Everyone knows that what you eat can have a profound effect on the health of your body. We also all know that our brains are a part of our bodies. But yet few of us think much about how our diets affect our mood and thinking beyond slurping a coffee (or five) to keep alert or grabbing a sandwich when hunger makes us cranky.

But according to psychiatrist Drew Ramsey, author of Eat Complete, nutritional deficiencies and dietary mistakes often have a profound effect on his patients' cognition. What you eat really can make your brain work better.

And getting your brain running at its best isn't about switching to a strange, restrictive diet or gorging on some "superfood" whose name you don't even know how to pronounce. Simple changes to your diet that anyone can make will help you be perkier, happier, and even maybe a bit smarter, Ramsey reveals in a thought-provoking recent Big Think video. What are a few items you should pick up at the supermarket today? 

Colorful vegetables

Look down at your plate the next time you sit down for a meal. What do you see? If the answer is some beige chicken next to some beige pasta or potatoes, chances are good you're not getting all the vitamins and nutrients you need for your brain to function at its peak, according to Ramsey. A healthy diet is a colorful diet, he insists.

"You want to look at your plate and see colors. You want to see greens and reds and oranges because each of those colors represent a different phytonutrient, a different pallet of medicine, as it were," he says. So next time you're in the grocery store, toss a few red peppers or leafy greens in your bag to break up all that beige.

Oily fish

"If you think about it, every molecule in your brain starts at the end of your fork," Ramsey reminds viewers. And when it comes to the molecules your brain needs, few are more important than omega-3 fats, particularly one kind called DHA.

"DHA is actually what brain cells are made of," Ramsey points out. Where do you get more of this good stuff? Seafood of all types is good, but small oily fish like sardines and anchovies are the best sources of all. (If those options turn you off, maybe just stick with salmon.)

Cashews and clams

You know an iron deficiency can make you sluggish and dull, but did you know that you don't need lots of red meat to get enough of this key nutrient? If you're not a steak fan, Ramsey points out there are other less well-known sources of iron, like cashews or even clams. And as a bonus, shellfish also apparently contain high concentrations of important brain nutrients like B12 and zinc.

Still have space in your shopping cart? Ramsey offers several other easy and tasty prescriptions in the seven-minute video.