Does Creatine Make You Gain Weight? Creatine is a popular supplement used by athletes and fitness enthusiasts to enhance performance and muscle strength. While it is true that creatine can cause weight gain, it is not in the form of fat. Instead, creatine increases water retention within the muscles, leading to an increase in body weight. This weight gain is temporary and typically resolves once creatine supplementation is discontinued. It is important to note that the primary benefit of creatine is improved athletic performance rather than significant fat gain.