Can Human Growth Hormones Make Us Younger?

Did you know that taking human growth hormone, somatotropin, may actually accelerate the aging process. Here’s our first story.

Of all the anti-aging clinic scams, the selling and administration of human growth hormone has been called “perhaps the most blatant and organized form of quackery today.” It all started, promisingly enough, with a small trial published in the New England Journal of Medicine in which twelve men over the age of 60 who got injections of growth hormone gained eight pounds of lean mass over a period of six months, compared to nine guys who weren’t injected. Newspapers around the world heralded the results. Anti-aging clinics popped up to offer the injections for $4700 per month or more, and the popular press churned out books extolling the hormone’s age-reversing properties. After all, that’s how much muscle mass one might lose over 10 to 20 years of aging. That’s assuming, though, that what they gained was muscle.

The original study didn’t measure muscle strength or performance, but larger, longer, and better (i.e., placebo-controlled) studies subsequently did and found zero benefit. A meta-analysis of studies of growth hormone for athletic performance found that it may even worsen exercise capacity. Wait, how can you gain pounds of lean mass, but not get any stronger? By retaining pounds of water. The lean mass was mostly just due to fluid retention. In fact, obvious swelling (soft tissue edema) is one of the most common side effects of growth hormone, affecting about half of recipients. Other side effects include joint aches, carpal tunnel syndrome, male breast development, elevated blood sugars, and new-onset diabetes.

All this with no evidence of anti-aging effects. If anything, growth hormone may actually accelerate the aging process. For example, those with acromegaly, a disease of excess growth hormone, suffer disproportionately from muscle weakness, as well as diabetes, high blood pressure, artery dysfunction, and bone loss.

In the 1980s, doctors and parents conspired to inject short kids with growth hormone to try to make them grow taller. What happened to them? A study following thousands of children who were injected decades ago with growth hormone for one reason or another found they had a 33 percent increased risk of being dead, largely from brain bleeds and tumors. The strokes would make sense from blood pressure elevation and the malignancies from the growth hormone-induced rise of the cancer-promoting growth hormone IGF-1.

Twenty to thirty thousand people in the U.S. are estimated to use growth hormone in a vain attempt to combat aging, a practice referred to in a leading endocrinology journal as a “medical fraud of unprecedented proportions.” Given the adverse effects, maybe it’s good that all the tested samples of human growth hormone (also known as somatotropin) sourced from online pharmacies were found to have a fraction of the labelled amount (presumably due to degradation from improper storage), and the majority of samples confiscated in another study were counterfeit and contained none at all.

There’s also a proliferation of pills and nasal or sublingual spray forms that makes no biological sense, as the hormone is too large a protein to effectively cross membranes, and, if swallowed, is simply destroyed in the stomach. Given the risk of cancer and potential for a shortened lifespan, one prominent clinician remarked that maybe growth hormone is a “true anti-aging drug” in that it may prematurely stop you from growing any older.

In our next story, we look at how DHEA levels naturally decline with age. So, does replenishing youthful levels have restorative effects?

Dehydroepiandrosterone (DHEA) is the most abundant steroid hormone circulating in the blood, or rather prohormone. It is produced largely by the adrenal glands, and is then converted locally in tissues into androgens (male sex hormones) or estrogens (female sex hormones). DHEA production in the body peaks between the ages of 25 to 35, and then gradually starts to decline about 2 percent every year. By one’s 80s, DHEA production is down about 80 percent 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 the stuff. But U.S. DHEA sales grew to more than $50 million a year on the premise that replenishing youthful levels might have restorative effects.

Given the Premarin debacle with estrogen replacement showing that the reversing of age-related hormonal decline can sometimes do more harm than good, clinical trials were desperately needed. But because DHEA can’t be patented, there has 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 “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 in postmenopausal 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 a 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 IGF-1. 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 percent 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 Lactovegetarian Diet…” After just five days on an egg-free vegetarian diet, blood levels of the DHEA precursor rose nearly 20 percent. 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 percent. 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.