Best and Worst Brain Foods By David Zinczenko, with Matt Goulding

If you want to make the right decisions in confusing times—Time to refinance? Explore a different career? Root for the singing spinster or the 12-year-old?—you need to pay special attention to what you eat. That’s right: Your grocery list can help with your to-do list. That’s because the right foods are a kind of clean-burning fuel for your body’s biggest energy hog: Your brain. A study in the Journal of Physiology makes the point that, though your brain represents only 2 percent of your body weight, it makes 20 percent of the energy demands on your resting metabolism.

On our new Eat This, Not That! Web site, we rounded up the best foods to munch on when you need a mental boost—and found studies that show, in fact, that you can be up to 200 percent more productive if you make the right eating choices. Stock up on these items to halt mental decline, jog your memory, sharpen your senses, improve your performance, activate your feel-good hormones, and protect your quick-witted sharpness, whether you’re 15, 40—or not admitting to any age whatsoever!

FOR SHORT-TERM MEMORY
Drink This!: COFFEE

Fresh-brewed joe is the ultimate brain fuel. Caffeine has been shown to retard the aging process and enhance short-term memory performance. In one study, British researchers found that just one cup of coffee helps improve attention and problem-solving skills.

Not That!: ENERGY DRINKS/TOO MUCH COFFEE

Ever heard of the concept “too much of a good thing”? If you OD on caffeine—too many cups, a jolt of caf from the late afternoon onward, a Red Bull cocktail—it can mess with your shuteye schedule. Sleep is reboot time for your mental computer, and you don’t want to mess with it.

FOR LONG-TERM MEMORY
Eat This!: BLUEBERRIES

Antioxidants in blueberries help protect the brain from free-radical damage and cut your risk of Alzheimer’s and Parkinson’s diseases. They can also improve cognitive processing (translation: thinking). Wild blueberries, if you can find them, have even more brain-boosting antioxidants than the cultivated variety, so book that vacation in Maine now. The berries will ripen in July.

Not That!: THE UNRIPE AND UNREADY

Here’s a cool tip: if your favorite berries are out of season, buy them frozen. The freezer locks in peak flavor and nutrients, so the berries’ antioxidant capacity is maxed out. Those pale, tough, and expensive off-season berries usually ripen on a truck, rather than on the bush, so they’re nutritional imposters compared to the real thing.

For more smart shopping tips, point your grocery cart to THIS story and learn how to pick the most delicious and nutritious while controlling your waistline!

TO THINK FASTER
Eat This!: SALMON OR MACKEREL

If the Internal Revenue Service picks you for some up-close-and-personal auditing, you’ll want to be on your toes when they vet your deductions list. So put salmon or mackerel on the grocery list. The omega-3 fatty acids found in fatty fishes are a primary building block of brain tissue, so they’ll amp up your thinking power. Salmon is also rich in niacin, which can help ward off Alzheimer’s disease and slow the rate of cognitive decline.

Not That!: FULL-FAT ICE CREAM

Not all fats are created equal: Beware foods high in saturated fats, which can clog blood vessels and prevent the flow of nutrients and blood to the brain. Ice cream is not a brain-health food.

TO ENERGIZE:
Eat This!: HIGH-PROTEIN SALAD WITH VINAIGRETTE

The oil in the dressing will help slow down digestion of protein and carbs in the salad, stabilizing blood-sugar levels and keeping energy levels high. Build your salad on a bed of romaine and spinach for an added boost in riboflavin, and add chicken and a hard-boiled egg for more energizing protein.

For other tips on how to build the perfect salad, check out the Eat This, Not That! ultimate salad selector.

Not That!: PANCAKES OR BAGELS

MIT researchers analyzed blood samples from a group of people who had eaten either a high-protein or a high-carbohydrate breakfast. Two hours after eating, the carb eaters had tryptophan levels four times higher than those of the people who had eaten protein. The tryptophan in turkey is one of the reasons you crawl off for an afternoon nap after Thanksgiving dinner. So watch what you gobble.

TO CALM DOWN
Eat This!: LOW-FAT YOGURT OR MIXED NUTS

Scientists in Slovakia gave people 3 grams each of two amino acids—lysine and arginine—or a placebo, and asked them to deliver a speech. Blood measurements of stress hormones revealed that the amino acid-fortified guys were half as anxious during and after the speech as those who took the placebo. Yogurt is one of the best food sources of lysine; nuts pack loads of arginine.

Not That!: SODA

A study from the American Journal of Public Health found that people who drink 2½ cans of soda daily are three times more likely to be depressed and anxious, compared with those who drink fewer. So Mountain Dew is a Mental Don’t.

TO CONCENTRATE
Eat This!: PEPPERMINT TEA

The scent of peppermint helps you focus and boosts performance, according to researchers. Need to reach Chicago before nightfall, and you’re stuck in traffic around Cleveland? One study found that peppermint makes drivers more alert and less anxious.

Not That!: CANDY

Sugary foods incite sudden surges of glucose that, in the long term, cause sugar highs and lows, leading to a fuzzy state of mind. So you’ll need to avoid all the attention-busting sugar bombs on this list of the 20 most sugar-packed foods in America.

FOR GOOD MOODS AND GRINS
Eat This! ARUGULA OR SPINACH SALAD

Leafy greens—arugula, chard, spinach—are rich sources of B vitamins, which are key components on the assembly line that manufactures feel-good hormones such as serotonin, dopamine, and norepinephrine. According to a study published in the Journal of Neuroscience Nursing, a lack of B6 can cause nervousness, irritability, and even depression.

Not That!: WHITE CHOCOLATE

White chocolate isn’t chocolate at all, since it contains no cocoa solids. So it won’t stimulate the euphoria-inducing mood boosters like serotonin, as real chocolate does. Grab the real thing, the darker the better. More cacao means more happy chemicals and less sugar, which will eventually pull you down.

FOR SHARPER SENSES
Eat This!: 1 TBSP OF GROUND FLAXSEED DAILY

Flax is the best source of alphalinoleic, or ALA—a healthy fat that improves the workings of the cerebral cortex, the area of the brain that processes sensory information, including that of pleasure. To meet your quota, sprinkle it on salads or mix it into a smoothie or shake.