Thyroxine and Triiodothyronine
The function of the thyroid gland is to take the iodine found in food, and convert it into thyroid hormones. These thyroid hormones are Thyroxine and Triiodothyronine. Thyroxine increases the metabolic rate in your body and it plays a critical role in brain function as well as digestion, heart and muscle function and the maintenance of bones. Triiodothyronine plays an important role in regulating your weight, body temperature, muscle strength and most importantly, your brain development and health.
hypothyroidism
Low Thyroid function, also known as hypothyroidism may present itself in many forms including fatigue, weight gain and feeling cold. Starting with one of the most common: fatigue. The thyroid hormones control energy balance and individuals with low thyroid hormones will feel exhausted and sluggish. Another symptom of hypothyroidism is weight gain and this is due to the thyroid signaling the liver, muscles and fat tissue to hold onto calories. Heat is a byproduct of burning calories so when the thyroid has a low function, it is having the opposite effect, causing you to feel cold.
Iodine deficiency
Iodine deficiency is on the rise in the U.S. and is one of the leading causes of thyroid issues. The symptoms of iodine deficiency are very similar to the symptoms of hypothyroidism such as obesity, joint pain, infertility and heart disease. Most countries rely on fortified iodine as an adequate dietary intake through iodized salts but the salt used in processed foods typically do not contain iodine. You may add iodized table salt to your meals as well as eat iodine-rich foods like fish, seaweed, dairy and eggs.