Hormones
Episodes
Dr. Rhonda Patrick discusses xylitol safety, strategies to reduce hemoglobin A1C, klotho and dementia risk, and the timing of hormone replacement therapy.
Dr. Rhonda Patrick discusses resistant starch, red light therapy risks, stem cells, and the link between benzodiazepines and dementia in her latest Q&A session.
In this clip, Dr. Martin Gibala delves into the nuances of sex-based differences in exercise response and their implications for individual outcomes.
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Rhonda Hormones Diabetes Cholesterol Omega-3 Dementia Curcumin Protein Blood Sugar Berberine AcetaminophenDr. Rhonda Patrick discusses xylitol safety, strategies to reduce hemoglobin A1C, klotho and dementia risk, and the timing of hormone replacement therapy.
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Rhonda Alzheimer's Cancer Sleep Hormones Omega-3 Stem Cells Sauna Blood Sugar Polyphenol Red Light TherapyDr. Rhonda Patrick discusses resistant starch, red light therapy risks, stem cells, and the link between benzodiazepines and dementia in her latest Q&A session.
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In this clip, Dr. Martin Gibala delves into the nuances of sex-based differences in exercise response and their implications for individual outcomes.
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Rhonda Brain Diet Aging Hormones Omega-3 Fasting Memory Testosterone Dementia Development Skin CocoaDr. Rhonda Patrick explores taurine's longevity role, cocoa flavanols, training adaptations, and oral hyaluronic acid in a Q&A.
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Heat therapy (saunas, exercise, hot baths) can enhance slow-wave sleep. This video explores exercise and heat's joint role in sleep regulation.
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Rhonda Vitamin D Microbiome Hormones Omega-3 Melatonin Bone Time-Restricted Eating Cardiovascular SupplementsDr. Rhonda Patrick answers audience questions on various health, nutrition, and science topics in this Q&A session.
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In this clip, Bruce Ames explains how vitamin D functions as both a vitamin and a hormone.
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In this clip, Dr. Satchin Panda talks about how time-restricted eating affects leaky gut and systematic inflammation.
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In this clip, Dr. Rhonda Patrick describes the potential interaction between sulforaphane and iodine and stresses that iodine-deficient individuals or those with hypothyroidism should work with their physician to monitor thyroid hormone levels.
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In this clip, Tim Ferriss and Dr. Rhonda Patrick discuss vasopressin and its effects on pair bonding in both animals and humans.
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Rhonda Vitamin D Brain Cancer Epigenetics Aging Hormones Diabetes Vitamin C Antibiotics Vitamin K Sulforaphane Sauna Glutathione Oxidative Stress NAD+ CardiovascularDr. Rhonda Patrick answers audience questions on various health, nutrition, and science topics in this Q&A session.
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In this clip, Dr. Valter Longo describes the IGF-1 pathway and explains how defects in the pathway influence disease risk.
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Dr. Rhonda Patrick describes the dual nature of biochemical pathways involved in aging and explains how exercise tips the balance toward its beneficial properties.
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Dr. Valter Longo discusses the longevity-conferring effects of diminishing the pro-aging IGF-1 pathway.
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In this clip, Dr. Ruth Patterson discusses how eating in accordance with the body's natural circadian rhythm may reduce the risk of breast cancer.
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Dr. Dale Bredesen discusses treatments that may reverse symptoms of mild cognitive decline and Alzheimer’s disease.
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Sauna Exercise Brain Aging Hormones Performance Insulin Resistance Depression Stress Heat Stress MuscleDr. Rhonda Patrick discusses how conditioning the body to heat stress through sauna use, called "hyperthermic conditioning" may cause adaptations that increase athletic endurance (by increasing plasma volume and blood flow to heart and muscles) and potentially even muscle mass.
Topic Pages
News & Publications
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Sleep disruption reduces the newly discovered hormone 'raptin,' potentially increasing appetite and promoting weight gain. www.nature.com
Sleepless nights don’t just leave you tired—they may also interfere with your body’s ability to regulate hunger. Researchers have long known that poor sleep increases the risk of obesity, but the biological link has remained elusive. A recent study found that a sleep-triggered hormone called raptin helps control appetite and may explain why people who don’t get enough sleep are more likely to gain weight.
Researchers examined brain activity, hormone levels, and eating behavior under different sleep conditions in mice and humans. They identified a previously unknown hormone, which they named raptin, and tracked where and when it was released. They also studied the effects of a genetic variant that blocks raptin production and examined hormone levels in people with sleep deficiency, obesity, and nighttime eating syndrome.
They discovered that raptin is produced in a part of the brain that regulates hunger and hormone secretion and is released during sleep. When sleep is disrupted, raptin levels drop. In lab experiments, raptin acted on specific receptors in the brain and stomach to reduce appetite and slow stomach emptying. People with obesity and sleep deficiency had lower levels of raptin, while those who underwent therapy to improve sleep showed increases in the hormone. A genetic variant that blocks raptin production was linked to night-time overeating and obesity.
These findings indicate that raptin explains how sleep influences weight gain and appetite. Learn more about the effects of sleep deprivation in Aliquot #27: Health consequences of sleep deprivation, part I: Metabolic & immune health and Aliquot #28: Health consequences of sleep deprivation, Part 2: Mental & cognitive health
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Vitamin D, best known for maintaining calcium balance and bone health, is critical in many physiological processes, including blood pressure regulation, immune function, and cell growth. Evidence now suggests vitamin D also influences body composition and muscle strength. A recent study in mice showed that high vitamin D intake increased muscle strength and mass without altering body weight.
Researchers fed mice one of three diets, providing low, normal, and high doses of vitamin D for four weeks to achieve deficient, insufficient, and sufficient vitamin D concentrations, respectively. At the end of the fourth week, they assessed the animals' grip strength (a measure of muscle function) and body composition.
They found that compared to low or normal vitamin D intake, high intake increased grip strength and lean mass and decreased fat mass without altering the animals' weights. High intake also impaired myostatin production and increased the animals' leptin sensitivity and energy expenditure without altering their activity levels.
Leptin is a satiety hormone that signals the brain to balance energy. When body fat increases or decreases, blood concentrations of leptin change accordingly. Higher leptin levels signal the brain to reduce hunger and boost energy use. However, in obesity, the body becomes less responsive to leptin, dulling its effects on appetite and energy expenditure.
These findings suggest that vitamin D influences body composition and metabolism by preferentially allocating calories toward muscle development and overall growth rather than fat storage. They also highlight the intricate relationship between obesity and vitamin D status. Learn more about vitamin D in our comprehensive overview article.
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Growth hormone cuts fracture risk in half for women with osteoporosis. endocrinenews.endocrine.org
Growth hormone improves bone density and reduces the risk of fractures in women with osteoporosis, according to a 2015 study. Women who received growth hormone were half as likely to experience a fracture over a 10-year period than women who did not.
The study involved 80 women (50 to 70 years old) who had osteoporosis and were taking estrogen-based hormone replacement therapy. Researchers randomly assigned the women to receive daily injections of either a low or high dose of growth hormone for three years or a placebo for 18 months. All the women took daily vitamin D and calcium supplements for the study’s duration. The researchers measured the women’s body composition and bone mass at regular intervals.
They found that women who received growth hormone injections showed marked improvements in their bone mineral density and bone mineral content compared to those who received the placebo. Over the 10-year period, the number of fractures among the women who received growth hormone dropped from 56 percent to 28 percent, whereas fractures among those who received the placebo increased from 8 percent to 32 percent.
Growth hormone, a peptide hormone produced in the pineal gland, promotes growth in childhood and adolescence. During middle age, growth hormone production decreases. Some evidence suggests that because growth hormone is secreted at night (during sleep), not getting enough sleep may hinder growth hormone release, exacerbating age-related bone loss. Learn how body temperature can influence how well you sleep at night in this clip featuring Dr. Matthew Walker.
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Obstructive sleep apnea may have a suppressive effect on serum testosterone levels in men, independent of BMI and age. (2021) onlinelibrary.wiley.com
Sleep apnea increases the risk of low testosterone.
Men with sleep apnea are more likely to have low testosterone levels, according to a 2021 study. Men with severe apnea are at the greatest risk of low testosterone.
Researchers reviewed the findings of 18 studies involving more than 1,800 men that examined links between sleep apnea and male testosterone levels. Then they analyzed a subset of the studies after matching the men’s age, body mass index, and severity of their sleep apnea.
They found that the men with sleep apnea were more likely to have low testosterone levels, even after considering their age and body mass index. However, the subset analysis revealed that this relationship was only notable for those with severe apnea.
Sleep apnea is a common, but serious, sleep disorder characterized by brief moments of paused or shallow breathing. People with sleep apnea are at greater risk of high blood pressure, stroke, abnormal heart rhythms, heart failure, diabetes, weight gain, and heart attacks.
This review identifies links between sleep apnea and testosterone levels. It also underscores the importance of diagnosing and treating sleep apnea, particularly among men whose apnea is more severe.
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The contraceptive pill and hormone replacement therapy may protect against brain aneurysm. (2011) www.eurekalert.org
From the article:
Oestrogen helps maintain the structure of blood vessel walls by promoting the division of endothelial cells within the vessel walls, which is important for repair if the vessels become damaged. However, oestrogen levels drop significantly at the menopause.
Women have been shown to be more likely to develop a cerebral aneurysms after the age of 40 years, and aneurysms are most likely to rupture between the ages of 50 and 59 years.
The authors asked 60 women with cerebral aneurysms about their use of the oral contraceptive pill and hormone replacement therapy, and this was compared with usage in 4,682 other women drawn from the general public.
Women with cerebral aneurysms were found to have been significantly less likely to have taken oral contraceptives or hormone replacement therapy. Women with cerebral aneurysms also had an earlier average age of menopause.
Previous studies have shown that use of the oral contraceptive pill protects against haemorrhagic stroke in later life, while women who start their periods early and/or do not have children are at greater risk.
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Early menopause may be linked to increased risk of brain aneurysm. (2012) www.eurekalert.org
From the article:
The average age at which women in both groups had started the menopause was similar, and analysis of the results showed that later menopause and use of hormone replacement therapy (HRT) protected against the risk of a cerebral aneurysm, lessening the risk by 21% and 77%, respectively.
Premature menopause - before the age of 40 - had occurred in one in four (26%) of the women who had had an aneurysm compared with around one in five (19%) of those in the comparison group.
And each successive four year increase in the age at which a woman went through the menopause lessened the likelihood of a cerebral aneurysm by around 21%.
Smoking did not seem to be linked to an increase in risk, while alcohol consumption was of borderline significance.
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Estradiol protects male rats from aortic aneurysms. (2004) www.sciencedaily.com
From the article:
At this week’s American College of Surgeons meeting in New Orleans, Derek T. Woodrum, M.D., a U-M resident in general surgery, will present new research results showing that smooth muscle cells from aortas of male rats contain 2.5 times more destructive MMP-9 protein and 10 times the level of MMP-9 gene expression compared to the same cells from female rat aortas. Known to be involved in AAA [abdominal aortic aneurysms] formation, MMP-9 is a cell-digesting enzyme that eats away at the wall of the aorta, leaving it vulnerable to expansion and rupture.
However, when Woodrum treated male rats with estradiol, a form of the female hormone estrogen, and then tested their aortas, he found that MMP-9 activity was substantially decreased. At this year’s meeting, Woodrum will receive an American College of Surgeons “Excellence in Research Award” for his study.
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“Earlier studies have demonstrated that increased estrogen systemically inhibits the development of AAAs,” Upchurch says. “Dr. Woodrum’s study extends earlier research and suggests that there also is something inherent in males that increases MMP-9 and may lead to greater AAA formation.”
“Estrogen affects production of MMP-9 by white blood cells called macrophages,” Upchurch adds. “MMPs degrade collagen and elastin, two major proteins in the aortic wall.