Testosterone boosters: the legal supplement that bans you

There is a supplement you can buy in a shop, legally, off a shelf, that will end your career if it reaches your urine. Nothing about it is hidden. It is printed on the label, in bold, as a selling point.

DHEA.

The sentence that should end the argument

DHEA is prohibited at all times, in and out of competition, under S1 Anabolic Agents on the WADA Prohibited List. Not in competition only. Not above a threshold.

At all times, in the same category as testosterone and nandrolone.

And here is what USADA itself says about why this keeps happening. Because DHEA is accepted by the FDA as a legitimate dietary ingredient, DHEA is by far the most common prohibited anabolic agent found in dietary supplements.

Read that twice. The most common banned anabolic agent in the supplement aisle is a declared ingredient, sold openly, because one regulator calls it food and another calls it a steroid.

How a banned steroid ended up on a shelf

The answer is a piece of American legislation from 1994.

The Dietary Supplement Health and Education Act was written so that people could buy vitamins without a prescription. Through the way it was drafted, substances naturally present in the human body could be sold as supplements. DHEA is naturally present in the human body.

It is produced mainly by the adrenal glands and it is a precursor to both testosterone and oestrogen.

In 2004 the Anabolic Steroid Control Act swept androstenedione and 17 other steroids into controlled-substance status. From January 2005 they could not be sold without a prescription.

DHEA stayed on the shelf.

That single regulatory survival is why, 20 years later, a boxer in Ohio can walk into a shop and buy a prohibited anabolic agent with a loyalty card.

Europe took a different route. DHEA is not an authorised ingredient in food supplements in the EU, where it is treated as a medicinal component rather than a nutrient. There is a centrally registered prescription medicine containing prasterone at 6.5 mg, and in some countries, Germany among them, products supplying 10 mg a day or more are classified as medicines outright. The same product name can therefore be a supplement in one country and a drug in another, and a fighter buying online is buying under whichever rules the seller happens to sit in.

What is actually in a testosterone booster

A published analysis of 50 testosterone booster products sold online across 10 markets found 361 components and 98 distinct ingredients between them.

Ninety-eight ingredients. For one claimed effect.

Of all of them, exactly one appeared on the WADA Prohibited List: DHEA. Declared doses on labels ran 5 mg, 10, 25, 50, and up to 100 mg per serving.

That last number matters more than it looks. DHEA has been registered and used as a medicine at doses in the region of 5 to 25 mg, and lower. A supplement carrying 100 mg is selling several times the upper medicinal dose, without a prescription, without a pharmacist, and without anybody checking what else is in the capsule.

The part that makes it worse

Now the second half, and it is the half nobody selling the product will mention.

There is no good evidence that DHEA increases circulating testosterone, muscle mass, strength or performance in healthy trained men. The theory says it converts to testosterone inside the body. The measured outcomes do not follow.

One review describes its ergogenic potential as largely a myth.

So the arithmetic for a tested athlete reads: real ban risk, no demonstrated benefit.

I have never seen a worse trade offered to a fighter, and it is offered in plain sight, with a barcode.

Tribulus: permitted, and still a bad idea

Tribulus terrestris is the other name that dominates these labels, and it is not on the Prohibited List.

It also does not appear to do what the label says. The human evidence that tribulus meaningfully raises testosterone is weak, and several trials found no significant effect at all.

The real problem is what comes with it. Contamination of tribulus products with prohibited substances, including anabolic steroids and stimulants, is well documented. So you are buying an ingredient with no established effect, in a category with a demonstrated contamination history, while carrying strict liability for whatever ends up in the sample.

An ingredient that does nothing is a waste of money in most aisles. In this one it is a waste of money attached to a risk.

What the laboratories find

The wider picture on this category does not improve on closer inspection.

Across analyses of sports supplements found to be adulterated, testosterone and other anabolic steroids account for the large majority of what turns up. In one analysis of 48 dietary supplements, a whey protein gainer was found to contain nandrolone, testosterone, DHEA, 5-alpha-androstane-3,17-dione and 19-norandrostenedione.

A protein powder.

There is an additional trap in Europe. Products sold under names copied from American prohormones, which were restricted in the United States after 2004, have been found on laboratory testing to contain older-generation anabolic steroids instead. Buyers believed they were purchasing a supplement that had merely been restricted somewhere else.

They were purchasing steroids of unknown origin.

Strict liability applies to all of it. What entered your body is your responsibility, whatever the label said, whatever the shop assistant said, and whatever the manufacturer intended.

The test I give fighters

If a product is marketed on raising testosterone, treat that marketing claim itself as the warning.

A product that genuinely raised testosterone to any meaningful degree would fall under the Prohibited List by definition. So either it does not work, or it works and you are about to fail a test. There is no third outcome that ends well for a tested athlete, and the marketing department is relying on you not to finish that thought.

Names to refuse outright:

• DHEA, including where it is listed as prasterone or 3β-hydroxyandrost-5-en-17-one
• Androstenedione, androstenediol, and any 19-nor variant
• Anything described as a prohormone, in any market, at any price
• Anything sold as a research chemical or marked not for human consumption
• Tribulus terrestris, on the contamination record alone

Check every ingredient on Global DRO before it enters the house, and buy only from a batch-tested certification register.

If your testosterone is genuinely low

Some fighters reading this have a real problem rather than a marketing-induced one. Flat energy, recovery that never arrives, sleep that does not restore, strength going backwards across a camp.

That is a blood test and a doctor, not a tub.

And in combat sports the most common cause is the sport itself, far more often than a hormonal disease. Chronic low energy availability from repeated weight cutting suppresses reproductive hormones as a predictable response to underfuelling, and in documented cases of extreme weight making, testosterone has fallen below clinical reference ranges.

The treatment for that is food and a cut planned further out, not a precursor hormone.

If a doctor does diagnose a genuine deficiency, the route is a therapeutic use exemption, applied for properly and in advance. Testosterone replacement without one is a violation regardless of the medical need, and the exemption route for it is narrow and heavily scrutinised.

The honest summary of this aisle

Most supplement categories contain a mix of things that work, things that do not, and things that are contaminated.

This one is different. The declared active ingredient with the strongest theoretical case is itself a banned anabolic agent, and the evidence it does anything is absent. The rest of the category is 98 ingredients chasing a claim which, if it were ever true, would make the product prohibited for you anyway.

There is no version of this shelf that a tested fighter should be standing in front of.