Your thyroid may be small, but it plays an enormous role in your overall health.
When this important gland isn’t functioning properly, the warning signs can appear in ways many people never expect.
Feeling unusually tired? Gaining weight without changing your eating habits? Noticing that you’re colder than everyone else? These seemingly unrelated symptoms could have something in common: your thyroid.
Located at the front of your neck, the thyroid is a butterfly-shaped gland responsible for producing hormones that help regulate metabolism, energy levels, body temperature, heart function, and numerous other essential processes.
When the thyroid produces too little hormone, the condition is known as hypothyroidism, or an underactive thyroid. When it produces too much, it’s called hyperthyroidism, or an overactive thyroid.
Both conditions can affect your quality of life, and their symptoms are sometimes mistaken for ordinary aging, stress, or other health concerns.
Thyroid problems also become more common with age, particularly among women over 60.
Understanding the warning signs could help you recognize when it’s time to discuss thyroid testing with your doctor.
Here are seven symptoms worth paying attention to.
1. You’re Constantly Tired, Even After Getting Enough Sleep
Everyone feels exhausted occasionally. However, persistent fatigue that doesn’t improve with adequate rest may indicate an underlying medical issue.
One possible explanation is an underactive thyroid.
Thyroid hormones help your body regulate how it uses energy. When hormone levels are too low, normal bodily processes can slow down, leaving you feeling unusually sluggish.
You might notice that everyday activities require more effort than they once did. Tasks such as grocery shopping, cleaning the house, or taking a short walk may suddenly seem exhausting.
Some people also experience difficulty concentrating or maintaining their usual level of alertness.
Interestingly, an overactive thyroid can cause fatigue as well, sometimes because of disrupted sleep, muscle weakness, or increased demands on the body.
What to watch for: Ongoing tiredness that persists despite sufficient sleep, particularly when accompanied by other unexplained symptoms.
Fatigue can have many causes, including anemia, sleep disorders, medication effects, and depression. A medical evaluation can help identify what’s responsible.
2. Your Weight Changes Without an Obvious Explanation
Unexpected changes in body weight can sometimes reflect changes in thyroid function.
Your thyroid helps regulate metabolism, which influences how your body uses and stores energy.
When thyroid hormone levels are too low, metabolism may slow, contributing to modest weight gain. Some of this increase may result from fluid and salt retention.
You might notice your clothes fitting more tightly even though your eating habits and physical activity haven’t changed significantly.
The opposite can happen with an overactive thyroid.
When thyroid hormone levels become excessive, the body may burn energy faster, leading to weight loss even when appetite remains normal or increases.
However, thyroid conditions are not responsible for most weight changes.
What to watch for: Unexplained weight gain or weight loss, especially when accompanied by fatigue, unusual temperature sensitivity, or changes in heart rate.
Weight changes alone cannot establish a thyroid diagnosis, but they can provide useful information during a medical evaluation.
3. You’re More Sensitive to Cold or Heat Than Before
Have you started wearing sweaters when everyone else seems comfortable?
Or perhaps you’ve been sweating excessively in rooms that don’t feel particularly warm.
Your thyroid may be involved.
Thyroid hormones play an important role in regulating metabolism and heat production.
When the thyroid becomes underactive, the body may produce less heat, making you unusually sensitive to cold temperatures.
People with hypothyroidism sometimes complain of constantly cold hands and feet or needing extra blankets at night.
An overactive thyroid can cause the opposite problem.
Excess thyroid hormone increases metabolic activity, potentially making you feel overheated, uncomfortable in warm environments, or prone to excessive sweating.
What to watch for: A noticeable change in your tolerance for ordinary temperatures, particularly if the problem persists.
Temperature sensitivity can also be related to circulation problems, medications, menopause, or other medical conditions.
4. Your Hair Is Thinning or Your Skin Has Become Unusually Dry
Changes in your appearance can sometimes provide clues about what’s happening inside your body.
Thyroid hormones contribute to healthy skin and hair growth. When thyroid hormone levels become abnormal, both may be affected.
People with hypothyroidism may develop dry, rough skin or experience increased hair thinning.
Hair can become more brittle, and some individuals notice increased shedding.
An overactive thyroid may also contribute to hair thinning.
Although these changes can be concerning, they’re not necessarily permanent. Hair and skin symptoms related to thyroid dysfunction may improve once hormone levels are appropriately treated, although recovery can take time.
What to watch for: New or worsening hair thinning, persistent skin dryness, or noticeable changes in hair texture without an obvious explanation.
Aging, nutritional deficiencies, hormonal changes, and certain medications can produce similar symptoms. Thyroid testing may be appropriate when these changes occur alongside other warning signs.
5. Your Heartbeat Feels Unusually Fast, Slow, or Irregular
Your thyroid has a direct influence on cardiovascular function.
An overactive thyroid can cause the heart to beat faster than normal. Some people experience palpitations, which may feel like a pounding, fluttering, or racing heartbeat.
In certain cases, hyperthyroidism can contribute to abnormal heart rhythms, including atrial fibrillation, a condition associated with an increased risk of stroke.
An underactive thyroid may have the opposite effect, causing a slower-than-normal heart rate.
Because thyroid disorders become more common with age, changes in heart rhythm deserve particular attention among older adults.
What to watch for: New or persistent episodes of a racing heartbeat, irregular pulse, or unusually slow heart rate.
These symptoms should not automatically be attributed to the thyroid.
Heart rhythm changes can have several causes, including potentially serious cardiovascular conditions.
Seek emergency medical care if palpitations occur with chest pain, fainting, severe shortness of breath, or significant dizziness.
6. You’re Experiencing Mood Changes or Difficulty Concentrating
Thyroid problems don’t always produce obvious physical symptoms.
Sometimes, changes in mental well-being or concentration are among the first concerns people notice.
Hypothyroidism may contribute to depressed mood, forgetfulness, or difficulty concentrating.
Some individuals describe feeling mentally sluggish or having trouble remembering details that previously came easily.
Hyperthyroidism can produce a different set of symptoms, including nervousness, irritability, restlessness, and difficulty sleeping.
In older adults, thyroid dysfunction may occasionally present with less typical symptoms. An overactive thyroid, for example, may be associated with reduced appetite, fatigue, or withdrawal from normal activities.
This can make identifying the underlying condition more challenging.
What to watch for: Persistent changes in mood, concentration, memory, or sleep that seem unusual for you.
These symptoms can have many explanations. New or worsening memory problems should be evaluated rather than automatically blamed on aging or thyroid disease.
7. Your Digestive Habits Have Changed
One of the lesser-known effects of thyroid dysfunction involves digestion.
Thyroid hormones help regulate the movement of food through the digestive system.
When thyroid hormone levels are too low, digestive processes may slow down, contributing to constipation.
People with hypothyroidism sometimes experience persistent difficulty having regular bowel movements.
An overactive thyroid can produce the opposite effect.
Higher thyroid hormone levels may increase intestinal activity, leading to more frequent bowel movements or diarrhea.
These changes may occur alongside other symptoms such as weight fluctuations, temperature sensitivity, or changes in energy.
What to watch for: Persistent changes in bowel habits that cannot be explained by diet, medications, or another known condition.
Digestive changes are common and can have numerous causes. Seek prompt medical evaluation for concerning symptoms such as blood in the stool, severe abdominal pain, or unexplained weight loss.
Why Thyroid Problems Are Especially Important After Age 50
Although thyroid disorders can develop at almost any age, certain conditions become more common as people get older.
Women, particularly those over 60, have an increased risk of hypothyroidism.
Meanwhile, hyperthyroidism can sometimes be more difficult to recognize in older adults because symptoms may differ from those typically seen in younger individuals.
For example, instead of feeling noticeably nervous or overheated, an older person with hyperthyroidism might experience fatigue, appetite changes, or an abnormal heart rhythm.
This is one reason it can be important not to dismiss persistent symptoms as simply a normal part of getting older.
Undiagnosed or untreated thyroid dysfunction can also affect other areas of health.
Hypothyroidism may contribute to elevated cholesterol levels, while hyperthyroidism can increase the risk of certain heart rhythm problems and bone loss.
The encouraging news is that thyroid disorders are often manageable with appropriate medical care.
How Doctors Check Whether Your Thyroid Is Working Properly
If you recognize several of these symptoms, your healthcare provider may recommend a blood test to assess thyroid function.
The most common initial test measures thyroid-stimulating hormone, commonly called TSH.
TSH is produced by the pituitary gland and helps regulate thyroid hormone production.
A high TSH level often suggests an underactive thyroid, while a low TSH level commonly indicates an overactive thyroid. There are exceptions, so results must be interpreted in context.
Your doctor may also recommend additional testing, including:
- Free T4: Measures the amount of available thyroxine, an important thyroid hormone.
- T3: May be useful when evaluating certain cases of suspected hyperthyroidism.
- Thyroid antibody tests: Can help identify autoimmune thyroid conditions, including Hashimoto’s disease and Graves’ disease.
These tests can help doctors determine whether thyroid dysfunction is present and what might be causing it.
Treatment depends on the diagnosis.
Hypothyroidism is commonly treated with levothyroxine, a medication that replaces missing thyroid hormone.
Hyperthyroidism may require medication, radioactive iodine treatment, or surgery, depending on its cause and severity.
Avoid starting thyroid supplements or taking iodine in large doses without medical guidance. Excess iodine can worsen certain thyroid conditions.
When Should You Talk to Your Doctor?
Experiencing one of these symptoms does not necessarily mean you have a thyroid disorder.
Many thyroid-related symptoms overlap with other common health problems, and some people with thyroid disease experience few noticeable symptoms.
However, persistent changes in your energy, weight, temperature tolerance, heartbeat, mood, skin, or digestive habits deserve attention.
Consider scheduling an appointment if symptoms continue, become more noticeable, or begin interfering with your daily activities.
It’s particularly important to discuss your concerns if you have a family history of thyroid disease, an autoimmune condition, or previously diagnosed thyroid problems.
Your healthcare provider can determine whether testing is appropriate based on your symptoms, age, medical history, and individual risk factors.
The Bottom Line
Your thyroid helps regulate many of the processes that keep your body functioning properly.
When thyroid hormone levels become too high or too low, the effects can extend far beyond your neck.
Fatigue, unexplained weight changes, temperature sensitivity, thinning hair, irregular heartbeats, mood changes, and digestive problems can all be possible signs of thyroid dysfunction.
The most important thing to remember is that these symptoms are not proof of thyroid disease, but they shouldn’t automatically be ignored either.
Recognizing persistent changes and discussing them with a healthcare professional can help identify the underlying cause and determine whether treatment is needed.
Sometimes, a straightforward blood test can provide valuable answers and help you take the next step toward better health.
Medical Disclaimer: This article is intended for general educational and informational purposes only. It is not a substitute for professional medical advice, diagnosis, or treatment. Always consult a qualified healthcare professional regarding symptoms, medical conditions, or treatment decisions.
