Keto And Thyroid: Is There A Link To Dysfunction?

The ketogenic diet is a low-carb, moderate protein, and high-fat diet. It is often used to achieve health goals such as weight loss. However, the keto diet is not for everyone and can have a detrimental impact on hormone balance, particularly thyroid hormones.

Thyroid hormones play a significant role in metabolism. The thyroid gland produces two hormones: T4, the inactive form, and T3, the active form. T3 plays a role in the metabolism of all cells and manages functions such as the speed of digestion.

Research suggests that the keto diet can lower T3 levels, leading to weight gain. This is because the body lowers T3 production when it senses caloric/carbohydrate restriction, reducing energy expenditure to conserve energy. Additionally, weight loss, a common occurrence on the keto diet, reduces the conversion of T4 to active T3.

Furthermore, the keto diet can put the body in a state of chronic inflammation, which may be detrimental for people with hypothyroidism. The diet can also increase stress hormones such as cortisol, which can further impair thyroid function.

However, there is no one-size-fits-all approach to dieting, and the keto diet may offer benefits for some individuals. For example, the keto diet can be beneficial for people with epilepsy, and it has been shown to improve blood sugar control and lipid panels.

To mitigate potential negative effects on thyroid function, it is important to ensure adequate calorie intake, reduce consumption of inflammatory foods, increase water intake, and improve stress management.

Carbs are needed to make thyroid hormones work

The thyroid gland, which sits at the base of your neck, makes different kinds of thyroid hormones. One kind, T3, is active and is the functional form of thyroid hormone. The other kind, T4, is inactive and non-functional. The body has to convert T4 to T3 for it to be useful. This conversion requires a specific enzyme called 5'-deiodinase.

Research shows that:

• Carbohydrates are important for the conversion of T4 to T3, and they directly impact the levels of T3 in your body.
• Carbohydrates in your diet directly impact how much of T4 gets converted to T3.
• Low-carb diets can reduce the activity of the enzyme 5'-deiodinase, resulting in low levels of T3 production.
• Carbohydrates trigger the release of insulin, a hormone that regulates blood sugar levels by moving sugar into your cells.
• If your body does not get enough carbs over time, this can impact how your cells respond to insulin, known as insulin sensitivity. A decrease in insulin sensitivity means your cells can’t move sugar into your cells, thus impacting how they function. In the case of your thyroid, the outcome would be a lack of thyroid hormone production.
• Low-carb diets mimic a fasting state, causing your body to rely on other macronutrients for energy. Evidence shows that during a state of fasting, your T3 levels decrease.

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

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

The keto diet is a low-carb, high-fat diet that puts your body in a metabolic state called ketosis. This means your body burns fat for fuel instead of glucose from carbs. While this can be beneficial for weight loss, it can also be a major strain on the adrenals, which produce the stress hormone cortisol.

When we don't consume enough carbs, the body has to figure out how to make carbs to sustain blood sugar. It does this by relying on stress hormones, namely cortisol and adrenaline. Cortisol is responsible for increasing gluconeogenesis in the liver, which is the process of making carbs from protein and fat.

Research shows that people with hypothyroidism tend to have higher levels of stress hormones to begin with. So, when you're on a keto diet, your cortisol levels can go even higher. Cortisol raises Thyroid Stimulating Hormone (TSH), which corresponds with a sluggish thyroid, or hypothyroidism. Cortisol also slows the conversion of T4 (inactive thyroid hormone) to T3 (active thyroid hormone) by directly impacting deiodinase activity and increases reverse T3 – an inactive form of T3 that can no longer be used by the body.

A keto diet could put people with hypothyroidism at an even greater risk for high cortisol levels, which can then increase their risk for diabetes and heart disease.

Micronutrient deficiencies

The keto diet restricts carbohydrates to between 5 and 10% of dietary calories, which means that many micronutrient-rich foods like fruits, vegetables, grains, and legumes are limited or eliminated. This can lead to deficiencies in several essential vitamins and minerals. Research has shown that the keto diet provides sub-optimal levels of many micronutrients, and the potential for deficiency is significant.

One study found that a 3-day keto diet that selected nutrient-dense foods was still deficient in 19 out of 24 micronutrients evaluated, with 11 nutrients provided at less than 50% of the recommended intake. These included thiamin, folate, pantothenic acid, calcium, copper, iron, magnesium, manganese, molybdenum, selenium, and zinc.

Another study evaluated the micronutrient content of different ratios of ketogenic diets and found an association between higher-fat diets and lower micronutrient density. This study also suggested that the average vitamin and mineral deficiency on a ketogenic diet could be as high as 56%.

Some specific micronutrient deficiencies that have been identified on the keto diet include:

• Vitamin B1 (Thiamin): Found in salmon, liver, beef, mussels, nutritional yeast, pork, and trout.
• Vitamin B5 (Pantothenic Acid): Found in salmon, liver, eggs, chicken, turkey, trout, and sunflower seeds.
• Vitamin B9 (Folate): Found in liver, asparagus, okra, spinach, collard greens, turnip greens, and broccoli.
• Vitamin B7 (Biotin): Found in beef liver, eggs, and salmon.
• Vitamin D: Found in cod liver oil, swordfish, salmon, tuna, yogurt, sardines, liver, egg yolk, and cheese.
• Vitamin E: Found in wheat germ oil, dry roasted sunflower seeds, dry roasted almonds, sunflower oil, safflower oil, hazelnuts, peanut butter, spinach, and broccoli.

In addition to these specific deficiencies, the keto diet may also lead to deficiencies in other vitamins and minerals, such as vitamin B2, B3, B6, B12, C, K, calcium, magnesium, manganese, potassium, sodium, selenium, and zinc.

To avoid micronutrient deficiencies on the keto diet, it is recommended to focus on specific vitamin-rich foods or consider supplementation. However, it is important to note that supplementation should not replace a well-balanced diet and should be done under the guidance of a healthcare professional.

The keto diet is unsustainable

The keto diet is a high-fat, moderate-protein, low-carbohydrate eating pattern. It is different from other low-carb diets, which tend to focus on protein. The keto diet is designed to help people burn fat by reducing the body's supply of glucose, which is the primary source of energy for all cells in the body. While the keto diet can lead to initial weight loss, it is not a sustainable or healthy method, especially for people with hypothyroidism.

Micronutrient Deficiencies

Firstly, the keto diet can lead to micronutrient deficiencies. Carbohydrate-rich foods such as grains, lentils, fruits, and vegetables are rich sources of vitamins and minerals. Restricting these foods can put people at risk of vitamin and mineral deficiencies, including potassium and vitamin C.

Unbalanced Diet

Secondly, the keto diet is an unbalanced diet that requires excessive willpower. It is not designed to be followed long-term, and the weight loss is likely to be regained.

Health Risks

Thirdly, the keto diet poses several health risks. It is high in saturated fat, which is linked to heart disease. It can also lead to nutrient deficiencies, liver problems, kidney problems, constipation, fuzzy thinking, and mood swings.

Stress and Inflammation

Finally, the keto diet can increase stress and inflammation in the body. When the body doesn't consume enough carbohydrates, it relies on stress hormones like cortisol and adrenaline to sustain blood sugar. This can lead to higher cortisol levels, which can increase the risk of diabetes and heart disease.

In conclusion, while the keto diet may be attractive for quick weight loss, it is not a sustainable or healthy option, especially for people with hypothyroidism. It is important to work with a registered dietitian to find a balanced and enjoyable eating plan that includes carbohydrates.

Calorie restriction lowers thyroid hormone

Calorie restriction has been shown to lower thyroid hormone levels. This effect is likely due to the calorie restriction itself, rather than a decrease in body fat mass.

The role of thyroid hormones

Thyroid hormones play a significant role in metabolism, and thyroid hormone status correlates directly with body mass and energy expenditure. The thyroid gland produces thyroxine (T4), the inactive form of the thyroid hormone, and triiodothyronine (T3), the active form. The body has to convert T4 to T3 for it to be functional. This conversion happens in the liver, kidneys, brain, and gut through a process called deiodination.

The impact of calorie restriction on thyroid function

Carbohydrates are important for deiodination and directly impact T3 levels. Calorie restriction can lead to decreased T3 levels, which can impair the liver's ability to convert T4 to T3. Additionally, when the body remains in ketosis for too long, accumulated acidity can lead to inflammation, which may worsen existing chronic inflammation in people with hypothyroidism.

The effects of calorie restriction on the body

Calorie restriction can also impact the body in other ways. It can increase stress hormones like cortisol, which can interfere with thyroid function and increase the risk of diabetes and heart disease. Calorie restriction may also lead to micronutrient deficiencies, particularly of potassium and vitamin C, which are essential for thyroid health.

Modifying the keto diet for hypothyroidism

While the keto diet may not be suitable for everyone with hypothyroidism, some modifications can make it more manageable. Combining an anti-inflammatory diet with keto can help reduce inflammation. Increasing leafy green vegetables, Omega-3 fatty acids, and vitamin D can also help. Identifying dietary triggers, such as gluten, dairy, soy, and nuts, can help reduce inflammation and improve thyroid function. Additionally, increasing water consumption, improving stress management, reducing environmental toxins, and considering intermittent fasting may offer some health benefits.

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