Supplements that actually work, and the much longer list that doesn't

The supplement industry is a $160B annual machine optimized to sell you things that mostly don't work. Here's the small list of things that genuinely have evidence, and why most of the rest don't.

The Tier 1 list (real evidence)

1. Creatine monohydrate. Strongest evidence base of any consumer supplement. 5g/day. Helps with strength, muscle gain, and (newer evidence) cognition under stress. Covered in detail in our other post.

2. Vitamin D3. If you're deficient (and a high % of indoor-living adults are), supplementation reliably brings you to normal range. Get a blood test, supplement to target. 1,000–4,000 IU/day is the typical range.

3. Caffeine. Performance benefits well-established. 3–6 mg/kg pre-workout is the studied dose. The 200mg in a typical pre-workout is real, not placebo.

4. Whey protein. Not magic — it's just a convenient protein source. But for hitting protein targets when food is inconvenient, hard to beat.

5. Fish oil (EPA/DHA). Modest cardiovascular and anti-inflammatory benefits, especially if you don't eat fish 2x/week. 1–2 grams of combined EPA+DHA daily.

6. Magnesium glycinate or citrate. If your diet is low in greens, nuts and seeds, supplementation modestly improves sleep and reduces muscle cramps. Not transformative.

7. B12 (for vegans specifically). Mandatory. 50–100 mcg/day or 1,000 mcg 2–3x weekly.

That's most of the list. Eight items. The rest of the supplement aisle is, with rare exceptions, marketing.

The Tier 2 list (situational)

• Iron if blood test shows low ferritin
• Folate during pregnancy or planning
• Probiotics for specific conditions (post-antibiotics, IBS); generic "for gut health" is overhyped
• Beta-alanine for high-rep work in 60–240 second range
• Citrulline for pump and endurance
• Melatonin for occasional sleep disruption (lower doses than typical OTC are usually better)

Things with weak or no evidence

• Most "fat burners" (caffeine + green tea is the only real ingredient; rest is filler)
• Most "testosterone boosters" (do not raise testosterone in clinically meaningful ways for healthy men)
• Most adaptogens (ashwagandha has some evidence; most others don't replicate)
• BCAAs (useless if your daily protein is adequate)
• Most "greens powders" (expensive multivitamin with extra steps)
• "Liver detox" supplements (your liver detoxes itself; this is not a real category)
• Most pre-workouts beyond the caffeine + creatine they contain
• Cold-pressed organic spirulina blue spirulina chlorella anything

The cost benchmark

If a supplement costs more than $1/day for the active ingredient, you're paying for marketing. The Tier 1 list above can be assembled for under $40/month total at quality brands.

A meta-rule

A supplement that works will be:

• Cheap (because it's been off-patent for decades)
• Boring (no flashy marketing required)
• Specific in its claims (not "supports overall wellness")
• Backed by independent meta-analyses, not company-funded studies

If a product is expensive, exciting, and broadly-claiming, it's almost certainly not the breakthrough it markets itself as.

What our app tracks

We have a supplement log in the app for the Tier 1 items. The point isn't to obsess; it's to make sure you're hitting B12 if vegan, magnesium if low-greens, fish oil if low-fish, and so on.

The most useful supplement is one you remember to take. Pick three. Take them daily. Move on.