Eat well–BTW, for me, never a problem!
On a serious note, and related to "going with your gut instincts", eating an unbalanced diet can create some issues.
I was reminded of this idiom recently by Elizabeth Bernstein's excellent article in the WSJ on the topic of "When to Go With Your Gut." (NOTE: subscription may be required)
Here is the CliffsNotes version.
In short, if you (regularly) overeat or eat too fast bad bacteria impact your gut. In short, bad bacteria in the gut affects the effective and efficient transmission to your brain. You get the idea.
So if your wish is to optimize on your gut instincts, the lesson here is eat well and eat slow. More vegetables and less refined foods (or anything out of a bag as my doctor likes to remind me). It seems to work for achieving mental clarity. Try it. Maybe a new habit for you.