You may assume that feeling tired, depressed, mentally foggy, constipated and heavy are just due to your overstretched schedule, stress and sedentary lifestyle. But if these symptoms make it hard to accomplish daily tasks or persist even with improved nutrition, hydration and regular exercise, talk to your doctor—one possible answer may involve your thyroid.

“Thyroid disease includes a cluster of autoimmune disorders that cause low levels of thyroid hormone (hypothyroidism) or high levels (hyperthyroidism),” says Dr. Christy Richardson, an endocrinologist with SSM Medical Group at DePaul Health Center. “Hypothyroidism can occur in men or women at any age, but it’s most common in middle-aged women. Hyperthyroidism also is more common in women, and the autoimmune type tends to occur early in their 20s. Other causes of hyperthyroidism increasingly occur with age, and thyroid disease tends to run in families.”

Hypothyroidism may be the culprit for the cluster of symptoms noted above, as well as intolerance to cold temperatures, fluid retention, hair loss, decreased heart rate, dry skin, coarse hair, brittle nails, cholesterol abnormalities and infertility. Low levels of the hormone produced by the thyroid leads to decreased metabolic function, which affects almost every system in the body and can result in all these physical issues.

The most common form of hypothyroidism, the autoimmune disease known as Hashimoto’s thyroiditis, is estimated to affect between 0.1 percent and 5 percent of all adults in Western countries. If hypothyroidism is suspected, your physician will order blood tests that check levels of thyroid hormones. If these levels are subclinical (too low) and hypothyroidism is diagnosed, treatment typically involves taking a prescription thyroid hormone in order to bring levels back to normal.

“Most thyroid diseases are not curable but are easy to manage,” says Dr. Veronica McGregor with Mercy Clinic Endocrinology. However, she notes that ‘not every weight gain, fatigue, hair loss, etc., means thyroid disease. Consider if you are sleeping at least seven hours a night, if you are exercising regularly, and if you are eating healthy foods and normal portions.”

“Hyperthyroidism is pretty much the opposite,” Richardson says. Symptoms include rapid heartbeat, heat intolerance, anxiety, nervousness, insomnia, weight loss, frequent bowel movements, tremors, racing thoughts and an inability to concentrate. If hyperthyroidism is detected, treatment may involve medication, radioactive iodine therapy or surgical removal of the thyroid.

“An annual visit with your primary-care doctor will usually include a thyroid exam,” Richardson adds. “Screening should probably start at age 35 and then occur every two to five years, or as needed, should signs or symptoms arise.” Once thyroid disease is diagnosed, patients’ levels are checked more regularly to ensure their treatments are maintaining proper thyroid hormone levels.

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