The Truth About Supplements: What Actually Works for Muscle Growth
TL;DR: Creatine monohydrate has strong evidence for repeated high-intensity performance and training adaptations. Protein powder is a convenient food source, not a requirement. Caffeine can help some forms of performance but also causes dose-dependent side effects. Start with food, then judge any supplement by your goal, health, and the quality of evidence.
Worth it
- Creatine monohydrate: A maintenance dose of 3–5g daily is commonly studied and can improve high-intensity exercise capacity and resistance-training adaptations.
- Protein powder: A convenient way to meet an appropriate daily protein target when food alone is impractical.
- Caffeine: Doses around 3–6 mg/kg can improve performance for many—but not all—people. Lower doses may work, while higher doses raise the risk of insomnia, anxiety, palpitations, and other side effects.
Maybe
- Beta-alanine may help repeated high-intensity efforts lasting roughly one to several minutes. Evidence for citrulline products and many multi-ingredient pre-workouts is less consistent.
Skip
- Products built around proprietary blends or sweeping “test booster” and “muscle builder” claims without transparent dosing and credible evidence.
Safety boundary: Supplements can interact with medicines and medical conditions, and the FDA does not approve dietary supplements for safety and effectiveness before sale. Discuss them with a physician or sports dietitian if you are pregnant, under 18, have a health condition, take medication, or compete under anti-doping rules. Prefer products independently tested for identity and contaminants.
Sources
- Kreider RB, et al. International Society of Sports Nutrition position stand: safety and efficacy of creatine supplementation in exercise, sport, and medicine. J Int Soc Sports Nutr. 2017;14:18. PMC
- Guest NS, et al. International society of sports nutrition position stand: caffeine and exercise performance. J Int Soc Sports Nutr. 2021;18:1. PubMed
- Maughan RJ, et al. IOC consensus statement: dietary supplements and the high-performance athlete. Br J Sports Med. 2018;52:439–455. PubMed
- U.S. Food and Drug Administration. FDA 101: Dietary Supplements. FDA
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