Foods to Fight Fatigue (cont.)

Many processed carbohydrates such as white rice, white bread, and pasta contain little or no fiber, thus expending energy at a rapid rate. To ensure you have a food rich in fiber, check the label. A slice of bread should contain 2 to 3 grams of fiber.

Fat Force

Fat has also gotten a bad reputation, and for good reason. Too much of the "bad" fats is associated with heart disease, some types of cancer, and some chronic illnesses. In the right amount, however, fat can make food taste good, and is a concentrated source of energy.

In order to strike the right balance, choose polyunsaturated fats such as vegetable oils and seafood, and monounsaturated fats such as olive oil, meat, and poultry. The unsaturated variety can help lower "bad" LDL cholesterol.

Protein Power

Fats and carbohydrates may supply the body with energy, but protein helps regulate the release of that power. Protein maintains cells, transports hormones and vitamins, and creates muscle. Muscles and many hormones are, in fact, made up of protein. So replenishing the body's source of the nutrient is very important.

"[Water] helps control body temperature through sweat, moves food through the intestines, and greases the joints."

Good sources of protein include meat, poultry, fish, eggs, beans, nuts, and low-fat dairy products.

In diets where the body does not get its usual fuel of carbohydrates and fat, protein provides the body with energy. Preliminary studies have shown that people with high-protein diets appear to be able to work longer and harder, says Finley.

Such findings, however, are controversial. Critics say high-protein diets will ultimately make people more tired and gain weight. There are also concerns the diets may increase the risk of kidney stones and osteoporosis, and be harmful to those with liver or kidney disease.

The Weight of Water

Two-thirds of the human body is made up of water. Without it, we could only live a few days. The fluid helps control body temperature through sweat, moves food through the intestines, and greases the joints. It is also an essential ingredient in the production of energy molecules.

"Dehydration is one of the leading causes of a lack of energy," says Grotto. If you're not well hydrated, your body puts its resources into maintaining your water balance instead of into giving you energy.

Everyone's water needs vary. In February 2004, the Institute of Medicine released a report indicating most people meet their daily hydration needs by using thirst as their guide. In general, the Institute's expert panel recommended that women get about 11 cups of water from food and drink each day, and men get about 16 cups daily. This may seem like a lot of liquid, but 80% of it usually comes from drinking water and other beverages. The other 20% comes from food.

To adequately get your hydration needs, particularly on a hot and humid day, the American Dietetic Association suggests carrying around a bottle of water, or replacing your afternoon soft drink with water. Frozen juice bars or icy treats are also a good idea.

Water is especially important after exercise, with certain medicines, and with a high-fiber diet. Your fluid intake should be adjusted to how much water you're losing, says Finley. "Simple things like stopping at a drinking fountain when you walk by one is a good idea."

Caffeine Fix

More than half of Americans reach for a coffee cup every day, and 25% drink it occasionally, reports the National Coffee Association. This should come as no surprise, as there are those who swear they cannot function without the caffeine.

The compound can be found not only in coffee, but in tea, soft drinks, chocolate, and herbs as well.

John Allred, PhD, a food science communicator for the Institute of Food Technologists, says stimulants like caffeine exaggerate the effect of natural hormones like adrenaline. "They get your heart pumping faster, you respire faster, and that gives you a stimulated feeling," he says, noting the results usually last no more than two hours.

Psychology tests have shown a combination of caffeine and sugar can improve alertness and performance. "But then it wears off, and then you get a little bit of a slump afterward," says Camire. The high-low effect of caffeine, she says, is not as pronounced as it is in sugar, but is significant enough in that frequent users often experience headaches without the substance.

The chemical is, indeed, so potent a stimulant that the National Collegiate Athletic Association (NCAA) lists caffeine as one of its banned drugs, as long as the concentration in a urine sample exceeds 15 micrograms per milliliter. (Two cups of black coffee will produce urine levels of approximately 3 to 5 micrograms per milliliter, according to the National Center for Drug Free Sport.)

The effect of caffeine varies from person to person. Some people need a few cups before experiencing stimulation, while others feel shaky or jittery with one serving.

Caffeine can also interfere with sleep, particularly if it is consumed in the late afternoon. The lack of shuteye could obviously affect one's energy level. To resolve this issue, Camire recommends switching to decaffeinated beverages by about 3 p.m. She also suggests gradually cutting back on caffeinated drinks, especially since they may have a dehydrating effect.

Beating the Doldrums

Food can, indeed, raise or diminish the body's energy levels. If you are eating healthy and are still tired, try changing the frequency of your meals. Some people find they get more of a boost with several small meals throughout the day, while others prefer the dining concept of three square meals daily. There's no right or wrong way, says Sandquist, noting that everyone's energy needs differ.

The amount of food you eat can also make a difference. If someone overeats constantly, they tend to gain more weight and become lethargic, says Finley. "It's like the snowball rolling down the hill," he explains. "As [overeaters] get more overweight, they have less energy, and then they exercise less and don't burn the calories."

Other dietary reasons for fatigue include too much alcohol (which is a depressant) and lack of certain vitamins and minerals. Low iron is a common problem for women.