By Erik Strand, published on October 1, 2003 - last reviewed on May 27, 2011
Everyone from time to time experiences fatigue; for some it is an almost daily struggle. It can be a serious drag on your mood.
Broadly speaking, fatigue is simply mental or physical exhaustion. In many ways it is a normal phenomenon, a process that slows the body down at the end of the day and prepares us for sleep, or protects overworked muscles from possible injury. Too often however, fatigue is a negative force in our lives: at best an inconvenience, at worst completely debilitating. Though fatigue is poorly understood, some simple dietary changes can help us keep fatigue from getting us down.
Drink plenty of water. We've all been told a thousand times, but a lot of us still don't get enough. Mild dehydration is a common and often overlooked cause of fatigue. Dehydration can reduce blood flow to organs, slowing down your brain—and you along with it. Drink about eight glasses of water a day, and don't wait until you're thirsty.
Eat breakfast. The brain is fuel-hungry, using up to 30 percent of calories. A good breakfast refills our energy stores, keeping lethargy at bay during the morning hours. This is especially true for children, who have a higher metabolism and smaller energy reserves. Include carbohydrates at breakfast—a whole grain muffin with peanut butter, a piece of fruit and a glass of skim milk.
Eat protein and carbs in combination, especially at lunch. It's not your imagination: that drowsy, dopey feeling you get around 4pm is part of your brain's natural daily rhythms. Dr. Judith Wurtman, a pioneering food researcher at MIT, recommends eating carbohydrates and protein in tandem at lunchtime to fight the afternoon doldrums. Protein contains the amino acid tryptophan, precursor of serotonin, a neurotransmitter that promotes a calm, relaxed feeling, which helps to fight emotional fatigue. Eaten with protein, carbohydrates may boost the brain's intake of tryptophan. Protein-rich foods also contain tyrosine, a precursor to neurotransmitters dopamine and norepinephrine, promoters of alertness, attention, and motivation.
"There's one group of people who are especially susceptible to afternoon fatigue," says Wurtman. "They're called 'women.'" Women often choose skimpy salads for lunch, leaving them at a loss for the nutrients they need. Opt instead for lean protein and unrefined carbohydrates to elevate energy and mood.
Use caffeine judiciously. Caffeinated beverages fight fatigue. Caffeine not only makes you feel more energized, it also increases alertness, reaction speed and ability to think clearly for up to three hours. Harris Lieberman, Ph.D., research psychologist for the U.S. Army, reports that even if you're already rested, a single can of cola can improve vigilance—the ability to pay attention to a boring task. But five or six cups of coffee a day can make you irritable and jittery, actually decreasing performance on some tasks; caffeine late in the day can cause insomnia. If caffeine's your thing, try one cup in the morning and a Diet Coke with lunch.
Get enough calories, but avoid big meals. While overeating is a serious problem for many folks (and can itself lead to fatigue), if you're an intensely active person or you're on a stringent diet, you may not be getting enough calories. Needs vary: take care to consume enough calories for your gender, body type and activity level. High-intensity exercisers need to get enough protein.
Don't, however, take all your calories in one or two daily feasts. Instead, eat five or six smaller meals. A full stomach draws blood to the belly and away from the brain, leaving you listless and dull. Smaller meals also help to keep insulin levels constant, avoiding fluctuations of energy and mood.
Eat iron-rich foods. Iron enables blood to carry oxygen to the organs of the body. Deprived of adequate oxygen, the brain cannot function optimally, leading to lack of mental acuity and feelings of fatigue. Iron intake is not in general a problem for men, but many women have mild iron deficiency. If you suspect you're not getting enough iron, boost your intake with foods like lean red meat, liver, spinach, and apricots.