Four supplements actually work
The shelf has hundreds. The research backs a handful. Here is what is proven, what is marketing, and the doses that matter.
Published
The supplement industry sells hundreds of products to lifters. The evidence supports four, and one of them is food in a tub.
This is not a cynical take — it is what happens when you sort the shelf by strength of evidence rather than by how confidently it is advertised. The genuinely useful list is short, cheap, and has barely changed in twenty years.
3–5 g
Creatine monohydrate — the only real must
0
BCAAs needed, if your protein intake is fine
Evidence against hype
The interesting thing about the supplement market is that evidence and marketing volume are almost uncorrelated. Some of the loudest products have the least behind them; the single best-supported compound is also one of the cheapest.
Evidence vs hype
Where your money actually goes.
How hyped ↑ · Strength of evidence →
Loud · all noise
- Test boosters
- BCAAs
- Glutamine
Loud · and worth it
- Creatine monohydrate
- Protein powder
- Citrulline — modest
Quiet · and unproven
- HMB — in trained lifters
Quiet · and worth it
- Caffeine
- Beta-alanine — narrow use
The shortlist
Dose · effect · verdict
The whole stack, in four lines.
Everything else is either unproven or already covered by your diet.
3–5 g daily
Creatine monohydrate
Roughly +8% strength and +14% lifting volume across the meta-analytic literature. The most studied sports supplement there is.
To hit 1.6 g/kg
Protein powder
Not magic — convenience. Worth buying only if food alone leaves you short of your daily target.
3–6 mg/kg pre
Caffeine
Strength, sprint performance, endurance and focus. Take it 45–60 minutes before training.
3.2–6.4 g daily
Beta-alanine
Helps sustained efforts in the 1–4 minute range. Largely irrelevant to sets of eight.
Creatine, in more detail
If you take one thing, take this. It is the most-studied supplement in sport, it works in the majority of people, and the mechanism is well understood: more phosphocreatine in the muscle means more rapid ATP regeneration, which means an extra rep or two on heavy sets, which compounds into more total training volume over months.
Mono
Only creatine monohydrate has the evidence behind it. HCl, buffered, liquid, "micronised ultra" — those are packaging decisions, not pharmacological ones, sold at three times the price.
A few things worth knowing:
- Skip the loading phase. 20 g a day for a week fills the muscle faster and reliably upsets some people's stomachs. 3–5 g a day gets you to the same saturation in three to four weeks and you were not in a hurry.
- Timing is irrelevant. Saturation is what matters, not proximity to the session. Take it whenever you will remember.
- The weight gain is water, and it is intramuscular. Expect one to two kilos in the first month. It is inside the muscle, not under the skin.
- It does not damage healthy kidneys. This has been examined repeatedly and specifically. It does raise serum creatinine, which is a marker of kidney function — so tell your doctor you take it before anyone reads your bloodwork with alarm.
- Some people are non-responders. Roughly 20–30%, usually those whose diets are already high in red meat and fish and whose muscles are near saturation anyway.
The ones to stop buying
BCAAs. The logic — branched-chain amino acids trigger muscle protein synthesis — is true and irrelevant. If you are hitting your protein target, you are already getting far more BCAAs than any scoop provides, and three amino acids without the other six cannot build anything. They are, quite literally, an incomplete version of what you already ate.
Test boosters. Tribulus, D-aspartic acid, fenugreek and the rest have been tested repeatedly in men with normal testosterone. They do not raise it meaningfully, and the handful that shift a number do not shift strength or body composition. If you genuinely suspect low testosterone, that is a blood test and a doctor, not a tub.
Glutamine. Well supported in clinical settings — burn patients, severe illness. In healthy lifters eating enough protein, it does nothing measurable.
HMB. The early results in untrained subjects were dramatic and have not replicated in trained lifters. Treat it as unproven for anyone reading this.
Third-party testing, briefly
Supplements are regulated loosely almost everywhere. Contamination is real and occasionally consequential — for a tested athlete, a contaminated product ends a career. Look for Informed Sport or NSF Certified for Sport on the label. It costs a little more and it is the only part of the label that is externally verified.
The short version
Creatine monohydrate, 3–5 g a day, forever. Protein powder if food leaves you short. Caffeine before training if you like it. Everything else is optional at best.
Then spend the money you saved on food and sleep, both of which outperform the entire supplement aisle combined.