It depends on the supplement, but generally speaking, no. One of the classes I just took was an in-depth look at nutrition which broke it down to a molecular level. It broke my brain a little bit. lol However, the only reason a supplement could work is if you were deficient in something that was contained in it. If you eat a balanced diet, you won't be. With brain health, people tend to look at omega 3 fatty acids, so you get those from things like nuts, seeds, and fish. Those things are all super healthy foods that contain other nutrients your body needs, so it's better to get the omega 3s from them anyway.
Realistically, your body can only use so much of nutrients like these at once and it's really hard to consume too much if you're getting them in your diet. Supplements are different and you can get too much. With this 5,000mg is considered the max safe limit. If you cross it, you might wind up with diarrhea or bleeding problems from excessive supplementation. If you're diabetic, too much can raise your blood sugar too. There are a bunch of side effects. Unless you're deficient in something, a supplement isn't going to help and it could cause harm. Plus, supplements don't have the same manufacturing requirements as medications do, so you never know what you're going to wind up with.
There are lots of nutrition trackers on the market. I'm not sure which ones will monitor your omega 3 intakes, but I'm betting several do. If you're really curious to see whether you're getting enough to support good brain health, you might want to track your diet for a week to find out, and then make small adjustments to your diet to include more if needed. If you're getting 250-500mg per day, your body is getting enough. You get wayyyy more than that eating a piece of salmon or having a handful of walnuts. We're talking the 1,000mg (walnuts) to 4,000mg (salmon) range already. So, if you're already someone who likes fish, supplementation is probably going to push you over the safe limit easily.
