But a noticeable change from your normal pattern, especially alongside other symptoms, can be worth discussing with a healthcare professional.

4. Your Heartbeat Feels Different

Thyroid hormones influence the cardiovascular system.

An overactive thyroid can cause the heart to beat faster than normal.

Some people may notice:

• A racing heartbeat

• Palpitations

• Pounding in the chest

• An unusually fast resting pulse

• Irregular or uncomfortable heartbeat sensations

Hypothyroidism can have different cardiovascular effects and may be associated with a slower heart rate in some people.

Palpitations shouldn't automatically be attributed to the thyroid.

Caffeine, anxiety, dehydration, certain medications, anemia, abnormal heart rhythms, and other conditions can also cause them.

If you experience a new or persistent change in your heartbeat, especially with chest pain, severe shortness of breath, fainting, or severe dizziness, prompt medical evaluation is important.

5. Your Hair or Skin Starts Changing

The thyroid affects many tissues throughout the body, including the skin and hair.

When thyroid hormone levels are abnormal, some people may notice changes in the appearance or texture of their hair.

Possible changes include:

• Thinning hair

• Increased hair shedding

• Dry or brittle hair

• Coarser hair texture

• Thinning of the outer portion of the eyebrows

Hypothyroidism may also be associated with dry, rough, or unusually cool skin.

Some people may notice that their skin feels less soft or that it becomes more prone to dryness.

Hyperthyroidism can produce different skin changes, including warm, moist skin due to increased sweating.

These symptoms aren't specific to thyroid disease.

Hair loss, for example, can occur after illness, during periods of significant stress, because of nutritional deficiencies, hormonal changes, certain medications, or other medical conditions.