The Four Supplements With Actual Evidence (And the Twenty Without)
A short list of things that hold up, an honest account of what each does and how much it is worth, and a much longer list of things sold with confidence and very little data behind them.
- Creatine, caffeine, beta-alanine and nitrate are the four with the strongest support.
- Protein powder is food, not a supplement. Useful, but it is not doing anything magic.
- Every one of these is worth less than sleep, food and consistent training.
- The effect sizes are small. Small is not zero, but it is small.
- Third-party testing matters if you compete in a tested sport.
The supplement industry is enormous, the evidence base is not, and the gap between the two is filled with confident marketing.
Here is the short list that survives scrutiny, what each actually does, and a longer list of things you can stop buying.
One framing point first. Every supplement below produces a small effect. Small is not nothing — at the margins of performance small matters — but all of them together are worth less than sleeping properly and eating enough. If your sleep is six hours and your protein intake is a guess, no powder is your limiting factor.
The four
1. Creatine monohydrate
The strongest evidence of anything in the category, by a distance.
What it does: increases phosphocreatine stores in muscle, which improves your capacity for short, high-intensity efforts and repeated efforts with incomplete recovery. Over time this supports greater training volume, and therefore greater adaptation.
Dose: 3 to 5 g daily. Every day, timing irrelevant. Loading protocols work faster but are unnecessary — you reach the same saturation in about a month either way.
Form: monohydrate. The expensive variants have never convincingly beaten it.
Who it helps: anyone doing strength work or repeated high-intensity efforts. Less relevant for steady endurance, and the small associated water weight gain is a genuine consideration if you race long — the fuller treatment is in creatine: what it does and what it doesn't.
2. Caffeine
Broad, reliable, and cheap.
What it does: reduces perceived effort centrally, which improves performance across endurance, strength and repeated sprints. Genuinely one of the few things that helps almost everything.
Dose: 3 to 6 mg/kg bodyweight, 45 to 60 minutes before.
The catch: its half-life is long enough that afternoon doses degrade your sleep, and sleep is worth more than the session. Details and the timing rules are in caffeine for athletes.
3. Beta-alanine
Narrower, but real within its window.
What it does: raises muscle carnosine, which buffers the acidity accumulating during sustained high-intensity work. The benefit shows up specifically for efforts lasting roughly one to ten minutes.
Dose: 3 to 6 g daily, split into smaller doses to reduce the tingling. It requires weeks of daily loading — it does nothing if taken acutely before a session, which is exactly how most pre-workouts contain it.
The tingling (paraesthesia) is harmless and dose-dependent. Split doses reduce it.
Who it helps: rowers, 800m–3000m runners, HYROX athletes on station efforts, anyone doing hard intervals in that duration band. Not relevant for a marathon, and not relevant for a heavy triple.
4. Dietary nitrate (beetroot)
Modest, and better supported in recreational athletes than elite ones.
What it does: nitrate converts to nitrite and then nitric oxide, which appears to improve exercise economy — slightly less oxygen consumed at a given workload.
Dose: concentrated beetroot juice providing roughly 6 to 8 mmol of nitrate, taken 2 to 3 hours before an event. Some protocols load for several days beforehand.
Caveats: it turns things an alarming colour, the gut tolerance is variable, and antibacterial mouthwash blocks the conversion because it kills the oral bacteria that perform the first step. Genuinely — do not use mouthwash on race day if you are relying on this.
Who it helps: most reliably recreational endurance athletes. The effect appears smaller in the highly trained.
The honourable mention: protein powder
Protein powder is not really a supplement. It is food in an inconvenient form made convenient.
It does nothing that chicken, dal, eggs, paneer or curd do not. What it does is make hitting a daily protein target easier and cheaper per gram, which for many people is the actual barrier — the practical version of that problem is covered in what 100 g of protein actually looks like.
Buy it if it helps you hit your target. Do not buy it expecting it to do something food does not.
The long list of things that do not hold up
Not all of these are worthless in every context. All of them are sold far past their evidence.
BCAAs. Three amino acids already abundant in any complete protein. If your daily protein is adequate, they are redundant. One of the most successfully marketed unnecessary products ever made.
Glutamine. Extensively studied, consistently unremarkable for healthy athletes.
Testosterone boosters. Almost uniformly ineffective at moving testosterone into any range that matters. The ones that do work are drugs and are sold as such.
Fat burners. Typically caffeine plus stimulants, plus a price. Buy caffeine.
Most pre-workouts. The caffeine does the work. The rest is either underdosed relative to the research or unsupported. You can buy the active ingredient separately for a fraction of the cost and know the dose.
Ketone esters. Interesting research, genuinely unpleasant, and results in performance contexts have been inconsistent. Not a consumer recommendation yet.
Collagen for joints. More promising than most on this list, with some evidence when combined with vitamin C and loading, but nothing like settled. Reasonable to try; do not expect much.
Greens powders. Expensive, and generally not a substitute for vegetables. If you eat no vegetables, eat vegetables.
ZMA, tribulus, deer antler, most "recovery" blends. No.
Multivitamins, for a person eating a varied adequate diet, do very little. Where they help is correcting an actual deficiency — which is an argument for testing rather than for blanket supplementation, as covered in the bloodwork athletes should actually check.
Two practical notes
If you compete in a tested sport, buy third-party tested products. Contamination of supplements with banned substances is a documented and ongoing problem, and "I did not know it was in there" is not a defence. Look for Informed Sport or NSF Certified for Sport.
Vitamin D and iron are different from everything above. They are not performance supplements; they are correctives for deficiencies that are genuinely common in athletes, particularly endurance athletes and those training indoors. The right approach is a blood test, not a guess.
The summary
Creatine if you lift. Caffeine, timed early. Beta-alanine if your events sit between one and ten minutes. Beetroot if you race endurance and want a marginal gain.
That is the list. Total cost, a few hundred rupees a month, and the combined effect is smaller than what you would get from an extra hour of sleep a night.
Which is the actual conclusion of every honest supplement article, and the reason most of them are written by people selling something else.
Questions people ask
Which supplements actually work for athletes?
Four have consistently strong support: creatine monohydrate for strength and repeated high-intensity efforts, caffeine for a broad reduction in perceived effort, beta-alanine for efforts lasting roughly one to ten minutes, and dietary nitrate from beetroot for endurance economy. Everything else is either food, situational, or thinly evidenced.
Does beta alanine work?
For sustained high-intensity efforts in roughly the one-to-ten-minute range, yes — it raises muscle carnosine, which buffers the acidity that builds during those efforts. It requires daily loading over several weeks to work, does nothing acutely, and commonly causes a harmless skin tingling. It is largely irrelevant for long steady endurance work or for maximal strength.
Do beetroot supplements improve endurance?
Dietary nitrate has reasonable evidence for improving exercise economy, meaning slightly less oxygen used at a given intensity. The effect appears more reliable in recreational athletes than in highly trained ones, and it is modest. Typical protocols use concentrated beetroot juice taken two to three hours before an event.
Are BCAAs worth taking?
For almost everyone, no. Branched-chain amino acids are three of the amino acids already present in any complete protein source, and if your total daily protein is adequate you are already getting them in far greater quantity. They are one of the most heavily marketed and least necessary products in the category.
Do you need a pre-workout?
No. Most of what a pre-workout does comes from its caffeine, which you can buy on its own for a fraction of the price and dose precisely. The long ingredient lists largely exist to justify the price, and several common additions are underdosed relative to what the research used.
Keep reading
Creatine: What It Does, What It Doesn't, and Who Shouldn't Bother
The most studied supplement in sport, and still the most misunderstood. What the evidence supports, what it does to endurance athletes specifically, the loading question, and the people for whom it genuinely does nothing.
Alcohol and Training: What One Night Actually Costs
The effects on sleep architecture, protein synthesis, hydration and next-day performance, with the honest magnitudes attached. What a couple of drinks costs versus a heavy night, and how to time it around a training week.
Caffeine for Athletes: Dose, Timing and the Tolerance Problem
One of the few supplements with genuinely strong evidence, and one most people take in a way that blunts it. Effective dosing by bodyweight, timing before a session, whether to cycle off, and what it costs your sleep.