Diabetes and thyroid disorders occur due to hormonal changes. Although growing evidence suggests a link between diabetes and thyroid disorders, researchers are currently unsure what connects them.

Thyroid disorders and diabetes are two of the most common conditions that endocrinologists treat. An “endocrine disorder” is any condition that affects the production and release of hormones.

People living with diabetes may be at a higher risk of developing a thyroid disorder and vice versa.

This article will discuss the relationship between diabetes and thyroid disorders in more detail.

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Experts refer to both diabetes and thyroid disorders as endocrine disorders.

This term refers to medical conditions in which the endocrine system, which produces hormones, cannot function correctly. These conditions can have several potential causes, and because they affect hormones, they can lead to a wide range of symptoms.

The endocrine system consists of eight major glands throughout the body, including the thyroid and pancreas.

Thyroid disorders

The thyroid is a butterfly-shaped gland that sits at the front of the neck. It produces hormones, such as thyroxine (T4) and triiodothyronine (T3), which help regulate body processes. These processes include the following:

In some cases, the thyroid may overproduce hormones, causing a condition called hyperthyroidism.

It can also underproduce hormones, leading to a condition called hypothyroidism.

Autoimmune conditions can often result in the development of these thyroid disorders. Hashimoto’s thyroiditis and Graves’ disease are common causes of hypothyroidism and hyperthyroidism, respectively.


The pancreas is a gland in the abdomen that plays a role in the digestive system. It produces insulin, a hormone that helps blood sugar, also called glucose, enter cells, providing the cells and body with essential energy. Without enough insulin, a person may develop diabetes.

Diabetes affects the body’s ability to process blood glucose. There are multiple types of diabetes, with type 1 and type 2 being the most common.

In type 1 diabetes, the immune system mistakenly attacks the pancreas, reducing insulin production.

Many variables may contribute to the development of type 2 diabetes, such as:

The thyroid secretes hormones that regulate a person’s metabolism. An imbalance in these hormones can affect blood sugar in several ways.

Excess thyroid hormone increases a metabolic process called lipolysis, which involves the breakdown of body fat into serum-free fatty acids, and the secretion of insulin and glucagon. The sum of these effects causes glucose metabolism to worsen, which can cause glucose intolerance and diabetes.

Glucagon is a hormone that the pancreas releases when a person experiences hypoglycemia, a condition in which their blood sugar levels are too low. The body stops releasing glucagon when the blood sugar levels return to a healthy range.

According to a 2016 review, an excess of glucagon is the key factor in the development of diabetes.

Ivan’s story: Living with diabetes and a thyroid disorder

“Living with diabetes and a thyroid disorder has been tough, but I manage them carefully with support. For diabetes, I watch my diet, check my blood sugar, and stay active. I also take medication and see my endocrinologist regularly for my thyroid.

It’s intriguing how diabetes and thyroid problems are linked. They both involve the endocrine system. People with diabetes often have thyroid issues, and vice versa. So, I closely monitor both conditions and ensure my doctors know my full medical history.

Managing both conditions means living a healthy lifestyle and getting specialized care. Following my treatment plan helps me stay healthier and improves my quality of life.”

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Evidence suggests a link between insulin resistance and both hyperthyroidism and hypothyroidism. Because thyroid hormones are essential for carbohydrate metabolism, thyroid dysfunction can affect insulin and lead to the development of type 2 diabetes.

Insulin resistance may occur due to hyperthyroidism because of an increase in fatty free acids in the bloodstream. In body fat, the thyroid hormone stimulates lipolysis, the breakdown of body fat into fatty acids.

Research suggests there is a link between the levels of serum-free fatty acids and diabetes because these fatty acids can hinder insulin secretion and cause insulin resistance.

A 2017 review found a link between insulin resistance and even small increases in the thyroid-stimulating hormone (TSH), which tends to be high in hypothyroidism. Research suggests the association between hypothyroidism and insulin resistance may be partially due to insulin’s decreased ability to increase glucose utilization in muscle tissue.

Because hypothyroidism can slow the metabolism, insulin stays in the bloodstream longer. This suggests a person with diabetes and hypothyroidism may require a lower dose of insulin for their treatment.

Some forms of thyroid disorders are autoimmune conditions. Research suggests a close association between the autoimmune response that causes type 1 diabetes and autoimmune-induced thyroid dysfunction (AITD).

An estimated 17–30% of adults with type 1 diabetes also have AITD. Additionally, 25% of children with type 1 diabetes have autoimmune hypothyroidism. Research suggests that genetic factors may contribute to this.

The hypothalamic-pituitary-adrenal (HPA) axis, which is the interaction of the hypothalamus, pituitary gland, and adrenal glands, may be another possible link between diabetes and the thyroid.

These glands secrete hormones into the blood and help manage reactions to stress by regulating levels of the hormone cortisol. Too much cortisol can increase a person’s glucose levels by stimulating the liver to increase new glucose formation, causing a state of insulin resistance and a decrease in insulin secretion.

As such, problems with the HPA axis can lead to atypical blood sugar levels and affect the body’s response to insulin.

In many cases, it may not be possible to prevent diabetes or thyroid disorders.

At present, there is no guaranteed way to prevent an autoimmune disease from developing. However, a person may be able to prevent or delay the onset of conditions that do not have genetic causes.

Preventing and managing diabetes

The Centers for Disease Control and Prevention suggests it is possible to prevent type 2 diabetes by eating a healthy diet, exercising regularly, and losing excess weight if needed.

To help manage diabetes, a person can create a diabetes self-care plan, which may include:

Treating and managing thyroid disorders

Treatment for thyroid disorders will depend on whether the thyroid gland is underactive or overactive.

While there is currently no cure for hypothyroidism, a person can manage it with medication. By taking T4 replacements, a person can increase their T4 and return their TSH to a healthy level.

Some treatment options are available to help manage hyperthyroidism, including:


A doctor may also advise individuals currently living with either diabetes or a thyroid disorder to receive regular screenings for the other condition. For example, some evidence suggests it may be beneficial to offer screening for a thyroid disorder to people living with type 1 or type 2 diabetes.

Anyone who suspects they might have diabetes or a thyroid dysfunction should contact a doctor to receive a diagnosis and treatment if needed.

Common symptoms of diabetes include:

Symptoms of hypothyroidism can include having dry skin and feeling cold and tired.

With hyperthyroidism, a person may experience the following:

It is also best for people to contact a doctor if they are already living with either diabetes or a thyroid disorder and suspect they might also have the other condition.

Data from a 2020 study on the relationship between diabetes and thyroid dysfunction suggests it is best for people with any type of diabetes to receive routine tests for thyroid dysfunction.

Diabetes resources

Visit our dedicated hub for more research-backed information and in-depth resources on diabetes.

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Evidence suggests a close link between thyroid disorders and diabetes. Thyroid dysfunction can affect a person’s insulin and blood sugar levels, which can contribute to the development of diabetes.

Both underactive and overactive thyroid disorders are more common in people who have diabetes than those who do not have diabetes. It is best for a person who is concerned about either condition to contact a doctor.