[TBD]Understanding different kinds of thyroid problems

Introduction

Thyroid is a gland. The thyroid gland controls rate of use of energy sources, protein synthesis, and controls the body's sensitivity to other hormones.

It participates in these processes by producing thyroid hormones, the principal ones being thyroxine (T4) and triiodothyronine (T3), which is more active. These hormones regulate the growth and rate of function of many other systems in the body. T3 and T4 are synthesized from iodine and tyrosine.

Overactive thyroid (Hyperthyroidism)

Hyperthyroidism occurs when the gland produces excessive amounts of thyroid hormones, the most common cause being Graves' disease—an autoimmune disorder. It is defined as an overproduction of the thyroid hormones T3 and T4.

Underactive thyroid (Hypothyroidism)

hypothyroidism is a state of insufficient thyroid hormone production.

Hypothyroidism is the underproduction of the thyroid hormones T3 and T4.

Physiological action of T3 and T4

It increases oxygen consumption of all tissues except brain, uterus, testis (though it is important for normal fertility) lymph node, spleen, and its source, anterior pituitary, mainly by its action on sodium potassium pump and fat metabolism.

It is helps in conversion of carotene into vitamin A in hepatic cells, therefore, hypothyroidism may lead to high levels of carotene in the blood, resulting in yellowish tint of only skin (and not the mucous membrane, like sclera).

Many cardiovascular effects are reported. Increased peripheral resistance, increased rate and force of heart beat occurs by effects of circulatory T3 .

It increases carbohydrate absorption.

It is also reported to decrease cholesterol levels.

Reference

https://en.wikipedia.org/wiki/Thyroid