Don't be a fathead

Men's Fitness, Sept, 2001

More reasons to eat five meals (or 17 snacks) a day

Eating too much fat doesn't just thicken your waist--it may harm your ability to think as well. According to research conducted on rats at the University of Toronto, a diet consisting of 40 percent fat can reduce a number of cognitive functions, including memory, spatial awareness and rule learning. Saturated fat, the kind from meat and dairy products, made the impairment even worse. Researchers speculate that humans would react similarly, probably because fat clogs arteries--reducing the flow of blood to the brain--and may also impede the metabolism of glucose, a form of sugar the brain uses as food.

The upshot? We don't mean to sound like your harping mother, but if you want to stay mentally keen, cut out the burgers and fries, switch to lean meats and low-fat dairy products as well as other healthful protein sources (such as skinless chicken breasts), and increase your intake of fish, beans and fiber-rich foods.