Thyroid Problems in Adults: Symptoms That Are Easy to Miss

Your thyroid is a small, butterfly-shaped gland at the base of your neck, but it has an outsized job. The hormones it makes help set the pace for nearly every system in your body — your heart rate, how quickly you burn energy, your body temperature, your digestion, and even your mood. When the thyroid makes too little or too much hormone, the effects can be wide-ranging and surprisingly easy to blame on something else.

When the Thyroid Runs Slow (Hypothyroidism)

An underactive thyroid is more common, especially in women and adults over 60. Because symptoms build slowly, many people assume they’re just getting older or busier. Common signs include:

• Fatigue that sleep doesn’t fix
• Feeling cold when others are comfortable
• Weight gain without a change in eating habits
• Constipation
• Dry skin, brittle nails, or thinning hair
• Low mood, brain fog, or forgetfulness
• Heavier or irregular menstrual periods
• Muscle aches or stiffness

When the Thyroid Runs Fast (Hyperthyroidism)

An overactive thyroid speeds things up. It’s less common but can be just as disruptive:

• A racing or pounding heartbeat, or palpitations
• Anxiety, irritability, or feeling on edge
• Unexplained weight loss despite a normal or increased appetite
• Feeling hot and sweating more than usual
• Trouble sleeping
• Shaky hands
• More frequent bowel movements
• Bulging or irritated eyes, in some types

Why These Symptoms Get Missed

Almost every symptom on those lists has other possible explanations — stress, menopause, depression, poor sleep, or a busy season of life. That’s exactly why thyroid problems can go undiagnosed for a long time. An internist’s job is to look at the whole pattern rather than any single complaint, and to test when the pattern fits.

How Thyroid Problems Are Diagnosed

The main screening test is a blood test called TSH (thyroid-stimulating hormone). TSH is released by the brain to tell the thyroid how hard to work. A high TSH usually means the thyroid is underactive; a low TSH usually means it’s overactive. Depending on the result, your doctor may check additional thyroid hormone levels or antibodies that point to autoimmune causes like Hashimoto’s thyroiditis or Graves’ disease. If your doctor feels a lump or enlargement in your neck, an ultrasound may be recommended.

Who Should Be Especially Alert

• Women, particularly during and after pregnancy and around menopause
• Adults with a family history of thyroid disease
• People with other autoimmune conditions, such as type 1 diabetes or rheumatoid arthritis
• Anyone taking medications known to affect the thyroid
• Adults who’ve had radiation to the neck or thyroid surgery

Treatment Is Usually Straightforward

Most thyroid conditions are very manageable. An underactive thyroid is typically treated with a daily hormone replacement, with periodic blood tests to fine-tune the plan. An overactive thyroid has several treatment approaches depending on the cause. In both cases, ongoing follow-up matters, because thyroid needs can shift with age, weight changes, pregnancy, and other medications.

Don’t Write Off How You Feel

If you’ve been feeling “off” for months and can’t explain why, it’s reasonable to ask whether your thyroid has been checked recently. It’s a simple blood test, and an answer — whether it’s the thyroid or something else — is a lot better than continuing to push through.

This article is for general education and isn’t a substitute for medical advice. If you have symptoms that are severe, sudden, or worrying, call 911 or seek emergency care.