Hypothyroidism and type 2 diabetes
It’s not uncommon for someone to have both thyroid disease and diabetes. In fact, if you have type 1 diabetes, type 2 diabetes, insulin resistance, or metabolic syndrome, your risk of developing thyroid disease is increased. And thyroid disease increases your risk of developing metabolic syndrome or type 2 diabetes. This association is even stronger if you are overweight or obese.
Based on studies and research People with prediabetes and low thyroid function were more than twice as likely to progress to full-blown type 2 diabetes compared to those with normal thyroid hormone levels.
Overall, low thyroid function—even in the low-normal range—increased the risk for diabetes by 13%. But among those with prediabetes, the risk of progressing to type 2 diabetes ranged from 15% for those with normal thyroid function to 35% for those with signs of low function. Even “low normal” thyroid functioning increased risk.
According to experts, thyroid screening tests are an unavoidable necessity for people with early diabetes. On the other hand, treatment of hypothyroidism can help people with type 2 diabetes to control the course of the disease.
Diabetes
Diabetes mellitus, commonly known as diabetes, is a metabolic disease that causes high blood sugar. Blood glucose is your main source of energy and comes from the food you eat. Insulin, a hormone made by the pancreas, helps glucose from food get into your cells to be used for energy. Sometimes your body doesn’t make enough—or any—insulin or doesn’t use insulin well. Glucose then stays in your blood and doesn’t reach your cells.
Over time, having too much glucose in your blood can cause health problems. Although diabetes has no cure, you can take steps to manage your diabetes and stay healthy. Untreated high blood sugar from diabetes can damage your nerves, eyes, kidneys, and other organs. There are a few different types of diabetes:
Type 1 diabetes is an autoimmune disease. The immune system attacks and destroys cells in the pancreas, where insulin is made. It’s unclear what causes this attack. About 10 percent of people with diabetes have this type.
Type 2 diabetes occurs when your body becomes resistant to insulin, and sugar builds up in your blood.
The link between hypothyroidism and type 2 diabetes
There are many ways in which low thyroid hormone levels can increase the risk of diabetes. First of all, thyroid gland and thyroid hormones play a major role in regulating many of your body’s biological processes, such as growth, development, and metabolism.2 Because thyroid disease interferes with metabolism, it can alter your blood sugar. This increases your risk of developing diabetes, and it makes it harder to manage your blood sugar if you already have diabetes. Low thyroid hormone levels are associated with higher Body Mass Index, which in turn is a risk factor for diabetes.
Thyroid hormone is also directly involved in the control of insulin secretion and glucose homeostasis. Hypothyroidism is associated with decreased insulin sensitivity and glucose tolerance and treatment of hypothyroidism has shown to improve these effects. The exact mechanism or mechanisms that are involved in the association need to be investigated.
The link between hypothyroidism and insulin
production of thyroid hormones. But insulin also functions in the opposite way thyroid hormones do in other tissues, which increases thyroid hormone levels.4
Excess or deficient insulin can induce changes in thyroid hormone production and activity.
When metabolism is slowed in hypothyroidism, insulin may linger longer in the body, causing a greater risk of hypoglycemia (low glucose levels). Hypothyroidism has also been associated with an increased sensitivity to insulin, which can contribute to hypoglycemia.
If further research confirms a connection, in the future people with prediabetes and low or low-normal thyroid function might be more strongly encouraged to adopt healthy lifestyle changes to prevent prediabetes or even begin diabetes treatment or thyroid treatment sooner, the researchers note.
References
https://www.endocrineweb.com/news/diabetes/55372-low-thyroid-hormone-raises-risk-type-2-diabetes
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3647563/
https://www.niddk.nih.gov/health-information/diabetes/overview/what-is-diabetes
https://www.healthline.com/health/diabetes
