Symptoms & Diagnosis

Low Thyroid Symptoms: Complete List

Original article by Michael Teplitsky, MD

Author Michael Teplitsky, MD Published July 25, 2026 Read 7 min 1628 words

The symptoms may be 1. Very common 2. Less common 3. Not so common.

The symptoms may be 1. General (fatigue, feeling colder than others) and 2. Organ specific (dry, flaky skin, heavy menstrual period).

Very common symptoms include

Fatigue, feeling tired even after a good night sleep, getting tired easily. Would like to take a nap.

Weight gain, having problem controlling your weight.

Dry, flaky skin, sometimes with cuts, often irritated.

Excessive hair loss on the head, the body, and the outer third of eyebrow.

Depression, anxiety, brain fog, forgetfulness, reduced concentration.

Constipation.

Important points

1. Even though low thyroid can produce dozens of symptoms, there is no particular symptom that is diagnostic of low thyroid. In other words, there is no one symptom that only people with low thyroid have. All the thyroid symptoms, including very common, can be seen in other diseases and conditions.

2. Hypothyroidism does not happen suddenly, so the symptoms develop gradually and slowly. It may take months or even years before the person realizes that something is wrong. Until that happens, the person thinks that she is well and in good health.

3. The symptoms are caused by reduced metabolic activity because of lack of thyroid hormones.

How to use this report.

Print it out and read it carefully. If you see a symptom that you have, circle it or underline it. Each symptom counts. Depression, brain fog, forgetfulness, reduced concentration, not able to make decisions, procrastination – these are all separate symptoms. Count the number of circled/underlined symptoms. If it’s 5 or more, you probably have low thyroid. If it’s more than 10, you are very likely to have low thyroid. You should find and start working with an experienced doctor.

The symptoms

Let’s go from top of the body to the bottom and see what symptoms all the organs produce.

Skin becomes dry, scaly, with cuts and irritation. It may be pale and puffy under the eyes, or in the whole face, or hands and ankles. A yellow discoloration of the skin, almost like jaundice, can happen.

There is less sweating or no sweating at all. Hair becomes coarse and brittle, and there is hair loss on the head, on the body and the outer third of the eyebrows.

Brain and nervous system. Brain performs cognitive functions like thinking, decision making, mood and so on. Brain also controls autonomic functions like heart beats, breathing, blood pressure, etc. It also regulated hormones through hypothalamus and pituitary. Nerves control muscle movements, they also make it possible to feel things like touch, pain, temperature, and many other things.

People with hypothyroidism often have depression, lack of motivations, lack of desire to do anything, low interest in anything that is going on. Planning and decision-making get worse. There is a tendency to procrastinate. There is mental fog, memory gets worse, sometimes so bad that symptoms can get confused with dementia.

There can be sleep problems, from insomnia to sleep apnea.

Nerves can get damaged, developing neuropathy, pain, burning, tingling, numbness, usually in hands and feet. Restless leg syndrome and carpal tunnel syndrome can develop.

Eyes. Because of reduced function of tear glands (lacrimal glands), there is lack of lubrication and dryness, so eyes feel dry and gritty. The white of the eyes may be irritated. There may be a swelling or puffiness around the eyes. Blurry vision or even double vision may develop. There may be drooping of the eyelids and increased sensitivity to light.

Ears. There may be a feeling of fullness or clogged ears like when you fly in an airplane. There may be ringing in the ears or buzzing or some other noises. This is called tinnitus. Sometimes there is a complete hearing loss. People become more prone to ear infections. There may be a feeling of lightheadedness or even dizziness because of the vestibular apparatus located in each ear.

Mouth. Reduced production of saliva, which can give a feeling of dry mouth. Saliva contains immune elements that protect the mouth from inflammation and infections. Without enough saliva there can be mouth sores, gingivitis, periodontal disease, gum inflammation, cavities, and bad breath. A dental procedure, like a tooth extraction, may take longer to heal. There may be bone loss in the jaw. Tongue can become slightly swollen so you can see teeth marks if you stick the tongue out slightly. But in more severe cases tongue swelling can interfere with speaking and eating. Some people complain that their sense of taste has changed, that the food tastes differently.

Heart muscle pumps the blood so it can circulate through the network of arteries, capillaries and veins in the whole body.

In low thyroid, heart becomes weaker and does not pump the blood as effectively. The heart slows down which creates reduced circulation. It can be mild to severe even resulting in heart failure.

Thyroid hormones relax the muscles around the arteries, making it easier for the blood to flow, and reducing the blood pressure. Low thyroid makes arteries narrower, so the heart needs to work harder. Sometimes high blood pressure develops.

Because of heart weakness there is water retention, causing puffiness of the skin, fluid around the heart, fluid around the lungs and other places.

Low thyroid is an independent risk factor for hardening of the arteries and heart disease.

Lungs inhale air rich in oxygen and exhale stale air rich in CO2. This requires the action of the muscles inside the lungs and the muscle called the diaphragm, right under the lungs. All the muscles become weaker, so the lung function goes down. The air exchange is less efficient. There may be some fluid accumulating around the lungs, called pleural effusion. This may lead to shortness of breath, especially on exertion, but even at rest in severe cases. There is also an increased risk of respiratory infections.

Liver produces a number of important proteins, it is necessary for sugar metabolism, it is involved in detoxification, it produces bile and cholesterol, It converts T4 to T3, it is involved in metabolism of medications, it is important for normal blood clotting and does dozens of other things. Hypothyroidism interferes with all that, it interferes with detoxification, worsens sugar control, increases cholesterol, makes bile thicker, increases the likelihood of gallstones. It can also increase liver enzymes in the blood test. And it can cause fat accumulation in the liver and cause Non-Alcoholic Fatty Liver Disease or NAFLD. Medications are usually removed by the liver, so if you are taking certain medications and have low thyroid, you should check with your doctor if you need to decrease the dose.

Kidneys remove toxins and extra water. Low thyroid causes water retention. This leads to puffiness of the face, puffiness of eyelids, swelling of the hands and feet, carpal tunnel syndrome. Your tongue becomes slightly swollen and presses against the teeth.

Bladder muscle becomes weaker, so it does not push out urine as effectively. This could lead to more frequent urinations, sort of like in men with enlarged prostate. It also increases the risk of the urinary tract infections, especially in women.

Kidneys regulate minerals like sodium, potassium, chloride, zinc, magnesium, calcium and many others. In hypothyroidism, sodium, potassium and other minerals may be low on the blood test.

Ovaries and testicles. Low thyroid causes decreased libido in both men and women. It also causes infertility or difficulty conceiving in both men and women.

Women can have problems with menstruations, they can become less frequent or irregular or last longer than usual. Often, women have very heavy periods, with so much blood loss that it can cause anemia. There are also problems with ovulation, it may happen irregularly or stop altogether. This also can cause infertility.

In men, there is decreased testosterone production and decreased sperm production. And the sperm is not as active as it should be, which also contributes to fertility problems.

Muscles become painful and weak. Joints become painful and stiff, pain usually affects hands, knees, other large joints. It can be so bad that it is confused with Rheumatoid Arthritis. Low thyroid reduces bone turnover, so new bone tissue is made more slowly while old, dead tissue is not removed properly, making the bones more brittle.

Immune system consists of many different types of white cells and the organs that make them and train them. It protects you against enemies, like bacteria, viruses, toxins and everything that is not part of you. Or even your own cells if they become abnormal, like cancer cells.

All this requires a lot of energy, and all while cells suffer when thyroid is low. Which makes the immune system weaker. Which means you become more susceptible to infections, like frequent colds and flues, sinusitis, sore throat, canker sores. And because immune system also protects you from cancer, the risk of cancers increases.

Immune system is responsible for 2 important thyroid conditions. One is Hashimotos, which is the #1 cause of low thyroid in US. Another is Graves disease, which causes overactive thyroid, a condition also called hyperthyroidism. In both cases there is nothing wrong with the thyroid, it’s the overactive immune system that does all the damage and causes various auto-immune diseases, such as Hashimoto’s, scleroderma, rheumatoid arthritis and many others.

GI tract. Gi tract starts in the mouth and ends at the anus. The intestine slows down in hypothyroid, which results in constipation. It also causes overgrowth of bad bacteria, yeasts, Candida and parasites, also called dysbiosis. This causes gut inflammation, leaky gut syndrome, which makes allergies worse.

There are many other symptoms, but the main thing to remember is that everything becomes sluggish and every part of the body and every organ is affected.

FAQ from The Metabolic Journal Editors

These questions are based on this article and related Dr. Teplitsky articles.

What symptoms does Dr. Teplitsky connect with low thyroid?

His articles emphasize fatigue, weight gain, feeling colder than others, constipation, hair loss, depression, brain fog, and a long list of less obvious symptoms.

Why can diagnosis be difficult?

Many symptoms overlap with other conditions, and Dr. Teplitsky argues that a narrow lab interpretation can miss some patients who still need a careful thyroid evaluation.

How can I book an appointment with Dr. Teplitsky?

Call Dr. Teplitsky’s office at 718-769-0997 to book an appointment or ask about availability.

Medical Disclaimer: This content is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare provider before making changes to your health regimen.