How To Differentiate Hashimoto’s Disease From Hypothyroidism?

Hypothyroidism is common, affecting approximately 5%¹ of the US population. Some people diagnosed with hypothyroidism may also suffer from Hashimoto's thyroiditis. 

Although these diseases are related, they are different. Knowing the difference can help you receive the correct treatment.

Have you considered clinical trials for Hashimoto's disease?

We make it easy for you to participate in a clinical trial for Hashimoto's disease, and get access to the latest treatments not yet widely available - and be a part of finding a cure.

What is hypothyroidism?

Hypothyroidism, also known as an underactive thyroid, is a health condition where the thyroid gland fails to produce enough hormones.

The thyroid gland is a butterfly-shaped endocrine gland situated in the lower front of the neck. Its main task is to produce thyroid hormones that are secreted into the blood then transported to every body tissue.

The thyroid hormone regulates the rate at which calories are burned, affecting weight loss and weight gain. The hormone hugely determines energy production in the body, ensuring that crucial body organs like the brain, muscle, and heart function correctly.

In the earlier phases, hypothyroidism doesn’t have any noticeable symptoms. However, if untreated, the condition can result in severe health problems like heart disease, obesity, and infertility.

What are the signs and symptoms of hypothyroidism?

The symptoms of hypothyroidism vary depending on the severity of the hormone shortage.

Signs of hypothyroidism include:

● Difficulty tolerating cold

● Fatigue

● Dry skin

● Depression

● Heavy menstrual periods or fertility problems

● Weight gain

● Thinning hair

● Slowed heart rate

● Joint and muscle pain

Hypothyroidism in infants

While hypothyroidism is more common in middle-aged and older women, anyone can develop the disease, including babies.

Babies born with thyroid deficiency may display:

  • Excessive sleepiness

  • Constipation

  • Impoverished muscle tone

As the illness develops, babies may have difficulties feeding, hindering their normal growth and development.

Infants can suffer from the following conditions due to hypothyroidism:

  • An umbilical hernia

  • A large, protruding tongue

  • Feeding difficulties

  • Whites of the eyes and yellow skin if the infants' livers cannot metabolize the bilirubin formed when the body destroys red blood cells.

  • Hoarse crying

Hypothyroidism in teens and young adults 

Generally, teens diagnosed with hypothyroidism display similar symptoms to adults, but there are additional signs, such as:

● Tiredness

● Constipation

● Feeling cold 

● Dry skin

● Delayed puberty

● Irregular menstrual periods

● Hindered or slowed growth

What causes hypothyroidism?

Hypothyroidism may be caused by several factors such as:

  • Hashimoto’s disease: This occurs when your body’s immune system produces antibodies that attack your body tissue. Excessive production of antibodies hinders the thyroid's capability to produce hormones, resulting in an underactive thyroid. Your genes and some environmental factors can cause this condition.

  • Thyroid surgery: Removal of all or part of your thyroid gland can halt or reduce hormone production. If that happens, you will need to take thyroid hormone replacement medication for life.

  • Over-reaction to hyperthyroidism medication: People with hyperthyroidism are usually treated with anti-thyroid drugs, which can lead to excessive reduction of thyroid hormone, resulting in hypothyroidism

  • Radiation therapy: This type of cancer treatment of the head and neck can affect the thyroid gland's ability to produce the thyroid hormone, resulting in hypothyroidism

  • Certain medication: Medications like lithium² used to treat psychiatric conditions can lead to hypothyroidism

There are other, less frequent, causes of hypothyroidism, including:

  • Iodine deficiency: Iodine, mainly found in seafood or plants grown in iodine-rich soil, is vital for producing thyroid hormones. Inadequate iodine can result in hypothyroidism.

  • Congenital illness: Some infants are born with thyroid deficiency, while in others, the thyroid gland may stop functioning for unknown reasons

  • Pregnancy: Women can develop hypothyroidism during or after pregnancy because they tend to produce antibodies that can attack their thyroid gland

  • Pituitary disorder: Although it is a rare cause, failure of the pituitary gland to produce adequate thyroid-stimulating hormone (TSH) can lead to hypothyroidism

Hypothyroidism versus hyperthyroidism

Hypothyroidism and hyperthyroidism are opposite conditions. Hyperthyroidism occurs due to excessive thyroid hormone production; hypothyroidism develops due to a shortage.

Some symptoms of one disease are often the reverse of the other. For instance, while hypothyroidism results in a lower metabolism rate, weight gain, and fatigue, a person with hyperthyroidism is likely to experience heightened metabolism and weight loss.

Hypothyroidism is much more common, affecting 5% of Americans aged 12 and above,¹ while hyperthyroidism only has a prevalence rate of 1.3 %³ in the same demographic. Hypothyroidism is easier to treat than hyperthyroidism by using thyroid hormone medicine, and it results in fewer long-term health issues. 

What is Hashimoto's thyroiditis?

Hashimoto's thyroiditis, also known as chronic lymphocytic or autoimmune thyroiditis, is an autoimmune disease that affects the thyroid gland. An autoimmune disease occurs when the immune system attacks the body tissues instead of ‘foreign’ substances.

In Hashimoto's disorder, the immune system produces a large number of white blood cells that accumulate in the thyroid gland. This causes damage and hinders the gland’s ability to produce hormones, leading to hypothyroidism.

Hashimoto's thyroiditis is common among middle-aged women, but anyone can develop the condition. The treatment for Hashimoto's disease is thyroid hormone replacement.

What are the signs and symptoms of Hashimoto's disease?

Hashimoto’s disease progresses steadily. You are likely to exhibit the following signs and symptoms if you are living with the condition:

Dry skin

● Increased sensitivity to cold

● Constipation

● Muscle aches

● Brittle nails

● Ataxia

● Slowed speech

Joint pain

● Depression


Puffy face

● Irregular menstrual bleeding

● Swelling of the thyroid

● Enlargement of the tongue

● Brittle nails

What causes Hashimoto's disease?

Hashimoto’s disease occurs when the immune system uses antibodies to attack the thyroid cells.

While health experts are still not sure exactly what causes Hashimoto's disease, they associate the following factors with the condition:

  • Genetic components

  • Environmental elements like infections or exposure to radiation and depression

  • Interaction between genetic and environmental elements

Risk factors related to Hashimoto's disease

These are the risk factors for Hashimoto's disease:

  • Sex: Women have a higher risk of getting Hashimoto's disease than men

  • Radiation exposure: People exposed to excess environmental radiation are at increased risk of developing the condition

  • Genetic and family health background: If one of your family members has a thyroid disorder, you have a greater risk of getting the disease

  • Other autoimmune disorders: Autoimmune diseases like rheumatoid arthritis or lupus increase your risk of Hashimoto’s disease

  • Pregnancy: This leads to changes in the immune system, which may increase the risk of getting Hashimoto’s disease

Complications related to Hashimoto's disease

Failure to treat hypothyroidism and Hashimoto’s disease can lead to:

  • Goiter: Enlargement of the thyroid gland, creating a feeling of fullness in your throat

  • Mental health problems: Depression may occur early in the condition and may become more serious in the long run

  • Pregnancy complications: Increased risk of miscarriage⁴ and higher risk of autism and other developmental diseases for the baby.

  • Heart problems: Impaired heart performance like an irregular heartbeat. It can also lead to high levels of low-density lipoprotein (LDL) cholesterol, increasing the risk of cardiovascular illness and heart failure.

What is the connection between Hashimoto's disease and hypothyroidism?

People with Hashimoto's disease may develop hypothyroidism, although this is not always the case. While Hashimoto's disease comes before hypothyroidism in certain instances, you can have Hashimoto’s disease without having hypothyroidism. 

You can also be diagnosed with hypothyroidism without testing positive for Hashimoto's thyroiditis. Therefore, while Hashimoto’s disease can lead to hypothyroidism, it is not the only cause.

Why is Hashimoto's disease sometimes misdiagnosed?

The disease is commonly misdiagnosed because the signs and symptoms are non-specific and can be easily mistaken for other health issues like hypothyroidism or hyperthyroidism. Hashimoto’s disease may exhibit vague symptoms in its earlier phases because it develops gradually.

As thyroid hormone production reduces, your body's metabolism does too, leading to symptoms like fatigue, depression, and weakness, which are common symptoms for hypothyroidism, Hashimoto's disease, and a range of other medical conditions. 

When to see a doctor

You should visit your doctor if you are regularly exhausted or have any signs and symptoms related to Hashimoto's disease or hypothyroidism like dry skin, constipation, and others listed above.

You can also schedule hormone therapy for hypothyroidism with your doctor to monitor your health. Check that you are prescribed the correct medication since some treatments can lead to the development of hypothyroidism.

The lowdown

Hypothyroidism is a common health condition where the thyroid gland fails to produce adequate vital hormones. Hashimoto's disease is an autoimmune disorder that can result in hypothyroidism.

The conditions can be mistaken for each other due to the similarity of the symptoms. Knowing the difference between hypothyroidism and Hashimoto's disease in terms of causes and symptoms is important to ensure that you get the correct treatment.

  1. Hypothyroidism (Underactive thyroid) | (NIDDK) National Institute of Diabetes and Digestive and Kidney Diseases

  2. Thyroid functions and bipolar affective disorder (2011)

  3. Hyperthyroidism (2016)

  4. Thyroid disease & pregnancy | (NIDDK) National Institute of Diabetes and Digestive and Kidney Diseases

Other sources:

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