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Stuart Phillips@mackinprofX

I've seen some misplaced supplement hype in my time as a researcher, but I wonder when we're going to learn that there are NO Testosterone …

what it claims

There are no dietary supplements marketed as 'testosterone boosters' that have a scientific basis demonstrating their efficacy; the only proven method for supporting these levels is the practice of resistance training.

holds up

Stuart Phillips, a recognized researcher in exercise physiology, highlights a reality documented in the scientific literature.

noli's read

Stuart Phillips, a recognized researcher in exercise physiology, highlights a reality documented in the scientific literature. Meta-analyses and systematic reviews of ingredients commonly sold as 'boosters' (such as Tribulus terrestris or fenugreek) consistently show a lack of significant effect on testosterone levels in healthy men. While certain supplements like zinc or vitamin D can prevent a drop in testosterone only in cases of proven deficiency, they do not function as enhancement agents in individuals who are not deficient. Conversely, there is a solid consensus, supported by numerous intervention studies, that resistance training (gym) is a powerful lever for optimizing hormonal profiles and overall metabolic health. The assertion does not seek to deny the existence of testosterone, but to distinguish between baseless marketing products and actual physiological interventions. It is a necessary caveat in the face of an industry that often overinterprets animal data or weak correlations.

the sources

Claimed by Stuart Phillips. Noli grades the claim, never the person.

Decoded by Noli · July 18, 2026 · the original post

Stuart Phillips in the Register42 claims graded · solidity 96/100See their record →

More from Stuart Phillips

Physical activity intensity is a more important driver than quantity for reducing mortality risk and promoting longevity.

holds upStuart Phillips

Rather than fasting to induce autophagy and mitophagy, prioritize physical exercise, which activates these processes more dynamically while promoting the renewal of proteins and organelles.

holds upStuart Phillips

HIIT is not superior to continuous aerobic training (CAT) for fat loss, but it is more effective at improving VO2 max, fasting blood glucose, and total cholesterol.

holds upStuart Phillips

Others on this

The buzz from a Monster Energy comes almost entirely from its caffeine (and the sugar riding along with it) — the taurine and the B-vitamin megadoses on the can don't add a proven benefit beyond that.

mixedscience.snitch

Extreme, prolonged sun deprivation — like months aboard a nuclear submarine — is exactly the scenario where routine vitamin D supplementation makes real sense: several studies on submarine crews (Royal Navy, US Navy) show levels drop markedly within weeks without it.

holds upPaul McNally

For women in their 20s: four basics are enough — omega-3, vitamin D3, magnesium glycinate, and a quality probiotic — rather than 15 supplements.

mixedThebiohackingrn

Noli has read similar claims

Other advice in the Register that leans on the same research.

Dietary supplements labeled as "testosterone boosters" are ineffective for promoting muscle mass gain in healthy individuals.

holds upJeff Nippard

Some supplements (creatine, whey, caffeine, ashwagandha) are genuinely effective and useful, while others (collagen, EAA/BCAA, glutamine, testosterone boosters, fat burners) are largely useless, ineffective, or overrated for muscle gain and performance.

holds upLayne Norton, PhD

For building muscle, only two supplements have solid, consistent evidence — creatine monohydrate (3-5g/day) and protein powder if your food intake is already falling short. Everything else — turkesterone, HMB, testosterone boosters, mass gainers — is either ineffective or only situational, and the placebo effect (believing it works) sometimes outweighs the compound itself.

holds upJeremy Ethier, BKin

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