Creatine can improve memory & cognition.

Creatine has benefits that go beyond building muscle or increasing strength / power output. It can also help with short term memory and intelligence / reasoning. There have been a few studies (see here and here) that have demonstrated this. The latter study demonstrated a greater benefit in people over 65 years old and some of the randomized trials note a larger benefit in vegetarians v those who eat meat.

How much creatine and for how long to see a cognitive benefit? All the randomized trials use 5-20 grams of creatine per day and supplemented for at least 2 weeks to see a benefit. Most used 5-10 grams per day. You will not see a benefit if you simply take creatine for one day. It takes time to ‘load’ up you cells with creatine and then it has to be replenished once it is used.

How does creatine help with memory and cognition? Its not completely clear, but it is likely related to improved cellular energy production. Essentially, creatine helps with cycling energy in the form of ATP. This is why you need to continue to take it daily.

Creatine is very safe, we already have it every cell, we get in by consuming meat and there is essentially no know toxic level for it.