Hypothyroidism vs Hyperthyroidism

The thyroid gland is a butterfly-shaped organ found at the center of the neck. It produces hormones that regulate nearly every organ in the body, including metabolism, breathing, heart rate, weight, digestion and mood. Certain conditions can cause the thyroid to produce too much or too little hormones.

Hypothyroidism or an underactive thyroid occurs when the thyroid gland does not make enough thyroid hormones to function well, slowing down metabolism and often leading to weight gain. Hyperthyroidism or an overactive thyroid gland produces too many hormones. If left untreated, hyperthyroidism can cause bone loss or an irregular heartbeat.

Hyperthyroidism vs Hyperthyroidism Symptoms

Hypothyroidism Hyperthyroidism
Weight gain Weight loss
Constipation Frequent bowel movements
Slowed heart rate Rapid or irregular heartbeat
Sensitivity to cold Sensitivity to heat
Muscle or joint pain Muscle weakness
Depression Nervousness and anxiety
Dry skin and thinning hair Hair loss
Decreased sweating Increased sweating
Heavy or irregular menstrual period Short and light periods
Fertility issues  


Doctors may do a physical exam, ask for personal and family history of health conditions, such as Hashimoto's disease and order blood and imaging tests to help rule out or diagnose thyroid issues. In some cases, a biopsy may be necessary. Possible treatments may include medicines (such as thyroxine or T3 replacement for hypothyroidism) and radioiodine therapy or thyroid surgery (for hyperthyroidism).

Can You Live a Normal Life with Thyroid Problems?

Both disorders can cause potentially life-threatening symptoms. While hyperthyroidism is treatable, hypothyroidism is a lifetime condition. However, with treatment, the outlook for both disorders is typically positive.

If you suspect your thyroid is not working as it should or believe you have symptoms of a thyroid condition, talk to an endocrinologist or hormone specialist for a proper diagnosis. Please do not delay care.

Medical News Today
National Library of Medicine

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