It’s not uncommon for someone to have both diabetes and a thyroid disease. In fact, having diabetes or metabolic syndrome, increases your risk of developing a thyroid disease—and vice versa (1). 

Up to 20 million Americans have a thyroid condition, and the go-to remedy is prescription medication or synthetic hormone replacement that must be maintained for life. Scientists, doctors, and researchers have recently connected the dots between thyroid conditions and low blood sugar. In this article, we share the relationship between thyroid and blood sugar levels, how your blood sugar affects your thyroid and natural ways to support healthy blood sugar levels and thyroid function. 

The Connection Between Our Liver & Thyroid 

Did you know that 80 percent of the thyroid hormone (T4) gets converted to T3 in the liver? These hormones play a massive role in weight, mood, metabolism, and body temperature. That means healthy liver function is essential for a healthy thyroid. So, where does blood sugar come in?

The liver acts as our body’s glucose (or fuel) reservoir—and it needs both glucose (sugar) and amino acids (protein) to function correctly. When blood sugar drops, the liver either makes more glucose or turns to its stored glycogen supply, turns it into blood glucose, and releases it into the bloodstream. But here’s the thing, when the liver has to do this on top of its HUNDREDS of other jobs, important tasks get put on the back-burner—like thyroid hormone conversion. 

When/Why Our Blood Sugar Drops 

Having low blood sugar means that there is not enough circulating blood sugar, starving yourself making them unable to function correctly. Hypoglycemia, or the technical term for low blood sugar, is most common in those with diabetes but can also occur for other reasons in seemingly healthy people. For instance, maybe you haven’t eaten for a while, perhaps you’re not eating often enough, or you’re not getting in enough carbs or healthy sugars from fruits. Other causes could be certain medications, hormone or enzyme deficiencies, excess exercise, and diet. Having low blood sugar means that there is not enough circulating blood sugar, starving yourself making them unable to function correctly. 

Low blood sugar can cause both short-term and long-term complications, and you should know the signs that might warrant hypoglycemia or a thyroid condition. 

Hypoglycemia typically means blood sugar less than 60 for most people. Some people with unknown diabetes or prediabetes who have higher blood sugar all the time can experience a drop that is not necessarily normal. 

You may have low blood sugar if you experience the following:

  • Fatigue: glucose is a huge source of energy for our brains; without it, we miss the motivation and fuel for activities
  • Irritability and Anxiousness: it could come as mild as general irritability or annoyance, or it could be an intense mood swing. This is a neurogenic symptom of hypoglycemia. 
  • Constant hunger: while frequently skipping meals causes hypoglycemia, low glucose levels cause your liver to start releasing glucose to make you crave food to replace it. 
  • Headaches: throbbing headaches in the temples is a common symptom of low blood sugar. But oftentimes it comes with other hypoglycemia symptoms like dizziness, sweating, confusion, inability to concentrate, and shakiness. 

How Low Blood Sugar Affects the Thyroid 

Blood sugar imbalances are common in people with Hashimoto’s disease, also known as hypothyroidism. 

Our bodies are programmed to see low blood sugar as a threat to survival. Chronic hypoglycemia can result in seizures, coma, or even death. When blood sugar drops below normal, the adrenals secrete the stress hormone cortisol. Cortisol tells your liver to produce more glucose. The problem is, with chronic cortisol release, the body is stuck in sympathetic mode or fight or flight. Repeated cortisol release due to low blood sugar suppresses pituitary function, and without proper pituitary function, the thyroid can’t function properly. 

How Poor Thyroid Function Affects Blood Sugar 

Flip the situation around, and low thyroid function can cause dysglycemia (hyperglycemia & hypoglycemia) and metabolic syndrome. It does this a couple of ways:

  • Slows the rate of glucose uptake by cells 
  • Decreases rate of glucose absorption in the gut 
  • Slows the clearance of insulin from the blood 
  • Slows response of insulin to elevated blood sugar 

These mechanisms are associated with hypoglycemia, and when someone is hypoglycemic, their cells aren’t sensitive to glucose. 

How to Keep Your Blood Sugar in a Healthy Range 

One of the reasons we may experience low blood sugar is because we are not eating frequently enough or getting enough carbs. There is also a flip side to this. This condition, called reactive hypoglycemia, happens when the body secretes excess insulin after a high carbohydrate meal, causing blood sugar levels to drop below normal. 

Normal range of fasting blood glucose (right in the morning before you eat or drink) is 75-95 mg/dL. Measuring your fasting blood glucose levels may be a good idea to make sure you are staying in a healthy range. 

Another option is looking at postprandial blood glucose, which measures blood sugar 1-2 hours after a meal. Studies show that looking at this is the most accurate predictor of future diabetic complications. 

Normal postprandial blood sugar is around 120 mg/dL. Most normal people are under 100 mg/dL two hours post-meal. 

Support Healthy Thyroid Function 

Supporting healthy thyroid function can look like using supportive essential oils or consuming foods like seaweed, kelp, shiitake mushrooms, brazil nuts, and more. Check out our episode on Natural Support for Thyroid Issues for more information. 

Other Ways to Support Healthy Blood Sugar Levels

  • Eat within an hour of waking up 
  • Consume a meal or snack with carbs and protein every 3-4 hours (remember, carbs does not equal only bread and pasta. It also means veggies)
  • Give your liver some love with wild blueberries, and superfood greens 
  • Avoid fasts of 10 hours or more (through the night) 
  • Keep stress levels down 
  • Measure glucose levels with a blood glucose meter 


  1. Wang C. The relationship between type 2 diabetes mellitus and related thyroid diseases. J Diabetes Res. 2013;2013:390534. doi:10.1155/2013/390534

Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.