The shelf
rat chow, with the grade on the label.
39 over-the-counter supplements. Each one has its grade and a plain store search. Read the grade first.
How this shelf works
- Nobody pays us. Every link is a plain Amazon search. No affiliate tag. No cut. No sponsor.
- A link is not a recommendation. Plenty of what sells well has thin proof. The stamp tells you which.
- Nobody checks the bottle first. The FDA does not approve supplements before they go on sale. FDA page
- Look for a seal. The USP Verified mark means an independent group tested that the bottle holds what the label says. USP page
- Not on this shelf: peptides, SARMs and prescription drugs. We don't link to anyone who sells those. See Vendor watch for why.
Repair
Collagen + vitamin C
Small human trials, alongside rehab exercise.
Brain support
Choline
An essential nutrient. Extra has not been shown to sharpen thinking.
PS + Bacopa
Bacopa has small attention trials. PS trials disagree.
Saffron
Dozens of small mood trials. People felt better. Clinician ratings did not move.
Magnesium L-threonate
A few small trials, the first run by the maker.
Health and wellness
Gym supplements
Beta-alanine
A small, consistent boost in hard efforts of 30 seconds to 10 minutes.
Taurine
A small endurance effect. The longevity claim is animals only.
Testosterone boosters
Ecdysterone and turkesterone
Trials disagree. Many products contain almost none.
Zinc
Fixes a shortfall. Did not raise testosterone in well-fed men.
Sleep and stress
Longevity
Fat loss and metabolism, other
Berberine
Small drops in cholesterol and blood sugar. Mostly short trials from China.
Skin and hair
Glutathione
Small skin trials. Drips made people sick in 2026.
Gut health
Peppermint oil
Beat placebo for IBS symptoms, with more side effects.
Zinc carnosine
Tiny studies on gut leakiness. No stomach-lining trial.
Digestive enzymes
Less bloating after one very fatty meal, in 18 people.
Keep going
We show what studies found. We never tell you what to take. Supplements can clash with medicines. Check with a doctor or pharmacist first.