19 Symptoms of Thyroid Conditions and What They Mean

Signs of thyroid problems vary depending on the cause. Hyperthyroidism (overactive thyroid) may cause symptoms like diarrhea, heat sensitivity, and weight loss. Hypothyroidism (underactive thyroid) can cause constipation, cold sensitivity, and weight gain.

Any of these and other thyroid symptoms could also be early warning signs of thyroid disease. Remember that just because you have one of these symptoms, it does not mean you have a thyroid problem. It is best to consult a healthcare provider for a proper diagnosis.

Brain fog, or a decline in cognitive function, could be a symptom of a thyroid problem like hypothyroidism.

The following symptoms related to brain fog can persist after your TH levels are stable at normal levels:

• Difficulty focusing
• Forgetfulness
• Low energy
• Sleepiness

Thyroid hormone (TH) influences appetite. Too much TH, which occurs with hyperthyroidism, can increase your appetite. Even though hyperthyroidism is typically associated with weight loss, you may gain weight due to increased appetite.

Appetite-related symptoms are not the same for everyone. Adults aged 60 years or older may lose their appetite instead of increasing it.

Your thyroid is closely connected to digestion. An overactive thyroid gland can cause frequent bowel movements or diarrhea.

An underactive thyroid can lead to constipation. When something disrupts the production of TH, your digestive processes may slow down.

TH helps regulate metabolism, so weight gain and loss are common thyroid disease symptoms. Hypothyroidism typically causes weight gain. People tend to put on more weight when the thyroid is underactive because their metabolism is lower. Extreme weight gain is rare in hypothyroidism.

Hyperthyroidism usually causes weight loss. Your metabolism is working at a high rate when your thyroid is overactive. The severity of weight loss relates to the severity of hyperthyroidism. You likely will not see as much weight loss if your thyroid is only slightly overactive.

How your thyroid functions affects how you perceive temperature. One hypothyroidism symptom is trouble tolerating the cold. When an underactive thyroid slows down body systems, your cells may have less energy to burn. Less energy means less heat.

People with hyperthyroidism may have trouble tolerating heat. An overactive thyroid puts your cells that produce energy into overdrive.

Sleep disorders related to thyroid problems include:

• Insomnia: High TH levels can worsen conditions like anxiety and depression, which worsen insomnia. Hypothyroidism may not directly cause insomnia but can affect sleep quality through other complications like muscle and joint pain.
• Obstructive sleep apnea: Many people with obstructive sleep apnea, which disrupts breathing during sleep, also have hypothyroidism. How exactly these two conditions are related is unclear.
• Restless legs syndrome (RLS): Hyperthyroidism and hypothyroidism can contribute to RLS, which causes a strong urge to move your legs when you lay down. Treating TH levels may provide symptom relief.

Thyroid disease can cause several problems with your skin, nails, and hair. You also have a high risk of thyroid disease if you have skin conditions like vitiligo, hives, or alopecia areata (hair loss).

Skin and nail symptoms may include:

• Brittle, dry, thick nails with ridges; nails that peel, crumble, or break easily; or soft, shiny nails
• Changes in how quickly nails grow
• Curved swollen fingertip and thickening above the nail
• Deep lines on your palms and soles
• Discolored, dry, pale, or itchy skin
• Protruding eyes
• Rashes, especially in skin creases
• Slow-healing wounds
• Sweating less or more than before
• Widening nose

Thyroid disease can affect the growth and texture of your hair. Hair symptoms may include:

• Changes in hair growth rate
• Coarse, dull, dry, and brittle hair that breaks off easily
• Hair loss and bald patches
• Itchy, dry scalp and dandruff
• Less hair in places like your arms and legs
• Soft and fine hair that sheds a lot
• Thinning or missing hair on the outer edge of your eyebrow

Keep in mind that hair loss can happen for a variety of other reasons­­, like childbirth or overuse of hair products. See a healthcare provider to get help determining the cause.

Your thyroid is involved in several bodily functions, from breathing and heart rate to weight, digestion, and mood. When it makes too much or little TH, you may feel extra tired or lack energy.

Fatigue can be both a symptom of hypothyroidism and hyperthyroidism. It can affect you mentally and physically. It may be a clue that your thyroid is underactive or overactive if you are still tired in the morning or all day after a full night’s sleep.

Heart palpitations can signify too much TH. They can feel like your heart is fluttering, skipping a beat or two, or beating too hard or quickly. You may notice these feelings in your chest or at pulse points in your throat or neck. About 10-25% of people with hyperthyroidism have a rapid heartbeat.

Hypothyroidism can also cause different effects on the heart. You may experience symptoms like:

• Constricted blood vessels
• Fluid retention, which causes swelling
• Heart failure (if symptoms are untreated)
• High cholesterol levels
• Hypertension (high blood pressure)
• Slow heart rate

A change in your voice or a lump in your throat could signify a thyroid disorder. A thyroid nodule is a lump that grows in the thyroid, which may be benign (non-cancerous) or malignant (cancerous). A lump in your throat could be due to thyroid cancer, which can cause hoarseness or other voice changes that do not go away.  

Your thyroid can also become enlarged and cause a goiter, which can indicate either hyperthyroidism or hypothyroidism. Swelling or inflammation of the thyroid gland can be a sign of thyroiditis, including Hashimoto’s disease or postpartum thyroiditis.

As your levels of TH change, your mood can also change. People with an overactive thyroid may develop nervousness, irritability, and mood swings.

People with an underactive thyroid may have a higher risk of anxiety and depression. Make sure a healthcare provider knows about your hypothyroidism if you are taking medication for depression. Tricyclic antidepressants may cause complications for people with hypothyroidism.

Mysterious or sudden muscle changes can signify thyroid disease. Hyperthyroidism can cause muscle weakness, myalgia (muscle pain), and muscle wasting in the shoulder or pelvic girdle.

You may experience muscle or joint pain if your thyroid does not produce enough TH. About 80% of people with hypothyroidism have hypothyroid myopathy, which can severely affect muscles and limit mobility if untreated.

Thyroid dysfunction can have various effects on the reproductive system—and vice versa. People who have been pregnant or reached menopause may be more likely to develop thyroid disease than others.

Too much or too little TH can throw off your menstrual cycle. You may have light, heavy, or irregular periods. Thyroid disease can also cause amenorrhea, or when your periods stop for several months or longer. You may also go into menopause early—before 40 years old—if you have thyroid disease.

Hypothyroidism can cause excess prolactin, the hormone that makes breast milk. Too much prolactin can prevent ovulation, which causes difficulties if you are trying to get pregnant.

Thyroid problems also can affect the health of your pregnancy. Untreated thyroid disease may cause the following pregnancy complications:

• Low birth weight
• Miscarriage
• Preeclampsia (high blood pressure during pregnancy)
• Premature birth

Having little or no desire for sexual activity could be a side effect of hypothyroidism and hyperthyroidism. A dysfunctioning thyroid may impact the following:

• Arousal
• Desire
• Orgasm
• Satisfaction

Some people with thyroid disorders also have dyspareunia (pain during intercourse). Too little TH could contribute to low libido (sexual desire), but the impact of other symptoms—weight gain, low energy, and body aches and pains—could also play a role.

Your thyroid is a small gland in your neck shaped like a butterfly and greatly impacts your body. It produces TH, which affects your metabolism, heartbeat, and more.

There are a few health conditions that are associated with the thyroid, such as:

• Goiter, or an enlargement of the thyroid
• Hyperthyroidism
• Hypothyroidism
• Thyroid cancer
• Thyroid nodules
• Thyroiditis, or swelling of the thyroid

Look at your neck to check your thyroid at home and see if you can detect any signs of thyroid swelling. Follow these directions from the American Association of Clinical Endocrinologists:

• Use a hand mirror, and look at the area of your neck above your collarbone and below your larynx (voice box). This is where your thyroid is.
• Keep looking at your thyroid in the mirror and tip your head back.
• Take a drink of water and swallow.
• Observe your neck when you swallow. Look for any bulges or protrusions in the thyroid area.
• Repeat this several times. Remember, your thyroid is just above your collarbone. Try not to confuse it with your Adam’s apple.

Talk to a healthcare provider about any protrusions or bulges you find. They can evaluate any areas of concern, diagnose underlying conditions, and prescribe treatment.

Signs may take months or years to appear. Take early warning signs of thyroid problems seriously. Anything that is lumpy or suspicious warrants getting a check from a healthcare provider. They may do blood tests, including a thyroid-stimulating hormone (TSH) test or free T3 and free T4 tests.

Thyroid symptoms can cause other complications, so it is important to seek treatment. Hypothyroidism, for example, can contribute to high cholesterol.

Diagnosing thyroid problems may be hard since symptoms can be similar to other conditions. Knowing the potential signs of thyroid disorders, like sexual dysfunction, irregular periods, and mood changes, can help you get treatment.

Take note of symptoms if you suspect you have a thyroid problem or have a family history of thyroid disease. Notify a healthcare provider if you are concerned about thyroid disease.