Does Dhea Raise Testosterone
7 Supplements Guys Should Never Take
Men who pop supplements to boost testosterone, rev up libido, or even prevent cancer may not be getting what they think they're getting.
A lot of American guys use dietary supplements — an estimated 47 percent — and they're spending a ton of money on them. In 2011, American consumers spent $30 billion on these over-the-counter nutritional items — 42 percent for vitamins and minerals, 17 percent for herbal or botanical supplements, and 12 percent for sports nutrition products.
But these billions are going for stuff that's neither FDA-regulated nor proven to be safe or effective. Supplement makers can say whatever they want about their products as long as they don't claim to prevent, cure, or treat disease. And a man's decision to use supplements may be motivated more by wishful thinking than by hard evidence. Guys who are hopeful that supplements will bulk them up, maybe prevent disease, or, more likely, boost their bedroom performance, should be especially wary of these 7 supplements.
Beta-Carotene and Vitamin A: Dangerous for Smokers
Beta-carotene is an antioxidant responsible for the deep red-orange color found in carrots, sweet potatoes, and cantaloupe. The body converts beta-carotene into vitamin A, a fat-soluble nutrient that protects cells from damage and that we need for eye, immune system, and skin health.
It's a great example of a nutrient that in the 1960s and 1970s was thoroughly investigated in animal studies, and even in some human observational studies that suggested "greater amounts of beta-carotene intake would result in a lower risk of cancer," said Howard D. Sesso, ScD, MPH, an associate professor of medicine at Harvard Medical School in Boston.
However, these trials testing individual beta-carotene supplements – as well as vitamin A – offered "pretty compelling evidence that the potential benefits were not real," said Dr. Sesso. Some studies even suggested an increased risk for lung cancer in people who took them, especially in men who smoke, he added. Toxicity can result from high doses of vitamin A because the body stores rather than gets rid of excess amounts.
"I'm not aware of any real reasons why someone would want to still consider taking these supplements," Sesso said.
Selenium: Higher Prostate Cancer Risk
Selenium is a trace mineral Americans usually get enough of from breads, grains, meat, poultry, and fish. It's another antioxidant that's been evaluated in high doses to see if it could protect against chronic diseases like cancer. However, "the selenium trial that was done years ago in people to prevent recurrence of skin cancer actually increased the recurrence of skin cancer," said Alan Kristal, DrPH, a faculty member in the Public Health Sciences Division at the Fred Hutchinson Cancer Research Center in Seattle.
Further analysis suggested a prostate cancer risk benefit, said Dr. Sesso, which helped propel the launch of the SELECT trial, the largest prostate cancer prevention study to date that tested the effects of selenium and vitamin E. However, SELECT found no benefits in prevention of prostate cancer, said Dr. Kristal, one of the study's authors. And the most recent analysis even showed increased prostate cancer risk in some men.
"There don't appear to be any compelling results or reasons to be taking selenium to prevent prostate cancer, or at least cancer in general, at this time," Sesso advised.
Kristal agrees. "Why would you take selenium if it's not going to help you?"
Vitamin E: No Impact on Heart and Cancer Risk
Vitamin E is a fat-soluble antioxidant found in nuts, seeds, and vegetable oils that's also been studied extensively for disease prevention. Substantial research had "suggested that vitamin E would reduce not just cancer risk, but also cardiovascular disease risk," said Dr. Sesso.
However, as Dr. Kristal explained, vitamin E failed to show benefits in people: "It looked good and it worked in a test tube, but it had absolutely no impact when tested in humans." Sesso agrees. Most of the trials "found that there doesn't appear to be any obvious benefits to taking individual vitamin E supplements."
But research is mixed on the vitamin's effects on prostate cancer. In contrast with the SELECT trial, which found an increased risk for the disease in men who took selenium and vitamin E, the Physicians' Health Study II (PHS-II) "found no effect on prostate cancer at all," said Sesso, one of the authors of PHS-II. "We don't believe that there are any obvious risks for vitamin E supplementation and prostate cancer" if you consider all of the evidence, he explained.
Still, Sesso advises that "there's no reason to take it, either. It's not because of potential risk, but just because of lack of benefit, also."
Yohimbe: A Flop for Erectile Dysfunction
The extract from the bark of yohimbe, an evergreen tree found in western Africa, is sold over-the-counter, but its active ingredient, yohimbine, is available only by prescription. Yohimbe bark supplements claim to help erectile dysfunction (ED), even though "very few studies show that it's very useful," said Keith D. Bloom, MD, a urologist at Baylor Medical Center in Irving, Texas.
According to Dr. Bloom, supplements like yohimbe aim to mimic, to some degree, what Viagra, Cialis, and Levitra do, which is to increase blood flow, but "they just don't do it nearly as well as the prescribed medications do, they don't do it as safely, and they're unregulated," he said.
Another issue is that yohimbe doesn't mix well with some commonly prescribed drugs. "It can interact with other medications that patients may be on for blood pressure," said Bloom. "It may also interact with other stimulants and certain antidepressants." Yohimbe also causes some unpleasant and even risky side effects, including elevated blood pressure, increased heart rate, dizziness, flushing, nausea, and headache.
"There's really no good reason to be taking it at all," Bloom asserted. "I wouldn't recommend it to anyone."
Horny Goat Weed: An ED Aid That May Contain Arsenic
Horny goat weed is a plant whose active ingredient, epimedium, is purported to help ED.
"This weed supposedly earned its name after a shepherd noted increased sexual behavior in goats who had eaten it," said Dr. Bloom. According to the urologist, the supplement is thought to increase blood flow in the penis, but it's never been studied in people.
Because these types of male enhancement products are not FDA-regulated, "you don't know what you're getting, you don't know how much of the supplement you're actually getting, and you don't know what other fillers are being used to formulate the supplement," Bloom cautioned. "Companies aren't required to tell you everything they put into a supplement." Potential problems can include allergic reactions to unidentified ingredients and contamination with dangerous substances like lead and arsenic.
"The most important thing that I would express is that if you have ED, it's best that you see a doctor to rule out more serious health conditions such as heart disease and diabetes," Bloom said. "That's a very, very important takeaway, rather than treating yourself."
DHEA: A Downer for Good Cholesterol
DHEA — short for dehydroepiandrosterone — is a steroid hormone that the body makes and converts into sex hormones. The body's levels decline naturally starting at about age 30. Some men take DHEA supplements containing a synthetic form sourced from soybeans to replace the hormone. Purported benefits include libido- and testosterone-boosting effects.
"DHEA may have some vasodilator qualities, meaning it will increase blood flow, but the main reason people take it is to potentially increase androgen or testosterone-like compounds and estrogen," said Dr. Bloom. "So it's thought that it can increase libido in men and women…but there's no great data on that." Bloom cautioned that with steroidal supplements like DHEA, "there have been quality-control issues with over-the-counter preparations, in terms of how much active ingredient is added."
DHEA supplements can present other risks. "There are side effects with palpitations and worsening of the cholesterol profile," he warned, which means a "lowering of the good cholesterol [or HDL] that you want to be elevated." He's also concerned that the supplements "can suppress your body's potentially normal production of DHEA."
For men still considering DHEA supplements, proceed with caution: They "should not be taken without supervision," advised Bloom.
Tribulus Terrestris and Tongkat Ali: Don't Boost Testosterone
Tribulus terrestris and Tongkat ali are flowering plants that make up two of the more common ingredients found in so-called testosterone-boosting supplements. Not much is known about either plant's effects on testosterone levels. Although Tribulus terrestris"may increase libido in animal studies…the only human studies I found showed it did not increase testosterone," said Dr. Bloom.
"I tell patients who ask about supplements that if they were as effective as they claimed, we would use them routinely," he said. "It would be our standard of care."
Source: https://www.everydayhealth.com/mens-health-pictures/supplements-guys-should-never-take.aspx
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