What is the most commonly cited side effect of creatine supplementation?

Weight gain is often highlighted as the most commonly cited side effect of creatine supplementation due to the mechanism through which creatine works in the body. When creatine is ingested, it increases the availability of phosphocreatine in the muscles, which enhances the capacity for energy production during high-intensity exercise. This leads to improved performance and, often, an increase in muscle mass.

The weight gain associated with creatine supplementation can occur for a couple of reasons. First, creatine draws water into the muscle cells, leading to an increase in water weight. This initial gain is usually seen within the first week of use. Additionally, as individuals engage in more intense workouts and potentially increase their training volume or intensity, there may be an increase in muscle mass over time due to enhanced recovery and protein synthesis.

In contrast, while other listed side effects such as headaches, muscle cramps, and fatigue can occur, they are less commonly reported than weight gain. Many individuals experience the water retention and muscle mass increase as a direct result of creatine's function, reinforcing why weight gain is the primary concern cited by users.