Should You Try a Keto Diet if You Have Hypothyroidism?
The ketogenic (or “keto”) diet is a low-carb diet emphasizing high-fat intake and largely limiting carbohydrates. Historically, the keto diet was developed as an alternative treatment for epileptic children and has been proven to reduce the number of seizures in patients with epilepsy.1 It also shows promise for use in treating other chronic illnesses, including diabetes, Alzheimer’s, Parkinson’s, and cancer.2 Given its potential health benefits, you may be wondering if you should try a keto diet if you have hypothyroidism. Here’s what I recommend.
The Keto Diet and Hypothyroidism
What is Hypothyroidism?
Hypothyroidism, or having an underactive thyroid, is when your thyroid gland does not produce enough thyroid hormone. Thyroid hormones affect nearly every part of your body, including your metabolism, brain, heart, muscles, and skin. Without enough thyroid hormone, all of your bodily processes slow down to a sluggish crawl. Research shows that women and those with autoimmune disease are more likely to develop hypothyroidism.3
The Role Your Adrenals Play
Chronic stress can also provoke hypothyroidism. Your adrenals produce stress hormones, such as cortisol. When you experience stress, a cascade of stress hormones signals your body to slow down all processes that are unnecessary for overcoming the stressor in front of you, including thyroid hormone production.
In our modern society, many of us experience one stressor after another with no time in between to physically recover. Chronic stress overworks your adrenals, which are unable to keep up with the constant demand for more and more stress hormones, inevitably leaving you in a state of adrenal fatigue. This flooding and eventual plummeting of stress hormones cause your thyroid activity to come to a screeching halt.
Adrenal Fatigue and Ketosis
The goal of a keto diet is to achieve the metabolic state known as “ketosis.” Depriving your body of its main fuel source, glucose (which comes from carbs), triggers your body to burn stored fat for fuel instead. It’s this fat-burning state of ketosis that is responsible for the rapid weight loss and enhanced energy and brain function people typically experience on a keto diet.
However, ketosis can be a major strain on the adrenals. Reduced carb intake leads to a decrease in thyroid hormone levels and an increase in cortisol—which decreases thyroid function further and means more work for your adrenals.4 If your adrenals are already fatigued, you do not want to stress them even more by going into ketosis.
This vicious cycle is why you should proceed with caution when it comes to a keto diet if you are hypothyroid, particularly if adrenal fatigue is one of the primary triggers of your hypothyroidism. For this reason, I would recommend avoiding a keto diet until you have addressed your stress levels.
How to Determine if a Keto Diet is Right for You
Everybody is different, so it’s important to listen to your body and know what you do or do not tolerate. You may do perfectly fine on a keto diet, or you might find your body doesn’t respond well to it. Either way, if you have hypothyroidism and are looking to experiment with a keto diet, be sure to consult your doctor first and monitor your thyroid levels closely during this time.
To learn more about whether a keto diet might be right for you, including the health benefits of a keto diet, how to follow a keto diet, and which supplements you can take to help support you while following a keto diet, see my article Should You Try a Keto Diet if You Have an Autoimmune Disease?