The Best Diet For Thyroid Health

Saladino emphasizes that while comprehensive blood work is ideal, monitoring body temperature and pulse rate offers accessible, tangible metrics for assessing thyroid health. A consistently low morning temperature (below mid-97s F) and a resting pulse rate below 60-70 bpm can signal that the body is in a 'scarcity' mode, with a furnace that isn't burning hot enough. He contrasts this with his own experience on a strict carnivore diet, where his body temperature was half a degree to 0.7 degrees Fahrenheit lower, making him feel chronically cold. He suggests that a healthy, vital state is characterized by a warmer body temperature and a pulse rate in the 60s-70s, reflecting adequate energy production.

Saladino stresses that a single TSH test is inadequate for a complete thyroid assessment. He explains that TSH (Thyroid Stimulating Hormone) is released by the pituitary to signal the thyroid, but it's only one piece of the puzzle. The thyroid then produces T4 and T3 (the active form), which are further modified in peripheral tissues. To truly understand thyroid function, one needs to measure TSH, free T3, free T4, and reverse T3. He also notes that nutrient analysis for iodine, selenium, and zinc is crucial, as these are essential building blocks for thyroid hormone production. He highlights that the commonly accepted TSH reference range is too broad, leading to many cases of subclinical hypothyroidism being missed.

Saladino identifies sleep as a foundational element for overall health and thyroid function. He explains that insufficient sleep acts as a stressor, leading to an increase in reverse T3 (an inactive form of thyroid hormone) and a decrease in active thyroid hormones. This directly impacts the body's ability to regenerate cells and tissues, including the thyroid, and disrupts hormonal balance. Optimal sleep is presented as a central 'onion' layer, around which other healthy practices (light exposure, grounding, nutrition) revolve to support its quality. He emphasizes that without proper sleep, the body cannot effectively signal abundance, leading to a state of scarcity that negatively affects energy production.

Saladino argues that caloric and carbohydrate restriction, often seen in biohacking or weight loss regimens, sends a signal of 'scarcity' to the body, which the thyroid interprets by downregulating metabolism. He notes that carbohydrates, particularly from sources like honey and fruit, are 'pro-thyroid' and have historically been signals of abundance for humans. He contrasts this with his personal experience on a strict carnivore diet, where his body temperature was lower, and he felt chronically cold, indicating a state of scarcity. He suggests that a moderate intake of carbohydrates (e.g., 50-100 grams/day from healthy sources) is beneficial for thyroid health and overall energy, even for diabetics, as long as the carbohydrates are not from problematic sources.

Saladino emphasizes the importance of natural light cycles for health. He recommends getting outdoor photons, full-spectrum light, and infrared light first thing in the morning, avoiding direct sun gazing but ensuring exposure to natural light. He also highlights the role of infrared light in melatonin production within mitochondria, suggesting that systemic melatonin deficiency is common due to lack of infrared exposure, which cannot be fully compensated by melatonin supplements. In the evening, he advises moderating blue light and flickering lights to support natural sleep cycles and prevent overactivation of the sympathetic nervous system, which can negatively impact thyroid function.

Saladino cautions against the 'more is better' mentality with hormetic stressors. He explains that while practices like saunas and cold plunges can have benefits, overdoing them constitutes a significant stressor on the body. This stress can lead to a 'scarcity' signal, negatively impacting energy production and thyroid function. He provides specific examples: saunas that are too hot can 'cook your brain' and are linked to dementia, while also temporarily impairing male fertility by overheating testicles. Similarly, overly cold or prolonged cold plunges can suppress the immune system. He advocates for a balanced approach, using these tools for neurochemical benefits and clarity, but within sensible limits, such as a 48°F cold plunge for short durations.

Saladino asserts that a low body temperature is a reflection of a 'colder burning engine' in human metabolism, indicating that the body is not efficiently producing energy. He references Ray Peat's concept that a healthy, vital human should have a 'furnace burning hot,' meaning a well-functioning metabolism. He argues that the idea of a 'candle burning twice as bright burns half as long' does not apply to human physiology; instead, a robust metabolism (a brighter burning candle) is associated with a longer, healthier life. This perspective directly challenges the longevity claims made by some who pursue extreme caloric restriction and other practices that lower body temperature.

While acknowledging some benefits of mild omega-3 supplementation, Saladino argues that exceeding a certain threshold (e.g., 4 grams/day) can lead to adverse effects, such as an increased incidence of atrial fibrillation. He attributes this to the oxidative load of polyunsaturated fatty acids (PUFAs), which are prone to oxidation due to their double bonds. He also points out that many commercial fish oil supplements are already oxidized before consumption, further contributing to oxidative stress. He suggests that adequate omega-3s can be obtained from egg yolks and grass-fed meat, making additional supplementation unnecessary for most people.

Saladino argues that fish, regardless of type, accumulate contaminants from the ocean, acting as filters for human waste. He claims that eating fish more than once or twice a week will likely elevate heavy metal levels in the body, which are known to cause physiological problems. He points out that while he enjoys the taste of various fish and seafood, the attendant risks of contamination are now too significant to ignore for frequent consumption. He contrasts this with his own low heavy metal levels, which he attributes to not eating fish.

He mentions studies showing oxalate deposition in the thyroid glands of all individuals examined post-mortem, with lower levels in those with Hashimoto's, suggesting a possible immune reaction or clearing mechanism. Saladino posits that oxalates, for which there is no known physiological role in the thyroid, could act as a 'nidus or trigger' for autoimmune thyroid conditions like Hashimoto's. This raises questions about the health benefits of high-oxalate foods like spinach, almonds, and rhubarb, especially for individuals with existing thyroid concerns.

Saladino explains that microRNAs are small RNA fragments that control gene expression, acting as 'blueprints' for cellular reprogramming. He suggests that the benefits of consuming organs, and potentially raw milk, might stem from these microRNAs surviving digestion and influencing human physiology. He cites examples of preclinical research where microRNA-filled exosomes are used to regenerate cartilage, hair follicles, and treat acute respiratory distress syndrome. This theory offers a deeper explanation for the 'like-for-like' principle often associated with organ consumption (e.g., eating thyroid to support one's own thyroid).