Which Supplements Actually Work?

Short Answer

Creatine, vitamin D (if deficient), omega-3s, and caffeine have the strongest evidence. Most other supplements have weaker or more conditional evidence.

**Most supplements are overhyped. A few actually have solid evidence behind them.** Here's our honest tier list based on research quality, not marketing.

Tier 1: Strong Evidence (These Work)

Creatine Monohydrate - Hundreds of studies confirming strength and power benefits - 5-15% improvements in performance - Also benefits brain function, especially vegetarians - Dose: 3-5g daily

Vitamin D (if deficient) - 42% of Americans are deficient - Proven effects on bone health, immune function, mood - Must be deficient to benefit meaningfully - Dose: 2,000-5,000 IU daily

Omega-3s (EPA/DHA) - Reduces triglycerides 15-30% - Anti-inflammatory effects well-documented - Cardiovascular benefits at higher doses (2-4g) - Dose: 1-4g EPA/DHA daily

Caffeine (for performance) - Improves endurance, strength, power by 2-5% - Reduces perceived exertion - Works acutely, tolerance develops - Dose: 3-6mg/kg bodyweight

Tier 2: Good Evidence (Conditional)

Magnesium - Works if deficient (48% of Americans). Helps sleep, stress, blood pressure.

Collagen - Multiple trials show skin and joint benefits. 10-15g daily.

Melatonin - Effective for sleep onset, jet lag. Not a sedative.

Probiotics - Strain-specific. Good for certain conditions (antibiotics, IBS). Not "general health."

Ashwagandha - Reduces cortisol 14-28% in studies. Takes weeks.

Beta-Alanine - For high-intensity efforts 1-10 minutes. Tingles are harmless.

Berberine - Comparable to metformin for blood sugar. Serious drug interactions.

Tier 3: Promising But Limited

NMN/NR - Raises NAD+ levels. Animal data is exciting. Human longevity data doesn't exist yet.

Resveratrol - Works in cells and some animals. Human results inconsistent.

Turmeric/Curcumin - Anti-inflammatory in studies. Bioavailability is poor unless enhanced.

Lion's Mane - Some cognitive benefits in small trials. Needs more research.

Adaptogens generally - Traditional use is long. Modern research is thin.

Tier 4: Mostly Hype

Most testosterone boosters - Don't meaningfully raise T in healthy men.

Most "fat burners" - Caffeine works. Everything else is marginal at best.

Most nootropic stacks - Underdosed ingredients, proprietary blends, big claims.

Biotin (for healthy adults) - Only works if deficient. Most hair/skin claims are marketing.

Detox supplements - Your liver and kidneys already detox. These don't do anything.

Most anti-aging supplements - Based on cell studies or animal models, not human lifespan data.

The Bottom Line

A few supplements have real evidence. Most don't. Stick to the proven ones (creatine, D, omega-3s, magnesium) and be skeptical of everything else.

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