The thyroid gland influences nearly every system in the body, so when it is not functioning properly, symptoms can be wide-ranging and easy to mistake for other conditions. Understanding the common signs of thyroid dysfunction is the first step toward getting an accurate diagnosis.
Hypothyroidism Symptoms (Underactive Thyroid)
An underactive thyroid produces too little hormone, slowing down body processes. Common symptoms include fatigue and sluggishness, increased sensitivity to cold, constipation, pale and dry skin, brittle nails, hair thinning or loss, weight gain, puffy face, muscle weakness or aches, slowed heart rate, depression, impaired memory, and elevated blood cholesterol.
Hyperthyroidism Symptoms (Overactive Thyroid)
An overactive thyroid produces too much hormone, speeding up body processes. Symptoms include unintentional weight loss, rapid or irregular heartbeat, increased appetite, nervousness and anxiety, tremors in the hands, sweating, changes in menstrual patterns, increased sensitivity to heat, frequent bowel movements, enlarged thyroid (goiter), fatigue, muscle weakness, and difficulty sleeping.
When Symptoms Overlap
Some thyroid symptoms — such as fatigue, mood changes, and weight fluctuations — overlap with many other conditions including depression, menopause, anemia, and diabetes. This is why a blood test measuring TSH (thyroid-stimulating hormone) is essential for an accurate diagnosis rather than relying on symptoms alone.
Thyroid Symptoms in Women
Women are five to eight times more likely than men to develop thyroid disorders. Thyroid dysfunction can affect menstrual cycles, fertility, and pregnancy. Postpartum thyroiditis — a temporary inflammation of the thyroid after childbirth — affects about 5–10% of women and can cause alternating hypo- and hyperthyroid symptoms.
Getting Tested
If you experience several of these symptoms, speak with your doctor about a thyroid function test. A simple blood test measuring TSH, free T4, and sometimes free T3 can reveal whether your thyroid is functioning normally. Early detection and treatment can significantly improve quality of life.