Dr Daryl Turner, a world authoritarian on Thyroid health explains in a lecture I attended, how most of us have some form of a Thyroid issue, that is not detectable by a TSH blood test.
Unless you are eating fish/seafoods 4 times a week, equivalent of 2.2 KGs then most likely you are Iodine deficient.
Most of the iodine that enters your body comes from the food that you eat. A smaller amount comes from the water that you drink. Iodine will enter your body if it is in the air that you breathe. The oceans are the most important source of natural iodine in the air, water, and soil. Iodine in the oceans enters the air from sea spray or as iodine gases. Once in the air, iodine can combine with water or with particles in the air and can enter the soil and surface water, or land on vegetation when these particles fall to the ground or when it rains. Iodine can remain in soil for a long time because it combines with organic material in the soil. It can also be taken up by plants that grow in the soil. Cows or other animals that eat these plants will take up the iodine in the plants. Iodine that enters surface water can reenter the air as iodine gases. Iodine can enter the air when coal or fuel oil is burned for energy; however, the amount of iodine that enters the air from these activities is very small compared to the amount that comes from the oceans.
Thats why we feel serenity and happiness when we are close to the sea, thats what our thyroid needs for full function.
Some forms of iodine can enter your body when placed on the skin. Iodine that enters your body quickly goes into your thyroid gland, a small important organ in your neck. Iodine is used in the thyroid gland to make hormones that are needed for growth and health. Almost all of the iodine in your body is in your thyroid gland. Iodine that does not go into your thyroid gland leaves the body in your urine in a few weeks to months. Small amounts of iodine can also leave your body in sweat or in breast milk. Iodine that leaves your body each day is usually replaced by the iodine that you eat in your food, so that the amount of iodine in your body is just enough to keep you healthy.
Wishing you happiness and hormonal balance.