Keto Diet Benefits For Hypothyroidism: Does It Work?

The ketogenic diet is a low-carb, high-fat diet that puts the body into a metabolic state called ketosis. This diet was initially developed to treat epilepsy, but it has since been used to manage weight and treat other chronic illnesses, including diabetes, Alzheimer's, Parkinson's, and cancer.

The keto diet is popular among people with hypothyroidism, a condition where the thyroid gland does not produce enough thyroid hormone. Thyroid hormones play a significant role in glucose metabolism, and the keto diet's low-carb nature can impair the liver's ability to convert the inactive thyroid hormone thyroxine (T4) to the active form triiodothyronine (T3).

There is a theory that the keto diet slows the conversion of T4 to T3, which could reduce metabolic activity. Research has shown that the keto diet can lead to a decrease in thyroid function and an increase in cortisol, which can further decrease thyroid function.

While the keto diet offers many benefits, it may not be suitable for everyone with hypothyroidism. It is important to consult a doctor and monitor thyroid levels closely when considering this diet. Some modifications, such as combining it with an anti-inflammatory diet, may be necessary to reduce potential negative effects.

Carbs are needed to make thyroid hormones work

Carbohydrates are the body's preferred energy source, and they are essential for a healthy thyroid and better metabolism. Carbohydrates are broken down into individual sugar molecules, which cells use as their primary energy source. Without this energy source, cells have a hard time functioning.

The thyroid makes two types of thyroid hormones: the inactive T4 (thyroxine) and the active hormone, T3 (triiodothyronine). Most of the thyroid hormone secreted is T4, which needs to be converted into T3, the active form. This conversion requires a specific enzyme called 5'-deiodinase. Low-carb diets can reduce the activity of this enzyme, resulting in low levels of T3 production.

When carb intake is drastically reduced, the conversion of T3 from T4 declines. T3 is the active thyroid hormone, and the body needs steady blood glucose levels to have readily available tools for the thyroid to function properly.

Thyroid Stimulating Hormone (TSH) is a glycoprotein. To make the proper thyroid hormones, the body needs glucose. Without adequate carbohydrates, the body cannot make the proper amount of hormones or will be unable to make them at all.

In summary, carbohydrates are an essential energy source for all cells, including thyroid cells. Not eating enough carbohydrates impacts thyroid hormone production, conversion, and regulation. Thus, low-carb diets may disrupt thyroid function.

Keto puts you in fight or flight, which is bad news for your thyroid

The ketogenic (or "keto") diet is a low-carb, high-fat diet. It triggers the body's natural metabolic process known as "ketosis". In this state, the body uses stored fat as fuel instead of glucose, its natural fuel source. The keto diet reduces inflammation and modulates the immune response, particularly when it comes to the thyroid.

However, ketosis can put your body into a state of fight or flight, increasing chemicals such as adrenaline and cortisol. These chemicals can lower thyroid function. This is bad news for people with hypothyroidism, as thyroid hormones play a significant role in glucose metabolism.

Adrenal Fatigue and Ketosis

Chronic stress can provoke hypothyroidism. When you experience stress, your body enters into the fight-or-flight mode, where it believes that you need a surge of energy in order to survive. Cortisol is the hormone that provides you with that burst of energy. Over time, high levels of cortisol can lead to insulin resistance, weaken your immune system, and cause muscle wasting if not properly addressed.

Reducing your carb intake on a keto diet has the potential to increase your cortisol levels. When your adrenals are working in overdrive to produce enough cortisol, your immune system is weakened, which can lead to signs of adrenal fatigue and even autoimmunity.

Tips for Hypothyroidism

• Combine an anti-inflammatory diet with a keto diet. Leafy green vegetables are great for reducing inflammation and assisting the body in becoming more alkaline.
• Identify dietary triggers. The most common culprits are gluten, dairy, soy, eggs, corn, nuts, shellfish, and preservatives.
• Increase water consumption. Aim for half of your body weight (pounds) in ounces of water every day.
• Improve stress management. Studies suggest that elevated levels of thyroid-stimulating hormone are associated with high levels of cortisol. Cortisol, along with other stress hormones glucagon and adrenaline, work together to increase blood sugar levels. High blood sugar levels may interfere with entering a state of ketosis.
• Reduce environmental toxins. Conventional produce is often sprayed with pesticides and herbicides that may affect your hormone balance.

Micronutrient deficiencies

The keto diet can lead to sub-optimal levels of many micronutrients, and the potential for micronutrient deficiency is significant. This is because the keto diet restricts foods like fruits, vegetables, grains, and legumes, which are rich sources of micronutrients.

A study comparing the micronutrient content of varying ratios of ketogenic diets to the Institute of Medicine's Dietary Reference Intakes (DRI) standards found that higher-fat diets were associated with lower micronutrient density.

Specific Micronutrient Deficiencies

• Vitamins B1, B5, B7, B9, D, and E: Thiamin (B1), Folate (B9), and Pantothenic Acid (B5) deficiencies can lead to serious health problems, including beriberi, Wernicke-Korsakoff syndrome, and megaloblastic anemia. Biotin (B7) deficiency can cause hair loss, dermatitis, and neuromuscular problems.
• Calcium, Magnesium, Manganese, Potassium, Sodium, Selenium, Zinc, Chromium, Copper, Iodine, Molybdenum, and Iron: Calcium deficiency can cause neuromuscular and cardiovascular issues, including tetany, rickets, and osteoporosis. Micronutrients like zinc, iron, and iodine are essential for thyroid function.

Preventing Micronutrient Deficiencies on the Keto Diet

To prevent micronutrient deficiencies on the keto diet, it is recommended to focus on specific vitamin-rich foods or take supplements.

Micronutrient-Rich Foods

• Vitamin B1: Salmon, liver, beef, mussels, nutritional yeast, pork, and trout.
• Vitamin B5: Salmon, liver, eggs, chicken, turkey, and sunflower seeds.
• Vitamin B9: Liver, asparagus, okra, spinach, collard greens, turnip greens, and broccoli.
• Vitamin B7: Beef liver, eggs, and salmon.
• Vitamin D: Cod liver oil, swordfish, salmon, tuna, yogurt, sardines, liver, egg yolk, and cheese.
• Vitamin E: Wheat germ oil, dry roasted sunflower seeds, dry roasted almonds, sunflower oil, safflower oil, hazelnuts, peanut butter, spinach, and broccoli.

It's unsustainable

The keto diet is unsustainable for people with hypothyroidism.

First, it is important to understand how the thyroid works. The thyroid gland produces two types of thyroid hormones: T3 and T4. T3 is the active and functional form of thyroid hormone, while T4 is inactive and non-functional. The body has to convert T4 to T3 in the liver, kidneys, brain, and gut through a process called deiodination. This conversion of T4 to T3 is crucial for thyroid function, and it is here that the keto diet can cause issues for people with hypothyroidism.

The keto diet is a low-carb, high-fat, moderate-protein diet. The reduction in carbohydrates puts the body in a metabolic state called ketosis, where the liver produces ketones from fat to be used as fuel. While this can aid weight loss, it can also slow the conversion of T4 to T3. Research has shown that a low-carb diet can decrease thyroid function and increase cortisol, a stress hormone. High cortisol levels can further decrease thyroid function and increase the risk of diabetes and heart disease.

Additionally, the keto diet can be challenging to maintain due to its restrictive nature. It requires a significant reduction in carbohydrate intake, which can lead to micronutrient deficiencies, particularly of potassium and vitamin C. These deficiencies can further impact thyroid function and overall health.

Furthermore, the weight loss achieved through the keto diet may not be sustainable. Most people who attempt weight loss gain back the weight they lose, and sometimes even more.

For these reasons, the keto diet may not be a sustainable or healthy option for people with hypothyroidism. It is essential to work with a healthcare professional to determine the best dietary approach for managing hypothyroidism.

Hypothyroidism and keto may cause an increase in cortisol

The keto diet is a low-carb, high-fat diet that triggers the body's natural metabolic process, ketosis. This metabolic state is characterised by elevated levels of ketones in the body. When there is insufficient insulin in the body to turn sugar into energy, the liver produces ketones from fat. These ketones then serve as a fuel source for the body and brain.

However, the keto diet may not be suitable for people with hypothyroidism. Thyroid hormones play a significant role in glucose metabolism. Therefore, while it is generally advisable to cut down on carbs, too little insulin can impair the liver's ability to convert the inactive thyroid hormone thyroxine (T4) to the active form, triiodothyronine (T3).

Additionally, when the body remains in ketosis for too long, accumulated acidity can lead to inflammation. Many people with hypothyroidism already struggle with chronic inflammation, and an overly acidic diet may exacerbate this issue.

Furthermore, the keto diet may put a strain on the adrenal glands, which produce stress hormones such as cortisol. Reduced carb intake can lead to decreased thyroid hormone levels and increased cortisol levels, which can further decrease thyroid function. This can result in a vicious cycle where high cortisol levels cause a sluggish thyroid and increased TSH (Thyroid Stimulating Hormone) levels.

Cortisol also slows down the conversion of T4 to T3 by directly impacting deiodinase activity and increasing reverse T3, an inactive form of T3. As a result, people with hypothyroidism who follow a keto diet may be at an even greater risk for high cortisol levels, which can increase the risk for diabetes and heart disease.

Therefore, it is important for people with hypothyroidism to proceed with caution when considering the keto diet. It is recommended to address stress levels and work with a knowledgeable care team to create a personalised meal plan that takes into account individual sensitivities and health conditions.

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