories (as on a diet), your metabolism will slow down. Prolonged caloric deprivation, as with an extremely low-calorie diet of extended duration, can cause symptoms that might appear to be akin to hypothyroidism, such as the inability to lose more weight, fatigue and heightened sensitivity to cold.
  
  

Diet and Hypothyroism

• Although these symptoms might seem to indicate hypothyroidism, that does not mean you are so afflicted. Metabolic slowdown from dieting is a temporary situation that will reverse itself upon consumption of a larger quantity of food. An individual with hypothyroidism, on the other hand, will not respond as well to conventional metabolic boosters such as merely increasing caloric intake and activity level. According to the Medical Center of the University of Maryland, the causes of hypothyroidism include antibodies attacking the thyroid following medical treatment for hyperthyroidism (overproduction of thyroid hormone) and goiter (where your diet has insufficient quantities of iodine, not insufficient calories).
  
  

Considerations

• If you are still convinced you have developed hypothyroidism from your low-calorie diet, consider consuming additional iodine-containing foods to assist your thyroid in producing hormones. According to the Medical Center at the University of Maryland, foods that can help with hypothyroidism include whole grains, vegetables, beans and cold-water fish. However, the easiest solution likely is to cease your diet for a few weeks and boost your daily caloric intake.