Creatine dose by body weight: do I need to scale? Loosely — 0.07 g/kg/day for maintenance, with 5 g being a good universal target.

This guide explains the rationale, gives a precise protocol, and covers the edge cases (timing with food, training, fasting) so you can dose creatine with confidence.

Creatine is a naturally occurring compound synthesized in the liver, kidneys, and pancreas from arginine, glycine, and methionine. About 95% of body creatine resides in skeletal muscle, with the remainder in brain, heart, and other high-energy tissues. Dietary creatine comes primarily from red meat and fish (~1 g/day in omnivores; near-zero in vegans).

Inside cells, creatine is phosphorylated to phosphocreatine (PCr), which serves as a rapid ATP-regeneration system. During short, high-intensity efforts (1–10 seconds), the ATP–PCr system is the dominant energy supplier. Creatine supplementation increases muscle PCr stores by 10–40%, improving repeat-effort performance, strength, and lean mass gains over weeks of consistent training.

Beyond muscle, creatine has well-documented brain effects. The brain uses creatine for cognitive demands and during stress (sleep deprivation, hypoxia, mental fatigue). Vegetarians, vegans, women, and older adults have consistently shown the largest cognitive benefits — likely because their baseline brain creatine is lower. Therapeutic uses are emerging in depression, ADHD, traumatic brain injury, and Parkinson's disease as adjunctive support.