The Worst Foods For Your Brain
Likely sources: Deep-fried treats, the crackers you always have in the house and, of course, fast food.
What they have in common: Artificial trans fats, which are such unequivocal bad news that the FDA told U.S. food manufacturers to get the most common form of them (partially hydrogenated oils) out of their products within the next three years.
Science says: These fats could do a number on your memory. The more trans fatty acids people consumed, the worse they performed on a word-recall test, found a study in PLOS One. High consumption of them is also linked to smaller brain volume and aggression and irritability.
The amount it's okay to eat: Ideally none. So until that three-year compliance period is up, watch out for partially hydrogenated oils on nutrition labels.
Likely sources: Soups, sodas, yogurt and candy, among others.
What they have in common: Added sugar.
Science says: It's bad for your memory, too. A high-sugar diet made it harder for rats to remember where a specific object was located in a place they'd been to before, according to findings published in Brain, Behavior and Immunity. Inflammation was detected in the hippocampus, a crucial area for memory. High amounts of sugar can lead to inflammation in humans brains too, says Jennifer Molano, MD, associate professor of neurology and rehabilitation medicine at the University of Cincinnati, and it may make your brain less efficient at retrieving and processing information.
The amount it's okay to eat: The American Heart Association says women shouldn't go above 6 teaspoons of added sugar per day, which is the roughly the amount you'd get from one candy bar, about ¾ of a can of soda or a 6-ounce container of low-fat vanilla yogurt.
Photo: Cameron Whitman/thinkstock
Likely sources: Your favorite sandwich. Bread, cheese, cured meats and cold cuts and are full of this mineral.
What they have in common: They're high in sodium.
Science says: A study in Neurobiology of Aging tracked the activity levels and sodium intake of more than 1,200 men and women between the ages of 67 and 84 and found that tons of sodium plus little activity led to poorer cognitive health. Interestingly, salt appeared to be more of a problem than couch potato–ness, as adults with low sodium and low activity fared better over time. Just as sodium does in other parts of the body, it can lead to a narrowing of the blood vessels that transport oxygen and other essential nutrients, Molano says, which means your brain can't get the resources it needs to work at its highest levels.
The amount it's okay to eat: What defines "too much" when it comes to sodium is a hotly debated topic, with some experts saying the standard guidelines (no more than 2,300 grams per day for healthy people; 1,500 mg if you're over 50, African-American, or have high blood pressure) are too restrictive. Talk to your doctor about what's best for you.
Likely sources: Dairy, desserts and the chip-and-dip combos you dig into at parties.
What they have in common: They're high in fat.
Science says: The list of healthy fat's benefits continues to grow. But a diet that's too high in total fat may affect your emotions, according to research in the International Journal of Obesity. Mice put on a high-fat diet (58 percent of their calories came from fat) developed signs of despair, anxious behavior and increased levels of a protein that's known to be higher in depressed people (brain-derived neurotropic factor). And saturated fat may be particularly harmful, says study co-author Stephanie Fulton, PhD, associate professor of nutrition at the Montreal Diabetes Research Center at the University of Montreal.
The amount that's okay to eat: Aim to get between 56 and 78 grams of good-for-you mono and polyunsaturated fat per day (think fish, nuts and avocados). Cut off daily saturated fat at 16 grams (the amount you'd get from three slices of cheddar cheese). (Based on a 2,000-calorie-per-day diet).