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How to Control Your Metabolism by Thyroid & Growth Hormone

Episode 17 Apr 26, 2021 1h 46m 34 insights
This episode discusses metabolism and how our thyroid hormone and growth hormone control our metabolism. I also clarify that metabolism isn't just about burning energy, it’s about converting energy from different sources into fuels for building and repairing our tissues such as muscle, brain, and tendons and mobilizing energy from body fat storage. I discuss the role of iodine, selenium, and salt for thyroid health, and how specific exercise protocols, amino acids and temperature can dramatically shift levels of growth hormone release in waking and in sleep. I also describe the current landscape of prescription compounds, peptides and other factors for changing levels of thyroid and growth hormone, and some of their risks. Throughout the episode, mechanisms and tools grounded in specific mechanisms are discussed. Supplements from Thorne https://www.thorne.com/u/huberman
Actionable Insights

1. Optimize Deep Sleep for GH

Prioritize and optimize for slow-wave (deep) sleep, especially in the first half of the night, as this brain activity triggers the majority of growth hormone secretion crucial for tissue repair and metabolism.

2. Fast Before Sleep for GH

Avoid eating within two hours of going to sleep to ensure blood insulin and glucose levels are relatively low, which is a necessary condition for optimal growth hormone release during early sleep.

3. Warm Up & Exercise for GH

Perform a 10-minute body-warming warm-up before engaging in 60-75 minutes of high-intensity exercise (weight training or endurance, not to absolute failure) to significantly increase growth hormone during and after the workout.

4. Sauna for Massive GH Boost

Engage in deliberate hyperthermia (e.g., sauna at 175-210°F / 80-100°C for 20-30 minutes, followed by 30 minutes of cooling, repeated for several days) to dramatically increase growth hormone release (up to 16-fold) and reduce cortisol levels, but proceed with extreme caution and medical clearance.

5. Offset GH Decline with Behaviors

Actively engage in behaviors known to increase growth hormone, such as specific exercise protocols and sleep optimization, to potentially offset the significant age-related decline in growth hormone levels that occurs in the 30s and 40s.

6. Ensure Adequate Iodine Intake

Make sure you are getting sufficient iodine through your diet, as it is absolutely essential for the thyroid gland to produce T3 and T4 hormones, which are crucial for overall metabolism, tissue repair, and cognitive function.

7. Boost Selenium for Thyroid

Increase your selenium intake, potentially by consuming 6-8 Brazil nuts (which contain ~550mcg of selenium) or other selenium-rich foods, because selenium is important for L-tyrosine and iodine to interact and produce thyroid hormones.

8. Consume Sufficient L-Tyrosine

Ensure you consume enough L-tyrosine from sources like meat and nuts, as this amino acid works with iodine in the thyroid to produce T3 and T4 hormones, supporting healthy metabolism.

9. Nourish Thyroid for Brain

Consume foods and nutrients (iodine, selenium, L-tyrosine) that support healthy thyroid hormone levels, as robust thyroid function is crucial for brain metabolism and cognitive function, given the brain accounts for 75% of basal metabolic needs.

10. Consult Doctor for Thyroid

Always consult a doctor for blood tests if you are concerned about your thyroid hormone levels or before supplementing iodine or selenium, as manipulating hormone levels is a serious matter requiring professional medical advice.

11. Use Extreme Hyperthermia Caution

Exercise extreme caution and consult a doctor before attempting deliberate hyperthermia, as overheating is dangerous and can lead to severe health consequences, including cooking brain neurons and death.

12. Physician Consultation for Hormones

Always consult a physician before considering prescription hormones or peptides, as these compounds are legally available only through a doctor and medical guidance is essential for safety and appropriate use.

13. Exogenous Hormones Suppress Natural Production

Be aware that injecting exogenous hormones (e.g., thyroid, testosterone, growth hormone) will typically shut down the body’s natural production, which is a critical consideration for long-term planning as stopping injections may lead to a period of deficiency or permanent shutdown.

14. GH Can Stimulate Tumor Growth

Be aware that increased growth hormone levels, especially constant ones from injections, can stimulate the growth of existing tumors, which is a significant health risk necessitating careful medical screening.

15. Arginine Lowers Blood Pressure

Be aware that arginine and L-citrulline cause vasodilation and can lower blood pressure, which can be dangerous for individuals with heart conditions or those on blood pressure medication, requiring medical consultation.

16. Cool Down After Exercise

Actively cool down your body to normal temperature relatively quickly after exercise, as rapid cooling helps maximize the subsequent increase in growth hormone release during the following night’s sleep.

17. Low Glucose for Exercise GH

Ensure blood glucose levels are relatively low before and during exercise aimed at boosting growth hormone, and avoid ingesting caloric sugars, as high blood glucose can suppress growth hormone release.

18. Meditate for Delta Brain Waves

Practice 20 minutes of traditional sitting meditation daily, as certain types of meditation can induce slow-wave delta-type brain activity, which is associated with triggering growth hormone release similar to deep sleep.

19. Micro-Dose Melatonin for Sleep

If considering melatonin supplementation, use very low doses (e.g., 500 micrograms) to potentially aid the transition to slow-wave sleep, as this may shift early night sleep patterns towards more delta wave activity and improve growth hormone release.

20. Sex-Specific Exercise for GH

Women should aim for at least 30 minutes of exercise for maximum growth hormone and IGF-1 peaks, while men should continue for the entire 60 minutes, as GH and IGF-1 release patterns during exercise are sex-dependent.

21. Arginine/Citrulline for GH (Caution)

Consider supplementing with L-citrulline (or arginine) to increase growth hormone, but be aware of the need for low blood glucose, potential GI issues with high arginine doses (3-10g), and that L-citrulline may be a more effective route to increase blood arginine levels.

22. Arginine & Exercise GH Interaction

Understand that combining arginine supplementation with exercise does not synergistically increase growth hormone beyond what either would achieve alone, as the effects appear to be clamped at about 300-500% increases.

23. Alternative Deliberate Hyperthermia

If a sauna is unavailable, consider alternative methods for deliberate hyperthermia, such as wearing plastic body suits or creating a hot, steamy room environment, always with extreme caution due to the inherent risks of overheating.

24. Limit Emulsifiers in Diet

Be cautious about consuming highly processed foods containing emulsifiers, as they can strip the gut’s mucosal lining and impair satiety signals, potentially leading to overeating.

25. Adjust Iodine for Diet Type

Adjust your iodine intake based on your diet type; if purely plant-based with many cruciferous vegetables or purely meat-based/keto, ensure sufficient iodine, as these diets can increase requirements or interfere with thyroid function.

26. Gradual Carb Reintroduction Post-Keto

If transitioning from a long-term ketogenic diet, reintroduce carbohydrates gradually, as ketogenic diets can lower thyroid hormone levels, and a sudden reintroduction of carbs may lead to rapid weight gain.

27. Selenium for Broader Health

Consider ensuring sufficient selenium intake for potential health benefits beyond thyroid function, such as reducing the risk of preeclampsia, prostate cancer, and acne.

28. Sweet Taste Triggers Insulin

Be aware that any very sweet taste, even from non-caloric sweeteners or just the smell of baked goods, can trigger an insulin response, which helps manage blood sugar and insulin secretion.

29. Understand Peptide Secretagogues

Understand that peptides like Sermorelin are secretagogues that stimulate the body’s own release of hormones (e.g., GH) from the pituitary, rather than directly injecting the hormone itself, which is a distinct approach from direct hormone replacement.

30. Peptides Influence Gene Expression

Be aware that some peptides can alter gene expression, potentially leading to sustained hormone production even after cessation of use, which can be both beneficial and risky if not carefully managed.

31. Review Books with Blinkist

Use Blinkist to review non-fiction books by listening to or reading 15-minute summaries, as it helps jog memory and uncover key points that might have been missed during initial consumption, enhancing learning.

32. Drink Mushroom Coffee for Benefits

Consider drinking Four Sigmatic mushroom coffee, which contains lion’s mane and chaga mushrooms, as these may slightly reduce anxiety, lower depression symptoms, and offset cognitive decline.

33. Choose Low-Carb MunkPak Snacks

Consider MunkPak bars as a delicious, low-carb, keto-friendly snack with 1 gram of sugar or less, which can support alertness and focus throughout the day.

Disregard the belief that a food’s shape indicates its health benefits for specific organs (e.g., walnuts for brain), as there is no scientific evidence to support this idea.