Type 2 diabetes risk linked to low thyroid function, new study suggests

Type 2 diabetes risk linked to low thyroid functionA low thyroid function has been found to be a risk factor for type 2 diabetes. Researcher Dr. Layal Chaker said, “Low thyroid function is associated with a higher risk of developing diabetes and also of progression from prediabetes to diabetes. Of course, we’ve always screened for thyroid disorders in patients with type 1 diabetes, because of the autoimmune association…But there’s overlap between the symptoms of hypothyroidism and type 2 diabetes.”

The study included 8,452 individuals over the age of 45 without diabetes, but with low thyroid hormone levels. After an average 7.9-year follow-up, 1,100 developed prediabetes and 798 developed type 2 diabetes. Low hormone levels were found to be a risk factor for diabetes and higher T4 hormone levels were associated with a lower risk of diabetes.


The Centers for Disease Control and Prevention (CDC) estimates that 29.1 million Americans have diabetes of which 8.1 million cases are undiagnosed. With such high numbers, diabetes prevention should really be on the forefront of health.

We currently know and understand many causes of type 2 diabetes. Being overweight, eating a poor diet, not getting enough sleep, and not exercising can all contribute to the onset of type 2 diabetes. But did you know your thyroid could also be a cause of diabetes?

The relation between thyroid disease and diabetes

Thyroid disorders affect nearly as many Americans as diabetes – about 27 million. Both diabetes and thyroid disorders affect the endocrine system – glands that secrete hormones useful for bodily functions. So it is not surprising that those with diabetes may also have a thyroid disorder, and vice versa.

In diabetes, the body has a difficult time using insulin, and since the thyroid is responsible for the metabolism, it then greatly affects the manageability of diabetes. The two are so closely related that among those with diabetes the occurrence of thyroid disorders increases by 10 percent.

Although it appears that thyroid disorders and diabetes occur simultaneously, researchers have yet to uncover the exact cause-and-effect relationship between the two.

How does thyroid disease affect blood sugar level and diabetes?

There is an apparent relationship between thyroid disease and diabetes, albeit not fully understood, so it’s important to know how exactly thyroid diseases affect diabetes.

Controlling sugar metabolism is one of the thyroid’s functions. A thyroid disorder then negatively impacts blood sugar, making diabetes more difficult to manage.

In hyperthyroidism, the thyroid is working too quickly, resulting in an increase in blood sugar produced by the liver and quicker absorption.

With hypothyroidism, the thyroid is working slower, so insulin may get cleared more slowly. Along with hypothyroidism comes higher cholesterol as well, which is again a dangerous enemy for diabetics.

Thyroid dysfunction can:

  • Slow down the cell’s ability to absorb glucose
  • Decrease the amount of glucose in the gut
  • Slow down the response of insulin when blood sugar levels spike.

Clearly then, thyroid disorders weigh heavily on diabetes.

Effect of diabetes on thyroid disease

On the other hand, if diabetes isn’t controlled, high blood sugar can negatively impact the thyroid health by destroying the thyroid gland, especially in individuals with an autoimmune thyroid disease.

But when blood sugar is low, cortisol – the stress hormone – is released, creating a hormone imbalance as well as prompting the liver to pump out more insulin. Once again, this leads to further damage to the thyroid gland.

Thyroid disease and diabetes share many common symptoms including fatigue, weight loss or weight gain, and trouble sleeping. These symptoms may become worse if the thyroid disease or diabetes is not managed properly.

Tips to manage thyroid disorders

A common theme between thyroid diseases and diabetes is management. Without proper management both illnesses can become more severe, making the health of the individual worse. Here are a few tips to help you manage your thyroid disorder more successfully.

  • Use hormone replacement medications
  • Eat an iodine- and selenium-rich diet
  • Exercise
  • Reduce stress
  • Eliminate soy and gluten from your diet.

These are just some tips that can help you better manage your thyroid disorder.

Tips to managing diabetes

On the other hand, it is just as important to manage your diabetes. Although many of the tips are similar, they are still important to note.

  • Eat a balanced diet
  • Avoid processed and fried foods
  • Exercise
  • Control your weight
  • Monitor your blood sugar numbers
  • Pay attention to the carbohydrate content in food items – they, too, contain sugar
  • Monitor your sugar intake

By following these tips, you can also have proper control of your diabetes. Pair them together with the tips to manage your thyroid disease, and you can continue to live a healthy life.

If you’re concerned about your thyroid or your diabetes, speak with your doctor. Also keep in mind that diabetes is preventable, so lowering your risk of developing diabetes can also lower your chances of developing a thyroid disorder. So if your doctor is already concerned that you may be prediabetic, start taking the appropriate measures to prevent the onset of diabetes.

Related Reading:

Hypothyroidism linked to diabetic nephropathy in type 2 diabetes, study

Hypothyroidism is linked to diabetic nephropathy in type 2 diabetes. The researchers measured serum thyroid hormone levels and urinary albumin:creatinine ratio in 414 patients with type 2 diabetes. Thirty-six of the patients had subclinical hypothyroidism (SCH), and prevalence of diabetic nephropathy was greater among those in the subclinical hypothyroidism group. Continue reading…


Hypothyroidism risk increases in chronic kidney disease patients with declining kidney function

Hypothyroidism risk increases in chronic kidney disease patients with declining kidney function. The study looked at a nationally representative cohort of 461,607 veterans with chronic kidney disease stages 3-5. The researchers found that each 10 mL/min/1.73 m2 lower estimated glomerular filtration rate (eGFR) was associated with an 18 percent increased risk of hypothyroidism in adjusted analyses. Continue reading…