"If stress has effects on the brain and neurological function, then stress has effects on all parts of the body, including the heart, blood vessels, immune system and digestive system," says Dr. Bremner, author of Does Stress Damage the Brain? (Norton). "The long list of damaging effects can include heart disease, memory impairment, depression and even increased susceptibility to stroke and cancer."

A Good Night's Sleep

Although getting a good night's sleep is a basic part of lowering stress and boosting energy, many of us seem to be tossing and turning through an epidemic of insomnia. The fact that so many people appear to suffer from disturbed and unsatisfying sleep may signal not only a personal energy lack, but also a deeper health crisis developing on the horizon. Lack of sleep, along with stress, not only contributes to those lackluster afternoons of the blahs, but it can also derail your basic body rhythms, weaken your immune system and make you age quicker.

Researchers at the University of Chicago report that lack of sleep may deplete your get-up-and-go by upsetting basic metabolic functions and interfering with hormones. Pretty serious stuff: When people in this experiment cut back their sleep time to about four hours each night, their bodies behaved as if they were twenty years older and they started showing signs of developing diabetes. These effects happened in only a week of missing sleep (The Lancet, October 23, 1999).

The drastically reduced sleep schedule slowed the thyroid gland, reducing the production and action of thyroid hormones. As a result, metabolism slowed and the non-sleepers developed that awful sluggish feeling too many of us know and hate.

Stress from lack of sleep also coaxed the adrenal glands into releasing extra amounts of cortisol, a stress hormone whose purpose is to force the body into providing short-lived energy boosts. But after a while the body flames out, its ability to cope with daily demands drained even further.

"We found that the metabolic and endocrine changes resulting from a significant sleep debt mimic many of the hallmarks of aging," says Eve Van Couter, PhD, professor of medicine at the University of Chicago and director of the study. "We suspect that chronic sleep loss may not only hasten the onset but could also increase the severity of age-related ailments such as diabetes, hypertension, obesity and memory loss."

And when are you are constantly short-changed of sleep, it builds up an accumulative effect. Particularly susceptible are busy parents, shift workers, menopausal women and college students.

One way to take back your energy from this metabolic madness is to get twelve hours of sleep a night for a week. But aside from hitting the snooze button a few hundred times, a possible antidote to this cortisol nightmare may be vitamin C.

Fight and Flight

The human body, which evolved before the advent of split-level houses and SUVs, was built to survive life-threatening, physical danger. When it encounters modern-day stress, such as traffic jams and credit card bills, it releases extra cortisol, heightening the body's immediate ability to run or fight. As a result of cortisol release, senses go on high alert, heart rate speeds up, blood flow to muscles increases, and the immune system mobilizes to deal with what it thinks is an imminent crisis.

However, unlike physical danger that rapidly resolves (either you get away from what's trying to harm you or it does you in), today's stress drags on and on (at least till the next exit on the expressway), and the cortisol in the body continues to circulate.

The long-range result of persistent cortisol is a drop in energy, rampant fatigue and lowered immunity. You feel constantly tired and you get sick more often. You may also gain weight.

But researchers at the University of Alabama at Huntsville have found that large doses of vitamin C "reduce...the levels of stress hormones in the blood and also reduce...other typical indicators of physical and emotional stress, such as loss in body weight, enlargement of the adrenal glands, and reduction in the size of the thymus gland and the spleen," according to P. Samuel Campbell, PhD (American Chemical Society, 1999). Dr. Campbell believes that our prehistoric ancestors probably consumed large amounts of vitamin C in a tropical diet rich in fruits. "If so, the physiological constitution we have inherited may require doses far larger than the present RDA (the amount the government recommends) to keep us healthy under varying environmental conditions, including stress."

Iron Out the Fatigue

If you are a premenopausal woman, a lack of iron may also be draining your body of energy. According to experts, as many as one of every five women who menstruate may suffer anemia caused by a lack of iron. This type of problem is also frequent in teenagers and during pregnancy. (But before you take iron supplements, talk to your health practitioner to make sure this is the source of your fatigue.)

"Women with heavy menstrual flow have the greatest risk (of anemia)," points out Susan Lark, MD, in Healing with Vitamins (Rodale). Dr. Lark recommends eating more iron-rich foods (like organic red meat) even if you are not anemic, since a mild iron deficiency can drag you down into the doldrums.

Vegetarians necessarily eat fewer iron-rich foods than do meat eaters. But if you take a vitamin C supplement when you consume such iron-rich vegetables as lima beans, pinto beans and spinach, your body can absorb more of the iron in these foods.

The Krebs Cycle: Keep the Wheel Turning

All of your cells make the energy that keeps you going. This process, a complicated chemical reaction called the Krebs cycle, transforms fatty acids and carbohydrates into ATP (adenosine triphosphate) for cellular energy. Mitochondria, small structures in each cell, are the centers of this energy production.

Energy production requires oxygen. The more oxygen available to the cells, the more energy is produced. Deep breathing and moderate exercise are simple, quick ways to oxygenate the body and boost energy. That is why walking, jogging and other physical activity wakes up your brain and restores pep.

If you've been looking for ways to feel more energetic, take a deep breath and go for a long walk before you sit down to your rejuvenating lima beans and vitamin C. And another thing...take a pass on those late-night TV shows. Sleep is more important.