Hypothyroidism, or a decreased function of the thyroid gland due to decreasing levels of thyroid hormone has multiple manifestations. Low thyroid hormone production can result in depression, constipation, weight gain, headaches, rigid brittle striated nails, rough dry skin, menstrual irregularities and fluid retention. Hypothyroidism can also present with poor circulation, slow speech, anxiety and panic attacks, poor memory and an inability to concentrate. Signs of low thyroid function also include cold hands and feet, cold intolerance, reduced heart rate, slow movements and morning stiffness. A puffy face, swollen eyelids and a decreased sexual interest are also noted.
Another part of the picture includes insomnia, fatigue, low body temperature, a horse, husky voice, sparse coarse dry hair, muscle cramps and drooping eyelids. If you notice thin eyebrows or loss of eyebrow hair especially on the outer boarders of the brow, this sign can be diagnostic of hypothyroidism. Disease states associated with hypothyroidism include hypercholesterolemia, infertility, PMS, hyperinsulinemia, fibrocystic breast disease, nutritional imbalances and myxedema. Thyroid hormones interact with most systems in the body and decreased function also can precipitate iron deficiency anemia, B12 deficiency, bipolar disorders, heart disease, asthma, hypertension and gall stones as well as erectile dysfunction in men.
Low thyroid function can result in a thickened and weakened bone structure resulting in osteoporosis. If these individuals are treated with thyroid replacement, remodeling to stronger bones occurs within 6-12 months.
The two main thyroid hormones are T3 and T4. The thyroid gland produces T4 which is converted into the active hormone T3. Certain cofactors are needed to initially produce T4. If the patient is deficient in zinc, copper, Vitamins A, B2, B3, B6 and C there will be decreased production of T4. The conversion of T4 to T3 requires the action of a group of enzymes called 5’deiodinases. Elements that affect the production of this enzyme include selenium deficiency, stress, heavy metal toxicities including cadmium, mercury or lead, starvation, inadequate protein intake, high carbohydrate diet, elevated cortisol levels, chronic illness, decreased kidney or liver function and inflammation. there factors that can cause an inability to convey T4 into T3 include nutrient deficiencies including iodine, iron, selenium, zinc and Vitamins A and B. Medications including beta blockers, birth control pills, estrogen, lithium, theophylline and chemotherapy can also cause this decreased conversion. Diet and nutrition plays a big role. Too many cruciferous vegetables, low protein, low fat, low c carbohydrate, excessive alcohol, walnuts and soy can all cause decreased conversion of T4 to T3. Finally, aging, diabetes, lead, mercury, pesticides, radiation and stress all play an important role in decreasing this important conversion. This is a lot to digest, but the thyroid gland is very important for overall metabolic regulation and also very sensitive to many factors. Tomorrow, we delve deeper and talk about T3.