The tried-and-true advice for healthful eating also applies to keeping your energy level high: eat a balanced diet that includes a variety of unrefined carbohydrates, proteins, and fats, with an emphasis on vegetables, whole grains, and healthy oils. Taking a daily multivitamin will ensure that you get the vitamins and minerals you need, but taking extra amounts of individual nutrients won't give you more energy. In addition, eating certain types of foods in particular amounts can help prevent fatigue.
Because different kinds of foods are converted to energy at different rates, some — such as candy and other simple sugars — can give you a quick lift, while others — such as whole grains and healthy unsaturated fats — supply the reserves you'll need to draw on throughout the day. But limit the refined sugar and white starches to only occasional treats. While you may get a quick boost, that feeling fades quickly and can leave you depleted and craving more sweets.
Eat small, frequent meals
Where energy is the issue, it's better to eat small meals and snacks every few hours than three large meals a day. This approach can reduce your perception of fatigue because your brain, which has very few energy reserves of its own, needs a steady supply of nutrients. Some people begin feeling sluggish after just a few hours without food. But it doesn't take much to feed your brain. A piece of fruit or a few nuts is adequate.
Smaller is better, especially at lunch
Researchers have observed that the circadian rhythms of people who eat a lot at lunch typically show a more pronounced afternoon slump. The reasons for this are unclear, but it may reflect the increase in blood sugar after eating, which is followed by a slump in energy later.
Avoid crash diets
If you need to lose weight, do so gradually, without skimping on essential nutrients or starving yourself of the calories you need for energy. Poor nutrition and inadequate calorie intake can cause fatigue. A sensible goal is to try to lose a half-pound to a pound per week. You can do this by cutting 250 to 500 calories a day from your usual diet, and exercising for 30 minutes on most days. Don't cut your food intake below 1,200 calories a day (for women) or 1,500 calories a day (for men), except under the supervision of a health professional.
Use caffeine to your advantage
As a stimulant, caffeine can increase or decrease your energy level, depending on when and how much of it you consume. Caffeine does help increase alertness, so having a cup of coffee before going to a meeting or starting on a project can help sharpen your mind. But to get the energizing effects of caffeine, you have to use it judiciously. It can cause insomnia, especially when consumed in large amounts or after 2 p.m. (or noon if you're caffeine sensitive).
For people who drink alcohol, one of the best hedges against the midafternoon slump is to avoid the sedative effects of drinking alcohol at lunch. Similarly, avoid the five o'clock cocktail if you want to have energy in the evening to pursue a hobby or spend time with your family. If you do choose to drink alcohol, do so at a time when you don't mind having your energy wind down. A glass with dinner is a reasonable choice. And stay within the limits of moderation: no more than two drinks a day for men and one for women.
Water is the main component of blood and is essential for carrying nutrients to the cells and taking away waste products. If your body is short on fluids, one of the first signs is a feeling of fatigue. Sports drinks combine water with vitamins, minerals, and electrolytes — substances that help regulate body processes. But these extras won't give you extra energy for ordinary, everyday activities (see box below).
To maintain your energy level during a workout, drink an 8-ounce glass of water before you start and another after you finish. If you'll be exercising continuously for longer than 30 minutes, drink small amounts every 15 to 30 minutes.
Do power bars or energy bars pack an extra energy punch?
It's impossible to walk into a drugstore or supermarket without seeing shelves lined with "power bars" that claim to boost your energy. The manufacturers of such products claim that they're superior to candy bars because they contain an "ideal ratio" of simple to complex carbohydrates, along with protein and fat. However, there's no proof that such an ideal ratio exists.
An Ohio State University study compared the glycemic index of typical energy bars with other sources of carbohydrates. The power bars were no better than a candy bar at providing sustained energy.