That is a complex question.

There are some supplements that only help while they are being taken in proper doses. This would be things like noortropics. This would be the racetams, Lion's Mane, and a myriad of others that are widely promoted as 'must haves' for proper brain performance.

When looking at the research into noortropics, some appear to have an effect similar to caffeine, maybe without some of the negatives of caffeine.

There are the vitamins and supplements like the B's, D-3, and magnesium, calcium, phosphorus, selenium, etc.

These have two purposes. In the acute stage, they help restore the brain to proper chemical balance so it can do its best healing. Some are needed for specific tasks like B-12, folate and a good balance of the other B's so nerve fiber and the myelin sheath can repair. It is not uncommon for people to get injections of B-12 to help with stress related problems.

Once that repair has maximized, those supplements can help the brain tolerate stress to minimize relapses. One can stop the supplements and try to maintain good brain nutrition with a good diet but a high stress event may need a return to supplements.

The anti-oxidants, E and C primarily, help the cells combat oxidative stress that increases during injury and recovery. They do not have a direct impact but rather a general impact.

Omega 3 oil with a proper concentration of DHA and EPA help with a variety of issues including supporting cellular repair and inflammation. They are valuable at higher doses during recovery but are worth taking as a lifestyle because they help with many other health issues.

The common multi-vitamins have shown to have little value for people who eat a well balanced diet. Unfortunately, most do not. So, a good multi-vitamin can be good at providing many of the trace elements the body needs to function properly. If the body has proper nutrition, it does not tax the recovery needs of the brain.