Creatine is a popular supplement in the fitness world known for its ability to draw more water into muscles and increase power output from muscles. However, recent studies have also shown that creatine supplementation can have positive effects on mood and even treat depression.
The phosphocreatine system in the brain, particularly in the forebrain, has been linked to the regulation of mood and reward pathways as well as depression. Studies have shown that increasing the activity of this system through creatine supplementation can be beneficial in improving mood.
Several double-blind, placebo-controlled studies have been conducted on creatine supplementation for the treatment of major depression. The studies have been done on women, men, and adolescents, some of whom were taking SSRIs, and some of whom were not. The results have shown that creatine supplementation either lowers the required dose of SSRI or improves the effectiveness of a given dose of SSRI.
One of the things that's striking about these studies is that most of them used dosages that are pretty reasonable for most people, anywhere from three grams to five grams, sometimes up to as many as ten grams per day of creatine. Many of these also increased activity in the forebrain phosphocreatine system, and some showed a relationship between this system and the NMDA receptor, a receptor critical for neuroplasticity.
While the details aren't entirely clear, it seems that creatine supplementation leads to increases in the phosphocreatine system in the forebrain, which relate to changes in the way the NMDA receptors function, and may lead to some of the plasticity, the changes in neural circuits that underlie the shift from negative mood and affect to positive mood.
In conclusion, while there are still gaps in the research, it appears that creatine supplementation can have positive effects on physical performance and mood. For most people, a low dose of creatine supplementation, ranging from one gram to five grams per day, can be beneficial. However, people with kidney issues need to be especially cautious. Overall, creatine supplementation is a promising avenue for improving both physical and mental health.