Hypothyroidism is a condition in which the body lacks sufficient thyroid hormone. The main purpose of the thyroid hormone is to run the body's metabolism, which is why people with this condition will have symptoms associated with a slow metabolism. Hypothyroidism is an extremely common condition; over five million Americans have it. Also, as many as 10% of all women may have some degree of thyroid hormone deficiency. Unfortunately, when we talk about slow metabolism, we talk about a patient%26rsquo;s battles against their weight.
Possible causes of hypothyroidism
There are two fairly common causes of hypothyroidism.
1. Inflammation of the thyroid gland: This inflammation leaves a large percentage of the cells of the thyroid damaged and incapable of producing sufficient hormone. The most common inflammation of the thyroid is a disorder called autoimmune thyroiditis (also called Hashimoto's thyroiditis), a form of thyroid inflammation caused by the body%26rsquo;s own immune system.
2. Thyroid gland surgery: The second major cause of hypothyroidism is a previous medical treatment of the thyroid gland. The treatment of many thyroid conditions includes surgical removal of a portion of the thyroid gland. If the total mass of thyroid-producing cells left after the surgery is not enough to meet the needs of the body, the patient will develop hypothyroidism. In case of benign conditions, the purpose of the radioactive iodine therapy is to kill a portion of the thyroid to prevent goiters from growing larger, or producing too much hormone.
Rare causes of hypothyroidism
There are several other rare causes of hypothyroidism. The strangest condition of them causes a completely normal thyroid gland to fail to produce enough hormones because of a problem in the pituitary gland.
If the pituitary does not produce enough Thyroid-Stimulating Hormone (TSH) then the thyroid simply does not have the signal to make hormone.
Signs and symptoms of hypothyroidism
The signs and symptoms of hypothyroidism can vary widely, depending on the severity of the hormone deficiency. Also, symptoms can develop gradually over the years. At first, patients complain of barely noticeable symptoms such as fatigue and sluggishness.
But after some time, most patients develop more obvious signs and symptoms, including:
%26bull; Unexplained weight gain
%26bull; Muscle aches, tenderness and stiffness
%26bull; Pain, stiffness or swelling in joints
%26bull; Muscle weakness
%26bull; Heavier menstrual periods
%26bull; Increased sensitivity to cold
%26bull; Constipation
%26bull; Pale, dry skin
%26bull; A puffy face
%26bull; Hoarse voice
%26bull; Elevated blood cholesterol levels
%26bull; Depression
When hypothyroidism isn't treated, signs and symptoms can gradually become more severe, which could represent a bigger problem. Advanced hypothyroidism is a condition known as myxedema. This is a rare condition, but when it occurs it can be life-threatening.
Signs and symptoms include:
%26bull; low blood pressure
%26bull; decreased breathing
%26bull; decreased body temperature
%26bull; unresponsiveness
Hypothyroidism in children and teens
Although hypothyroidism most often affects middle-aged and older women, almost anyone can develop the condition, including infants and teenagers. Initially, babies born without a thyroid gland or with a gland that doesn't work properly may have only a few symptoms.
The most common symptoms of this congenital hypothyroidism, they may include:
%26bull; Yellowing of the skin and whites of the eyes (jaundice)
%26bull; Frequent choking
%26bull; Protruding tongue
%26bull; Constipation
%26bull; Poor muscle tone
%26bull; Excessive sleepiness
Untreated hypothyroidism in infants can lead to severe physical and mental retardation. As adults, they may exhibit several other symptoms such as:
%26bull; Poor growth, resulting in short stature
%26bull; Delayed development of permanent teeth
%26bull; Delayed puberty
%26bull; Poor mental development
What is the relationship between the thyroid and weight?
It has been acknowledged for a very long time that there is a complex relationship between thyroid disease, body weight, and metabolism. The thyroid hormone regulates metabolism, which is determined by measuring the amount of oxygen used by the body and, if the measurement is made at rest, is known as the basal metabolic rate (BMR). All the patients whose thyroid glands are not working should have low BMR, and those with overactive thyroid glands should have high BMR.
What is the relationship between BMR and weight?
All differences in BMR are associated with changes in energy balance which reflects the difference between the amount of calories one eats and the amount of calories the body uses. However, these connections are probably much more complex then we believe, and there is still much to discover. For example, when metabolic rates are reduced in animals by various means, these animals often do not show the expected excess weight gain. No one knows why.
Experts believe that the relationship between metabolic rates, energy balance, and weight changes is highly complex. The explanation probably is hidden in the fact that there are also many other hormones, proteins, and other chemicals that are very important for controlling energy expenditure, food intake, and body weight. That%26rsquo;s why no expert can truly and precisely predict the effect of changing thyroid state on any individual%26rsquo;s body weight.
What is the relationship between hypothyroidism and weight gain?
BMR in a patient with hypothyroidism is decreased, and therefore an under-active thyroid is generally associated with weight gain. Because nothing in medicine is simple, the weight gain in hypothyroid individuals is also complex, and not always related to excess fat accumulation. Most of the extra weight gained in hypothyroid individuals is due to excess accumulation of salt and water. Therefore, a massive weight gain should not be confused with hypothyroid-type weight gain.
How much weight can a patient expect to lose after the hypothyroidism is treated?
Because the great percentage of weight gain in hypothyroidism is accumulation in salt and water, when the hypothyroidism is treated a patient can expect a small weight loss. In most cases this weigh loss is less than 10% of body weight. Much like hyperthyroidism treatment, treatment of hypothyroidism with thyroid hormone should result in a return of body weight to what it was before hypothyroidism developed.
Because of the fact that hypothyroidism usually develops over a long period of time, it is fairly common to find that there is no significant weight loss after a successful treatment of hypothyroidism. The bottom line is, after hypothyroidism has been treated and thyroid hormone levels have returned to the normal range, the ability to gain or lose weight is the same as in individuals who do not have thyroid problems.