Stress & nutrition.

The phone is ringing, the baby is crying, and smoke circles from the oven. Or pink slips are spotted at work, the transmission is slipping, the neighbor's leaves are in your yard (again). Can you identify with any of these? At such times does reaching for the "stress vitamins" help?

Stress results in a cascade of hormones that in turn trigger a cascade of metabolic responses. The body's ability to survive major stress then depends on the status of the endocrine system (hormones) and the nutrient stores to support the metabolic responses.

The natural response to stress is the fight-or-flight response--the means within us to supply the fuel, or energy, needed to stay and fight or get up and run. Hormones increase the blood flow to the liver, causing it to increase the breakdown of the body's sugar, fat, and protein stores for the necessary fuel and/or amino acids for tissue repair that might be needed.

Needs during physiological stress.

Fuel is the predominant need for a person under physical stress. This underscores the importance of good nutrient intake and body stores before the stressful event. Many people lose their appetite when stressed, and may fall short in meeting the energy, or nutrient, needs generated by the stress.

The amount of calories (fuel, or energy) needed during various physiological stresses can be calculated by multiplying the calories needed at rest by a stress factor. A registered dietitian first determines the basal energy expenditure (BEE) of the person resting. The BEE is the amount of calories needed to keep all the vital functions of the body going--the heart beating, the lungs moving air, the cells rearranging nutrients for energy, and the liver, the kidneys, the nerves, and all other organs doing their jobs. By far the majority of the calories a person uses every day are spent for these functions; a much smaller amount are used for physical activity. For normal activity, the calories that are needed are 1.2 times the BEE. During times of physiological stress, additional calories are based on the following table.

As the need for calories increases during physiological stress, so does the need for vitamins and minerals. Their role in our bodies is that of supporting actors in the metabolism, or burning, of carbohydrates (sugars and starches), fats, and protein. Vitamins and minerals are also needed in the building and repairing of muscle tissue, and the formation of hormones, enzymes, and active portions of the immune system.

Needs during mental/emotional stress.

The question is Do I need more nutrients because of the stresses of job, home, or school? It is difficult to quantify an extra need for vitamins or minerals. Normal metabolism of carbohydrates, fats, and protein requires only small amounts of vitamins and minerals. Research is lacking that shows that the need for calories or vitamins and minerals is increased with mental and emotional stress.

Choosing foods each day in the recommended amounts supplies sufficient nutrients to provide the body with the energy it needs.

Vitamin and mineral supplements above the recommended daily allowance (RDA) are not needed during times of usual stress. In fact, megadosing or consuming amounts of vitamins and/or minerals greater than the RDA may have adverse effects. Each nutrient taken in isolation or in high amounts affects others. For example, iron and copper compete for absorption from the gastrointestinal tract. Copper wins the competition and is absorbed, while iron accumulates in the colon. Bacteria thrive on the extra iron, and this results in water and mineral loss. Megadoses of vitamin C (1,000 mg./day) decrease the availability of copper and selenium. Again, intricate relationships exist between all the minerals, with an overabundance of one negatively affecting another.

Balanced diet important.

Food from the garden or grocery store can generally meet nutrient needs without the use of supplements. The California Department of Health divides foods into six categories, giving a recommended number of servings to be consumed each day for balanced nutrition. The most servings per day are needed from the fruit and vegetable group (five to nine) and the bread, cereal, and grain group (six to eleven). These two groups provide abundant amounts of the needed vitamins and minerals along with calories from carbohydrates.

Fewer servings per day are needed from the nonfat or low-fat milk products group (two to five) and the very least of all from the protein group (two). The remaining two categories--fats/oils and sweets--add calories to provide for the fuel needs and should be used in moderation, with a teaspoon of sugar, jam, jelly, or honey considered a serving.

Meeting nutrient needs for periods of stress depend on providing good food to build adequate stores. Good nutrition adds to a feeling of well-being at all times. The stresses may seem less stressful to the well-nourished individual whose outlook on life is generally positive.

Mental and emotional stress has little effect, then, on nutrient needs. Ordinary healthy food in appropriate amounts will provide the nutrients needed to meet the frazzled, frantic, and fractured pace of everyday living.

Georgia Hodgkin, Ed.D., R.D., is an assistant professor at the School of Allied Health Professions, Lorna Linda University, Loma Linda, California.

What About Stress Vitamins?

No amount of vitamin or mineral supplements will alleviate the ill effects of stress. In fact, megadosing on certain supplements when stressed can do more harm than good (see "Stress and Nutrition").

When under severe stress, the body tends to decrease its absorption of calcium and increase its excretion. Other nutrients excreted in excess are potassium, zinc, and magnesium. Calcium is found in plentiful supply in milk, fortified soy beverages, or large servings of green vegetables. Potassium is present in many fruits, vegetables, legumes, and nuts. Zinc and magnesium can be supplied by eating whole grains, nuts, and legumes. So when under unusual stress, be sure to eat sufficient amounts of these types of foods.

Some nutritionists speculate that additional vitamin C may be good when under stress since the adrenal glands are involved in physiological stress and they contain large amounts of vitamin C. However, you can easily get enough vitamin C in food. So save your money on the so-called stress vitamins.