Answering common questions about thyroid disease
1/24/2022 by Rozalina McCoy, M.D.

Thyroid hormone is vital for healthy metabolism and overall health, and levels that are too low or too high harm physical, emotional and psychological health.
An estimated 20 million people in the U.S. have some form of thyroid disease. Up to 60% are unaware of their condition. Women are five to eight times more likely than men to have thyroid problems. One in 8 women will develop a thyroid disorder.
If you suspect you're having a problem with your thyroid, answers to these common questions may provide clarity:
What is thyroid disease?
With thyroid disease, your body produces too little or too much of the hormone thyroxine. When thyroid hormone levels are too low, patients can develop conditions such as heart failure, high cholesterol, depression or weight gain. When thyroid hormone levels are too high, patients can develop atrial fibrillation, anxiety or osteoporosis.
What are the symptoms of thyroid disease?
Symptoms that indicate you might have thyroid problems depend on whether you have too little or too much thyroid hormone:
- People with hypothyroidism, or not enough of the thyroid hormone
They commonly experience fatigue, intolerance to cold, weight gain, constipation, dry skin and irregular menstrual cycles. - People with hyperthyroidism, or too much thyroid hormone
They can experience anxiety, exaggerated emotions, weakness, tremors, heart palpitations, intolerance to heat, increased perspiration, irregular menstrual cycles and weight loss.
How are thyroid problems diagnosed?
Because symptoms of thyroid hormone imbalance are so common and are often caused by health conditions unrelated to thyroid disease, the first step is to evaluate the function of your thyroid using a test for thyroid stimulating hormone, or TSH. TSH is secreted by the pituitary gland in response to your body's levels of thyroid hormone. A normal TSH in adults is 0.3-4.2 milli-international units per liter. Levels can be higher in older than younger people.
If there isn't enough active thyroid hormone, TSH levels will rise as the pituitary gland tries to stimulate the thyroid to make more. If there's too much thyroid hormone, TSH levels fall.
People whose TSH is in the normal range are unlikely to have thyroid disease. If you're diagnosed with this condition, your provider will request that your TSH be checked periodically to monitor response to treatment.
How are thyroid problems treated?
Treatment for thyroid problems depends on whether your thyroid hormone levels are too high or too low.
- Hypothyroidism (hormone levels too low, TSH too high).
This condition is more common, and it tends to affect women more than men. It can be caused by an autoimmune thyroid disease, such as Hashimoto's thyroiditis; radiation to the thyroid or pituitary gland; certain medications; or other health conditions. This is treated with hormone replacement therapy. Your dose will be adjusted on the basis of regular TSH tests. - Hyperthyroidism (hormone levels too high, TSH too low).
It can be caused by autoimmune thyroid disease, such as Grave's disease; certain medications; hyperactive nodules; infection; or injury to the thyroid gland. The most common cause is taking too much thyroid hormone for hypothyroidism. Treating hyperthyroidism is more challenging than hypothyroidism, and treatment depends on the cause for elevated thyroid hormone levels. - Subclinical hypothyroidism/hyperthyroidism.
Some patients have abnormal TSH levels but normal thyroid hormone levels. These conditions generally don't need to be treated. However, there are important exceptions, which you should discuss with your health care provider, as treatment goals depend on a person's age and health. But all patients with subclinical thyroid disease should have their TSH and thyroid hormone levels checked regularly to detect if the condition has progressed or if there is a need for treatment.
It's important for all patients taking levothyroxine to have their TSH monitored and doses adjusted to maintain TSH in the normal range.
Keep in mind that symptoms that suggest thyroid problems are common and generally not caused by thyroid disease. It's important to discuss your symptoms and concerns with your health care provider, and be screened and treated for thyroid disease, if necessary.
Rozalina McCoy, M.D., M.S., is an endocrinologist and primary care physician in Primary Care in Rochester and Kasson's Division of Community Internal Medicine, Geriatrics and Palliative Care. She specializes in the management of Type 1 and Type 2 diabetes, osteoporosis, and thyroid disorders. Dr. McCoy also is a health services researcher who is passionate about improving the care of patients with diabetes, reducing their burden of treatment and hypoglycemia, and working with community-based organizations to help everyone access evidence-based health-promotion programs.