It has slowly been coming back to me since it's been years that I read it. Last night I realized the issue was a scientist wondering why brains use to be so much smaller or something of that nature. Brains are larger now because of a change in diet from plants to animals. I googled for it and the only place you can get it is from eating meats, seafoods or in supplements, Creatine would be the subject matter at hand, they recommend that vegetarians use a creatine supplement.

https://www.nasw.org/article/eating-meat-drove-evolution-our-big-powerful-brain#:~:text=In%201992%2C%20researchers%20proposed%20that%20this%20gradual%20expansion,from%20muscle%20and%20fat%20stores%20in%20the%20body.