Keto And Thyroid: Can This Diet Help?

The ketogenic diet is a low-carb, high-fat diet that triggers the body's natural metabolic process known as ketosis. It has gained popularity in recent years, often being touted as a magic bullet for weight loss. However, it is not for everyone, especially those with thyroid disorders or at risk of developing one. The thyroid plays a crucial role in the body's metabolism, and the keto diet has the potential to detrimentally impact hormone balance, particularly thyroid hormones.

Research indicates that periods of starvation and weight loss from the keto diet can lower T3 levels, leading to weight gain. This is because the body interprets any form of energy restriction as a sign of famine, leading it to reduce metabolism and conserve energy stores. Additionally, even when energy is not restricted, a ketogenic diet is associated with sharply reduced blood levels of active thyroid hormone.

For those with thyroid conditions, the keto diet may worsen symptoms and lead to side effects like the keto flu. It can also be challenging to regulate thyroid hormone levels, especially when starting the diet. Furthermore, ketosis can decrease the liver's ability to convert T4 (inactive thyroid hormone) to T3 (active thyroid hormone), potentially affecting thyroid function.

While the keto diet may offer benefits such as weight loss and improved energy levels, it is important to proceed with caution, especially for those with thyroid conditions or adrenal fatigue. Consulting a doctor or a registered dietitian and monitoring thyroid levels closely is essential before starting the keto diet.

Carbs are needed to make thyroid hormones work

The thyroid is a tiny gland located at the front of your neck, below your voice box. It plays a crucial role in the development of your body and the regulation of your metabolism. The thyroid secretes two hormones: T4 (tetraiodothyronine) and T3 (triiodothyronine). T4 is the inactive form, which is converted to T3 as needed. T3 is the biologically active hormone that plays a role in the metabolism of all your cells and manages essential functions such as the speed of digestion.

When you adopt a low-carbohydrate lifestyle, your thyroid hormone levels may change. This is because your body interprets any form of energy restriction as a sign of famine, leading it to reduce metabolism to conserve energy stores. Additionally, a ketogenic diet is associated with sharply reduced blood levels of active thyroid hormone, T3. This reduction in T3 has been taken as evidence that carbohydrate restriction impairs thyroid function.

Carbohydrates are important for deiodination and impact T3 levels:

Research shows that carbohydrates are crucial for the process of deiodination, which is the conversion of inactive T4 to active T3. 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.

Carbohydrates impact the conversion of T4 to T3:

Carbohydrates in your diet directly influence how much T4 is converted into T3, the functional form of thyroid hormone. Restricting carbohydrate intake can decrease your thyroid's ability to produce and secrete thyroid hormones, leading to increased tiredness and sluggishness.

Carbohydrates regulate insulin sensitivity:

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, it 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, impacting their function and resulting in a lack of thyroid hormone production.

Carbohydrates are an essential energy source:

Carbohydrates are the body's preferred energy source. They provide the cells with the fuel they need to function optimally. Without enough carbohydrates, your cell function will decrease, impacting thyroid hormone production, conversion, and regulation.

In summary, while a ketogenic diet may be attractive for weight loss, it is not suitable for everyone, especially those with thyroid disorders or at risk of developing one. Carbohydrates play a vital role in thyroid function by providing energy, regulating insulin sensitivity, and ensuring the proper conversion and secretion of thyroid hormones. Therefore, it is essential to maintain a balanced diet that includes a steady intake of carbohydrates for optimal thyroid health.

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

The keto diet is a low-carb, high-fat diet. It involves eating very low carb (50 grams or less), high fat, and moderate protein. The keto diet can be an attractive tool for quick weight loss, but it is not a sustainable or healthy method, especially if you have hypothyroidism.

When we don't consume carbs, the body has to figure out how to make carbs to sustain blood sugar. It relies heavily on stress hormones, cortisol, and adrenaline, to do this. Cortisol is responsible for increasing gluconeogenesis in the liver, a process that makes carbs from protein and fat. Adrenaline also supports gluconeogenesis.

Research shows that people with hypothyroidism tend to have higher levels of stress hormones to begin with. We don't want to make dietary changes that make those hormones even higher as can happen with the keto diet.

So what happens when you have high stress hormones? Cortisol, a stress hormone, raises Thyroid Stimulating Hormone (TSH). A high TSH value corresponds with a sluggish thyroid, or hypothyroidism. Cortisol also slows the conversion of T4 to T3 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's focus on high-fat foods can result in lower consumption of micronutrient-dense options, increasing the risk of deficiencies. Research has shown that the keto diet may not provide optimal levels of many essential micronutrients. For example, a study analyzing a 3-day keto meal plan found that out of 24 evaluated micronutrients, 19 were below the recommended intake, with 11 provided at less than 50% of the recommended amount. These included Thiamin, Folate, Pantothenic Acid, Calcium, Copper, Iron, Magnesium, Manganese, Molybdenum, Selenium, and Zinc.

Furthermore, the potential for micronutrient deficiency on the keto diet is not unexpected. The diet can disturb the balance of certain micronutrients due to increased excretion and reduced consumption of micronutrient-rich foods. Over time, this can affect metabolic pathways and specific tissues, potentially leading to serious adverse health effects.

• Vitamin B1 (Thiamin): Thiamin is essential for all body tissues to function correctly and helps turn food into energy. Deficiency can lead to serious health problems such as beriberi and Wernicke-Korsakoff syndrome, affecting breathing, heart function, alertness, and mental abilities. Good keto sources of Thiamin include salmon, liver, beef, mussels, and pork.
• Vitamin B5 (Pantothenic Acid): Pantothenic Acid plays a role in fat, hormone, and carbohydrate synthesis and supports a healthy digestive tract. While clinical deficiency is uncommon, it can affect multiple body systems. Recommended intake is 5 mg per day for adults. Keto-friendly sources include salmon, liver, eggs, chicken, and sunflower seeds.
• Vitamin B9 (Folate): Folate is crucial for preventing neural tube defects, stroke, and certain cancers. It is also linked to improved thyroid function. However, folate deficiency is common, and most people don't consume enough folate-rich foods. Recommended intake is 400 mcg DFE per day for adults. Keto-friendly sources include liver, asparagus, okra, spinach, collard greens, and broccoli.
• Vitamin B7 (Biotin): Biotin is essential for skin, hair, eye, liver, and nervous system health and is crucial during pregnancy. Deficiency is rare but can cause lethargy, paresthesia, depression, dermatitis, and hair loss. Recommended intake is 30-35 mcg per day for adults, with higher amounts suggested during pregnancy and lactation. Keto-friendly sources include beef liver, eggs, and salmon.
• Vitamin D: Vitamin D is well-known for its role in skeletal growth and strong bones. Deficiency can lead to rickets in children and osteomalacia in adults. It is recommended to get vitamin D from sunlight exposure or food sources such as liver, eggs, fatty fish (salmon, tuna, sardines), and dairy products.
• Vitamin E: Vitamin E is a powerful antioxidant that protects cells from damage caused by free radicals. It is essential for maintaining healthy cells and reducing the risk of atherosclerosis. Deficiency is rare but can cause skeletal muscle pain, weakness, and degenerative neurological problems. Recommended intake is 15 mg per day for adults. Keto-friendly sources include wheat germ oil, sunflower seeds, almonds, spinach, and broccoli.
• Calcium: Calcium is the most abundant divalent cation in the body, crucial for bone and teeth health, muscle contraction, blood clotting, and enzyme activation. Deficiency can lead to neuromuscular and cardiovascular issues, changes in mental status, and problems like osteoporosis and cataract. Recommended intake is 1,000-1,400 mg per day for adults. Keto-friendly sources include sardines, clams, oysters, turnip and mustard greens, and broccoli.
• Magnesium: Magnesium is essential for supporting the kidneys, heart, muscles, and nervous system. Deficiency can cause issues such as tetany, rickets, osteomalacia, and osteoporosis. Recommended intake is 400-420 mg per day for adults.
• Manganese: Manganese is a trace mineral with various roles in the body.
• Potassium: Potassium is necessary for the proper functioning of the kidneys, heart, muscles, and nervous system. Deficiency can lead to hypokalemia, causing symptoms such as muscle weakness, fatigue, and heart rhythm abnormalities. Recommended intake is 4,700 mg per day. Keto-friendly sources include animal-based foods and root vegetables like potatoes, sweet potatoes, and beets.
• Sodium: Sodium is a major mineral required for maintaining electrolyte balance in body fluids.

To avoid micronutrient deficiencies on the keto diet, it is crucial to focus on nutrient-dense food choices and consider supplementation. Prioritizing a variety of micronutrient-rich foods, such as those listed above, can help ensure adequate intake. Additionally, working with a registered dietitian or nutritionist can help individuals optimize their keto diet to meet their unique needs and prevent deficiencies.

Keto may be unsustainable

The keto diet is a high-fat, moderate-protein, and low-carbohydrate eating pattern. It is often touted as a magic bullet for weight loss, but it is not for everyone. The keto diet is unsustainable when compared to a Mediterranean diet. The body is not designed to withstand an unbalanced diet that requires excessive willpower. Furthermore, the weight loss from the keto diet is likely to come back. In fact, most people who attempt weight loss gain back the weight they lose and sometimes even more.

The keto diet is challenging to follow correctly, with over 50% of people failing to adhere to a ketogenic diet in many medical studies. This is because the keto diet is restrictive in nature, and it is hard to get the right balance of nutrients. The keto diet is also not intended to be adhered to long-term.

The keto diet can also be harmful to health. It is associated with an increase in "bad" LDL cholesterol, which is linked to heart disease. It can also cause nutrient deficiencies, liver problems, kidney problems, constipation, fuzzy thinking, and mood swings.

Therefore, it is important to talk to a doctor and a registered dietitian before attempting a ketogenic diet. There may be other weight-loss approaches that are safer and more sustainable.

Keto can cause inflammation

The ketogenic diet is a low-carb, high-fat, and moderate-protein eating pattern that has gained immense popularity in recent years. While it is often touted as a magic bullet for weight loss, it is not for everyone and can have some detrimental health impacts. One potential downside of the keto diet is that it can cause inflammation in the body. Here are some reasons why keto can lead to inflammation:

Impact on Thyroid Hormones

The keto diet can negatively impact hormone balance, particularly thyroid hormones. The thyroid gland, located in the front of the neck, plays a crucial role in regulating the body's functions, including metabolism. The thyroid secretes two hormones: T4, the inactive form, and T3, the active form that plays a role in metabolism. Research indicates that periods of starvation, which the keto diet mimics, and weight loss from the keto diet can lower T3 levels, leading to potential weight gain. This is because when the body senses caloric/carbohydrate restriction, it lowers T3 production to conserve energy. As a result, individuals on a keto diet may experience increased tiredness and weight gain over time.

Stress and Cortisol

The keto diet can put the body into a state of stress as it has to figure out how to make carbohydrates to sustain blood sugar levels. This reliance on stress hormones, such as cortisol and adrenaline, can lead to higher cortisol levels. Elevated cortisol levels are associated with an increased risk of diabetes and heart disease. Additionally, high cortisol levels can slow down the conversion of T4 to T3, further impacting thyroid function.

Micronutrient Deficiencies

The keto diet restricts carbohydrate intake to 50 grams or less per day, leading to the elimination or reduction of nutrient-dense carbohydrate foods. Carb-rich foods like grains, lentils, fruits, and vegetables are excellent sources of vitamins and minerals. By eliminating these foods, individuals on a keto diet may put themselves at risk of vitamin and mineral deficiencies. Specifically, it can be challenging to obtain sufficient amounts of potassium and vitamin C on a keto diet. Potassium is essential for supporting the kidneys, heart, muscles, and nervous system, and vitamin C is a powerful antioxidant that aids in reducing inflammation and improving thyroid function.

Gut Microbiome

The keto diet's low fiber and high-fat content can also impact the health of the gut microbiome. Recent research has indicated that a long-term ketogenic diet may lead to lower levels of gut bacteria that protect the gut lining. This can potentially damage the gut and disrupt the balance of the microbiome, which is crucial for overall health.

Social and Sustainability Challenges

Adhering to the keto diet can be challenging, especially in social settings. The restriction of carbohydrate-rich foods like bread, rice, cakes, and snacks can make it difficult to find suitable options when eating out or socializing. Additionally, the keto diet may not be sustainable in the long term. The weight loss achieved through keto may not be maintained, and individuals may regain the lost weight or even gain more.

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