The Short List of Supplements That Actually Work

The supplement industry runs on hope. Most products on the shelf at your local store have either thin evidence, the wrong dose, or both. Here’s the short list of things with actual studies behind them — what they do, who they help, and what to look for.

1. Creatine monohydrate

The most studied supplement in sports nutrition. Period.

What it does: increases ATP regeneration in fast-twitch muscle. Translates to more reps, slightly more strength, slightly more power output. Also a quietly strong cognitive support (especially under sleep deprivation).

Dose: 5g/day, every day. Skip the “loading phase” — it works either way; loading just gets you to saturation faster.

Form: monohydrate. The fancy versions (HCl, ethyl ester, buffered) cost more and don’t outperform.

Who it helps: every athlete. Vegetarians and vegans especially (their baseline creatine is lower).

2. Whey or plant protein

Not magic — just a convenient way to hit your protein target on busy days. (See the protein article for total intake.)

Look for: 20-30g protein per serving, minimal additives, third-party tested (NSF, Informed Sport).

3. Creatine monohydrate

Yes, on the list twice. That’s how strong the evidence is.

4. Omega-3 (EPA + DHA)

What it does: reduces inflammation, supports cardiovascular health, may aid recovery and joint comfort.

Dose: 2-3g combined EPA+DHA daily.

Look for: triglyceride or re-esterified triglyceride form, third-party tested for oxidation (TOTOX score under 26). Cheap fish oil oxidizes — you don’t want rancid oil.

Who it helps: anyone whose diet doesn’t include 2-3 servings of fatty fish per week. Which is most people.

5. Vitamin D3

What it does: hormone-like role in immune function, bone health, muscle function, mood.

Dose: 2,000-5,000 IU/day. Get bloodwork — target a serum level of 40-60 ng/mL. Don’t megadose without testing.

Pair with: vitamin K2 (MK-7 form, 100-200mcg) for calcium handling.

6. Magnesium

What it does: involved in 300+ enzymatic reactions. Most Americans run low. Helps with sleep quality, muscle relaxation, blood sugar control.

Dose: 300-400mg/day of magnesium glycinate (best for sleep), citrate (best if you’re constipated), or threonate (best for cognition). Skip magnesium oxide — poor absorption.

Take it in the evening.

Electrolytes — the seventh that should be on the list.

Not a “supplement” in the traditional sense, but worth mentioning. On training days, especially in the heat, a quality electrolyte product (sodium, potassium, magnesium, chloride — no sugar required) is one of the highest-ROI additions you can make.

What’s NOT on this list — and why.

• BCAAs: if your daily protein is adequate, BCAAs add nothing.
• Glutamine: weak evidence outside of immunocompromised populations.
• Testosterone boosters: if they actually worked at the dose marketed, they’d be regulated. They’re not. They don’t.
• Pre-workouts: caffeine works. The other ingredients are mostly window dressing. Drink coffee.
• Most pump products: citrulline at the right dose (6-8g) is fine; everything else is hype.

Common questions.

“What about ashwagandha / tart cherry / collagen?” Specific use cases. Ashwagandha for stress/sleep. Tart cherry for recovery from very intense bouts. Collagen for connective tissue when paired with vitamin C. Useful, but not foundational.

“Should I take everything together?” Generally fine, but creatine + electrolytes around training is the strongest combo. Magnesium at night. Vitamin D with a fat-containing meal. Omega-3 with food to avoid burps.

The bottom line.

Six supplements. Maybe seven if you count electrolytes. That’s it. Spend the money you’d waste on the rest on real food, better sleep, or a coach.