Creatine: biological role and effect on brain function
Creatine is a naturally occurring compound found in meat and fish and synthesized endogenously by the liver, kidneys, and pancreas. It plays a crucial role in energy metabolism, serving as a rapid energy reserve in muscle and brain tissues. Skeletal muscle, which contains about 95% of the body’s creatine, depends on endogenous production or dietary intake for its creatine supply. In contrast, the brain can produce creatine independently due to the presence of key enzymes, i.e., arginine amidinotransferase, and S-adenosyl-l-methionine methyltransferase, in astrocytes, neurons, and oligodendrocytes [10].
Vegetarians, with typically lower dietary creatine intake, show reduced muscle phosphocreatine levels compared to omnivores, yet there are no significant differences in brain phosphocreatine levels between the groups. This suggests that dietary intake does not have a significant impact on brain creatine levels [11]. Creatine gained popularity in the 1990s for enhancing resistance training, particularly in short, high-intensity exercises. Recent evidence suggests that creatine’s benefits extend beyond muscle health, potentially impacting brain function and offering therapeutic roles in neurological and psychiatric conditions, including depression. Although the ergogenic effects of creatine in muscles are well-established, its effects on brain function and optimal dosing strategies are still under investigation [4]. Figure 1 illustrates the overall effects of creatine on brain functions.
