 Dehydroepiandrosterone, DHEA, is the most abundant steroid hormone circulating in the blood, or rather pro-hormone. It's produced largely by the adrenal glands and is then converted locally in tissues into androgens, male sex hormones, or astrogens, female sex hormones. DHEA production in the body peaks between the ages of 25 to 35 and then gradually starts to decline about 2% every year. By one's 80s, DHEA production is down about 80% from peak values in early adulthood. Cross-sectional studies found a link between low DHEA levels and impaired sexual function, less vitality, depressed mood, lower bone mineral density, and compromised cognitive performance in terms of executive function, concentration, and memory. Combined with interventional studies done on rodents showing a wide range of beneficial effects, DHEA was heralded as an anti-aging superhormone panacea, even though rodent adrenal glands don't even produce this stuff. But US DHEA sales grew to more than $50 million a year on the premise that replenishing youthful levels might have restorative effects. Given the premarine debacle with estrogen replacement, showing that the reversing of age-related hormone decline can sometimes do more harm than good, clinical trials were desperately needed. But because DHEA can't be patented, there's been little research interest among drug companies to study it. In fact, part of its mass appeal is that due to a legal loophole, DHEA is the only steroid that's not considered a controlled substance and therefore is available over-the-counter as a quote-unquote dietary supplement rather than a prescription-only drug. Thankfully, a series of long-term, high-quality, randomized controlled trials started to be published within the last 20 years, and early enthusiasm was replaced by a sober skepticism as the quote-unquote panacea repeatedly failed to beat the placebo. The promised DHEA fountain of youth was drying up. A review of about two dozen randomized controlled trials of oral DHEA and post-menopausal women failed to find evidence of improvements in sexual function, psychological well-being, or cognitive performance. However, there may be a role for intravaginal DHEA for vaginal atrophy, which I covered before. A meta-analysis of about two dozen randomized controlled trials of DHEA in elderly men similarly found no evidence of benefits for metabolism, bone health, sexual function, or quality of life. Nor does there seem to be a cognitive benefit. The only benefit found in men was a relatively trivial drop in body fat compared to placebo, less than one pound over span of eight months. But in women, DHEA may benefit fertility. Fertility in women starts declining gradually, but significantly at age 32, but then more rapidly after age 37, but DHEA may help. Side effects of taking DHEA supplements include acne, oily skin and hair, and an increase in body hair and blood levels of the cancer-promoting growth hormone IGF1. As with any supplement, there are concerns about quality control issues. Some so-called DHEA supplements just blatantly lie and have no DHEA whatsoever, or up to like 150% of the listed dose. For these and other reasons, DHEA supplements are not recommended. Are there natural ways to boost DHEA, for example, for the fertility benefit? Lower protein intake is associated with higher levels, and an interventional trial found increasing fiber intake actively raised levels. So what about putting them together? Enter short-term impact of a lacto-vegetarian diet. After just five days on an egg-free vegetarian diet, blood levels of the DHEA precursor rose nearly 20%. Or you can do it the other way, take those already eating a plant-based diet, and switch them to a conventional diet, and their DHEA drops up to nearly 20%. The bodies of those eating plant-based appear to hold onto the hormone better, less urinary excretion, which is normally something you only see in fasting.