Gary L. Wenk, PhD, a professor of psychology at Ohio State University and author, discusses how food acts like a drug for your brain in the September 13 online neuroscience section of the original science content magazine Seed.

"The distinction between what is considered a food (something that your body wants or needs in order to function optimally) or a drug (something that your brain wants or needs in order to function optimally) is becoming increasingly difficult to define," explained Wenk.

Here are some gut-brain reactions that might inform your menu planning adapted from Wenk's article.

- Potatoes, tomatoes, and eggplants help with memory formation.
- Fava beans can make you feel a bit better.
- Milk, eggs, cheese, spinach, mushrooms, pumpkin, and various fish and grains can make you feel no pain and trigger "morphine-like chemicals" in the brain.
- Dairy products make babies euphoric.
- Overdoing it with nutmeg could make you hallucinate.

The brain health site recommends eating these six foods regularly to keep your brain fit: wild salmon, minimally processed cacao beans, matcha (green tea powder), acai berries, blueberries and coffee.

For more on gut-brain reactions, you might want to get a copy of Wenk's book Your Brain on Food: How Chemicals Control Your Thoughts and Feelings ($29.95/€23) published in July.