Fuel & Recover · L9
Creatine & the Evidence-Based Shelf
The one supplement that's genuinely worth your money — how it works, how to take it, why it's safe — plus a sort through everything else on the shelf.
The supplement aisle is 95% marketing. You asked for the science on creatine — here it is, with the rest of the shelf sorted honestly. The punchline up front: for your goals, the entire evidence-based stack is basically creatine + enough protein + (optional) caffeine + vitamin D only if you're low. Everything else is situational or noise.
1What creatine actually does
Your muscles store creatine as phosphocreatine, a rechargeable battery for ATP — the fuel for short, hard efforts. During a heavy set, phosphocreatine instantly tops ATP back up, so you can squeeze out roughly one more rep or hold a touch more force.1 That's the whole trick: creatine does not build muscle directly. It lets you train slightly harder, and that extra work, accumulated over months, becomes more muscle and strength.
2How big is the effect — and the "water weight"
Across meta-analyses, adding creatine to resistance training gives about an extra ~1 kg of lean mass and a modest strength bump beyond training alone.15 Real, worthwhile, but an amplifier — not a transformation in a tub.
In the first week you may gain 1–2 kg on the scale. That's water pulled inside your muscle cells (it travels in with the creatine), not under-skin "bloat" and not fat.2 It's part of how it works, and it makes muscles look fuller, not puffier.
3How to take it: just 3–5 g, every day
The goal is to saturate your muscle stores, then keep them topped up. You can rush it or cruise it — both arrive at the same place. Scrub the days:
3–5 g of creatine monohydrate, every single day, forever. No loading needed — it just buys a couple of weeks of speed (and the faster water gain). Timing doesn't matter — pick a time you'll remember. Consistency is the only rule.13
4Buy the boring one: monohydrate
Creatine monohydrate is the most-studied (hundreds of trials), the cheapest, and the reference standard.1 The fancy versions — hydrochloride (HCl), ethyl ester, buffered "Kre-Alkalyn", nitrate — have no proven advantage and cost more. You'd be paying for the label. Plain monohydrate powder is the answer.
5Is it safe? Yes — and the kidney scare is a myth
Creatine is one of the most-studied supplements in existence, with safety shown at up to 30 g/day for five years in healthy and clinical groups.1
Creatine naturally breaks down into creatinine, the very thing kidney blood tests measure — so the number ticks up without any actual kidney damage. Controlled trials show normal kidney function (GFR).4 Two practical notes: if you have pre-existing kidney disease (or you're pregnant), ask your doctor first; and mention you take creatine before any blood test so a raised creatinine isn't misread. The hair-loss rumour rests on one tiny study that never even measured hair.2
6Who benefits most — and a bonus to watch
The lower your starting stores, the bigger the jump — so vegetarians and vegans (creatine comes from meat and fish) often respond most, and older adults get a real anti-ageing benefit for muscle when they pair it with lifting.5 At 40 and beyond, that's squarely in your favour.
Emerging, not settled: creatine may modestly help cognition — especially memory and thinking under stress or sleep deprivation.6 Promising, not a reason on its own, but a nice possible bonus for a busy 40-year-old.
7Sort the shelf
Here's the rest of the aisle. For each one, guess the verdict — Worth it, Situational, or Skip — then see the evidence.
0 / 9 sorted
8Check yourself
What you can now say
- Creatine recharges ATP so you train slightly harder — an amplifier, ~+1 kg lean mass, not a direct builder.
- Take 3–5 g monohydrate daily, forever; loading is optional and timing doesn't matter.
- The early 1–2 kg is intracellular water, not fat or bloat.
- It's safe; the kidney scare is a measurement artefact (tell your doctor you take it before a test).
- The whole worthwhile shelf: creatine + protein + (optional) caffeine + vitamin D if low.
§References
- Kreider et al. (2017). ISSN Position Stand: Creatine, JISSN. PMC5469049.
- Antonio et al. (2021). Common questions & misconceptions about creatine, JISSN. PMC7871530.
- Hultman et al. (1996). Muscle creatine loading in men, J Appl Physiol (loading vs 3 g/day → same plateau). PubMed 8828669.
- “Requiem for creatine-induced kidney failure” (2023) — the kidney-myth review. PMC10054094.
- Chilibeck et al. (2017). Creatine + resistance training, older adults — meta-analysis. PMC5679696.
- Xu et al. (2024). Creatine & cognition — meta-analysis (emerging). PMC11275561.
Lesson L9 of the dad-mod course · all lessons · glossary