The ketogenic diet, commonly known as the keto diet, has become a popular strategy for weight loss and health improvement. It is characterized by a low-carbohydrate, high-fat, and moderate-protein eating pattern. While many individuals have successfully used the keto diet to achieve their health goals, it is crucial to consider its potential impact on hormone balance, particularly thyroid hormones.
A Brief History of the Keto Diet
Initially, the keto diet was developed as a treatment for childhood epilepsy. However, with the advancement of anti-epileptic medications, its popularity declined. In recent years, the keto diet has experienced a resurgence, largely due to the promotion of its weight-loss benefits by celebrities and social media influencers.
Understanding the Ketogenic Diet
The ketogenic diet involves a specific macronutrient ratio:
- 55 to 60% fat
- 30 to 35% protein
- 5 to 10% carbohydrate
For a standard 2000-calorie diet, this translates to a daily carbohydrate intake of no more than 50 grams. This significant reduction in carbohydrates triggers a metabolic state called ketosis.
Ketosis: How It Works
Ketosis occurs when the body is deprived of its preferred energy source, carbohydrates. In response, it begins to break down fat stores into ketone bodies, which are then used as an alternative fuel source for energy. The heart, muscle tissue, kidneys, and brain can utilize ketone bodies, while red blood cells and the liver cannot. Ketone bodies also possess cell-protective antioxidant properties.
Read also: Easy Low-Carb Cheese Crackers
The transition into ketosis can be accompanied by symptoms known as the "keto flu," which may include:
- Brain fog
- Sore muscles/cramps
- Dizziness
- Keto-breath
- Headache
- Fatigue
These symptoms are typically temporary and can be alleviated by staying hydrated. The presence of ketosis can be confirmed through urine strips, breath tests, or blood tests.
The Thyroid Gland: Its Role in Metabolism
The thyroid gland, located in the front of the neck, plays a vital role in regulating various bodily functions, including:
- Heat regulation
- Heartbeat
- Metabolism
- Speed of digestion
- Muscle contraction
The thyroid gland produces two hormones:
- T4 (tetraiodothyronine): An inactive form that converts to T3 as needed.
- T3 (triiodothyronine): The active hormone that regulates metabolism in cells.
Proper T3 levels are essential for maintaining optimal cellular function. High T3 levels can lead to hyperthyroidism, characterized by a rapid heartbeat, while low T3 levels can result in hypothyroidism, causing a slower heartbeat.
Read also: Keto Calorie Counting: A Detailed Guide
Keto Diet and Thyroid Conditions
The keto diet has the potential to negatively impact thyroid hormone levels. Research suggests that both starvation (which the keto diet mimics) and weight loss resulting from the keto diet can lower T3 levels, potentially leading to weight gain.
When the body senses caloric or carbohydrate restriction, it may lower T3 production to conserve energy. This metabolic adaptation aims to increase efficiency and prolong survival during perceived "famine" conditions.
Individuals with thyroid conditions may experience initial positive results on the keto diet but may subsequently develop symptoms such as increased tiredness and weight gain due to decreased T3 production.
Strategies for Maintaining Thyroid Health on Keto
Given the potential risks of combining a keto diet with a thyroid condition, it's crucial to take steps to mitigate those risks and ensure thyroid health.
Individualized Approach
Due to the unique nature of each individual's body, there is no one-size-fits-all approach to determining the safety of the keto diet for those with thyroid conditions. It is crucial to closely monitor how you feel and make adjustments as needed.
Read also: Magnesium Supplements for Keto
If energy levels remain normal, cognitive function is clear, and weight goals are being met, the keto diet is likely not negatively impacting thyroid function. However, persistent adverse symptoms like fatigue or difficulty losing weight may indicate a thyroid hormone imbalance. In such cases, a blood test can help assess hormone levels.
Modifying the Keto Diet
At-home lab testing can provide insights into how the keto diet affects thyroid hormone levels. By tracking the impact of different adjustments on bloodwork, an optimized ketogenic diet can be developed. Some potential modifications include:
- Incorporating intermittent fasting
- Adjusting carb, protein, and fat ratios
- Reducing consumption of potential food sensitivities (e.g., gluten, dairy, soy)
- Balancing lifestyle factors (e.g., sleep, exercise, stress management)
Significant changes in thyroid hormone levels can be observed within a month of implementing these modifications.
Debunking Myths About Keto and Thyroid Health
A common misconception is that the ketogenic diet damages thyroid function by impairing hormone production and worsening symptoms of thyroid conditions. However, a well-planned and nutritious high-fat diet is unlikely to damage the thyroid and may help alleviate hypothyroidism symptoms.
A study published in PLOS ONE found that the ketogenic diet significantly enhanced fat metabolism without negatively affecting the thyroid. While participants showed a reduction in T3 and an increase in T4, they stayed within the normal range, and thyroid-stimulating hormone (TSH) levels remained stable, implying that the thyroid gland continued functioning normally.
Research published in Metabolism further supports this, showing that a low-carb diet increases men’s muscle mass and fat loss while maintaining or improving thyroid hormone levels. These findings imply that the hormonal changes during ketosis reflect a natural metabolic adaptation towards efficient hormone utilization rather than thyroid dysfunction.
However, the type of ketogenic diet you follow can have a significant impact on your thyroid health.
Many ketogenic plans focus primarily on macronutrient ratios and place little emphasis on food quality and nutrient uptake. This can mistakenly lead keto dieters to consume low-quality, ultra-processed, low-carb products that are typically laden with harmful ingredients. Additionally, eating low-quality foods, such as non-organic produce or grain-fed meats, can increase exposure to the herbicide glyphosate, which has been linked to endocrine disruptions and hormonal imbalances.
Research published in Frontiers in Endocrinology studied the influence of glyphosates in relation to hypothyroidism and found that “the risk of hypothyroidism was significantly increased due to contact with these substances.”
Without proper nutritional guidance, reliance on such foods can lead to nutrient deficiencies, food cravings, weight gain, and inflammation, potentially worsening both hyper- or hypothyroid symptoms.
This underscores the importance of following a Healthy Keto diet that prioritizes high-quality, nutrient-dense foods to promote metabolic balance while supporting thyroid health.
Potential Benefits of a Healthy Keto Diet for Thyroid Health
When implemented correctly, a Healthy Keto diet may offer several benefits for individuals with thyroid conditions:
- Improved hormone balance
- Enhanced insulin sensitivity
- Lower inflammation
- Better energy levels
- Weight loss
"Healthy Keto provides essential building blocks for hormone production, including healthy fats and key nutrients such as iodine and selenium," explains Dr. Berg.
Specific Considerations for Hyperthyroidism and Hypothyroidism
Hyperthyroidism
Hyperthyroidism occurs when the thyroid gland secretes too much thyroid hormone, leading to symptoms such as unexplained weight loss, increased appetite, rapid heart rate, frequent bowel movements, and persistent nervousness.
Dietary Recommendations for Hyperthyroidism:
- High-calorie, nutrient-dense diet: To counteract weight loss and provide essential nutrients.
- Avoidance of restrictive diets: Including keto, paleo, vegan, or plant paradox diets.
- Autoimmune protocol (AIP) diet: May be beneficial for individuals with Graves' disease, an autoimmune condition that causes hyperthyroidism.
- Foods to include:
- Leafy greens (spinach): Source of calcium.
- Fatty fish (salmon): Source of vitamin D, which improves calcium absorption.
- Fermented foods (kimchi, kombucha, kefir, sauerkraut): Enhance gut health and may help regulate thyroid function.
- Iron-rich foods: Increase iron levels.
- Fresh fruit (in moderation): 10-40 grams of fructose per day (one to two pieces).
- Olive oil: Reduces inflammation and improves thyroid function.
- Selenium-rich foods: May have benefits in autoimmune thyroid diseases like Graves’ disease.
- Foods to avoid:
- High-iodine foods: Can worsen hyperthyroidism.
- Goitrogens (cruciferous vegetables, legumes, some root vegetables): Thyroid hormone disruptors.
- Gluten: May cause inflammation and damage thyroid health.
- Caffeine: Stimulant that can worsen fast heart rate and heart palpitations.
- Fasting: Is not recommended for hyperthyroidism.
Lifestyle Changes for Hyperthyroidism:
- Rest: Get plenty of rest.
- Exercise: Engage in gentle, restorative exercises.
- Stress reduction: Reduce stress levels with relaxation techniques.
Medical Treatment for Hyperthyroidism:
- Medications: Beta blockers (manage symptoms) and antithyroid medications (block thyroid hormone release).
- Regular blood test monitoring: Measure TSH, free T4, and total T3 levels, along with liver function and complete blood cell count.
Hypothyroidism
Hypothyroidism is a condition in which the thyroid gland does not produce enough thyroid hormone, leading to symptoms such as fatigue, weight gain, slowed heart rate, reduced tolerance to cold temperatures, joint and muscle pain, dry skin or dry, thinning hair, heavy or irregular menstrual periods, fertility problems, and depression.
Dietary Recommendations for Hypothyroidism:
- Anti-inflammatory eating plans: Such as the Mediterranean diet or plant-based diets.
- Foods to include:
- Vegetables, fruits, and whole grains.
- Healthy fats, legumes, and occasional meats.
- Vitamin A, vitamin B12, vitamin D3, iron, selenium, and zinc.
- Fresh vegetables and fruits.
- Fish, chicken, and turkey.
- Healthy fats such as avocados and olive oil.
- Whole grains such as oats and brown rice.
- Beans, nuts, and legumes.
- Foods to limit:
- Excess amounts of iodine (supplements, seaweed, kelp).
- Sugars and processed foods.
- Caffeine and alcohol.
Other Considerations for Hypothyroidism:
- Medication: Hormone replacement medications are prescribed to help ease symptoms of this condition.
- Timing of medication: Take thyroid replacement medications in the morning before breakfast.
- Foods to avoid before/after medication: Soy and grapefruit should be avoided within a few hours of taking medications.
Very-Low-Calorie Ketogenic Diets (VLCKDs) and Thyroid Function
Very-low-calorie ketogenic diets (VLCKDs) have gained popularity as dietary interventions for weight loss and managing chronic diseases. These diets involve a higher proportion of calories from fat (90%) and a smaller proportion (10%) from carbohydrates and proteins.
Impact of VLCKDs on Thyroid Hormones:
Research has shown that a low-calorie, high-fat diet can affect thyroid hormone levels. Weight loss can also influence thyroid hormone levels. Studies have suggested that long-term use of VLCKD for refractory epilepsy may be related to the development of hypothyroidism, with an effect seen in various populations.
VLCKD Protocol:
The VLCKD protocol typically involves three stages: active, re-education, and maintenance.
- Active phase: Reduced carbohydrate intake to induce nutritional ketosis (650-800 kcal/day, less than 30 g daily from vegetables and 20 g per day from olive oil).
- Re-education phase: Gradual reintroduction of other food categories, starting with low glycemic index foods like fruits and dairy (1000-1200 kcal/day, 60-100 g of carbohydrates).
- Maintenance phase: Hypocaloric balanced diet following the Mediterranean diet (1500-2200 kcal).
Contraindications:
Strict contraindications associated with VLCKD include moderate renal failure, type 1 diabetes mellitus, latent autoimmune diabetes in adults, sodium/glucose cotransporter 2 inhibitor use, and cell failure in type 2 diabetes.
Obesity and Hypothyroidism
The connection between obesity and hypothyroidism is a topic of ongoing discussion in the medical world. Some experts suggest that changes in TSH levels may be a consequence of obesity rather than the cause.
Impact of Obesity on Thyroid Function:
- Obesity is associated with thyroid autoimmunity, with leptin produced by adipose tissue as the primary link.
- Small changes in levothyroxine (L-T4) dosage during replacement therapy can cause significant variations in resting energy expenditure in hypothyroid patients.
- There is an inverse relationship between fT4 and BMI, even when fT4 levels are within the normal range.
- Fat accumulation is linked to lower fT4 and higher TSH levels.
- In individuals with obesity, the fT3 to fT4 ratio is positively associated with BMI and waist circumference.
- Weight loss results in a drastic reduction of serum fT3 and TSH.
tags: #keto #diet #hyperthyroidism