How we grade
- A Strong: many good human trials point the same way.
- B Moderate: decent trials, some mixed results or small effects.
- C Limited: early, small or inconsistent studies.
- D Little to none: the popular claim is not supported yet.
Grades describe the main claim people buy each product for. A strong grade means the research is consistent, not that it is right for you.
The guide
- Creatine A
The most studied sports supplement, with consistent results for strength and power training. - Protein powder A
A convenient way to hit a daily protein target. Total daily protein matters more than the powder itself. - Caffeine A
A well-proven performance aid for endurance, strength and focus, at modest doses. - Beta-alanine B
Raises muscle carnosine and helps most in hard efforts lasting about 1–4 minutes. - Vitamin D B
Essential if you are low. Extra on top of normal levels showed little benefit in a large trial. - Omega-3 (fish oil) B
Important fats found in fish. Supplement results in healthy people are mixed. - Magnesium C
A key mineral that many people under-eat. Extra helps mainly if you are low. - Ashwagandha C
An Ayurvedic herb with small trials on stress and strength training. Promising, but early. - Turmeric and curcumin C
A golden spice central to Indian cooking and Ayurveda. Research on joint comfort is promising but limited. - Electrolytes B
Sodium matters in long, sweaty sessions. For a normal workout, water and food are usually enough. - Collagen C
Research on skin is moderate. Research on tendons and joints is early. - Melatonin B
A sleep-timing hormone. Small effects on falling asleep, with more use for jet lag and shift timing.
No affiliate links, no sponsors. Every page links to its sources so you can read them yourself. Supplements come after sleep, food and training, never before.
Education only, not medical advice. Supplements are not reviewed by the FDA for safety or effectiveness before sale, and nothing here is meant to diagnose, treat, cure or prevent any condition. Talk to your doctor or pharmacist before starting any supplement, especially if you are pregnant, nursing, take medication or have a health condition.