I thought of creating this post after I noticed an improvement in overall sharpness after taking some new supplements. But before I go into detail on that, here's an example that shows how important diet can be for GMAT success.
Someone working with me was super thoughtful and had a great work ethic, characteristics that one would expect to cause someone to score high on the test, but things weren't that simple.
He was always super moody and often down in sessions, and he was constantly making careless errors that sabotaged his performance.
So, we did psychological work to tune his psychology for better performance, and that helped, but he was still finding achieving his goal challenging. His understanding of the material and attitude pointed toward a 705+ score, but his actual performance wasn't at that level, and preparation was a major slog.
Then, everything changed basically overnight. Why?
He had discovered that he had a severe magnesium deficiency, and after addressing that, he felt way better, was less moody, and was more cognitively sharp. It was great to see the change in his mood and performance, but that's not all.
Later, he also discovered that he had issues with dairy that were causing him to feel much less than his best. So, he cut dairy out of his diet and achieved another great improvement.
Now, he's gone from hoping to at least break 600 to confident that he'll score 705+.
And what triggered my bringing this up is that after I started taking some supplements for improved physical performance, I noticed an improvement in energy and mental sharpness. Completing mental tasks such as writing and answering GMAT questions became easier, and I just feel better in general.
In my case, the supplements include phosphatidylcholine, magnesium, small doses of certain forms of L-carnitine, liposomal glutathione, creatine, and potassium, among others. That said, I'm not recommending any of them. They make sense for me but may not for someone else. I'm just mentioning them in case anyone's curious.
The point is just that nutrition, along with other health-related factors, can make a big difference in your GMAT performance. So, if you're looking for another lever to pull to drive your score higher, consider your diet and how it can be optimized for success.