Vitamins and Minerals for Stress Adaptation
It almost goes without saying that taking a general multivitamin and mineral supplement is a good idea for anybody who is under stress, maintains a hectic lifestyle, or needs more energy. Every energy-related reaction that takes place in the body, especially those involved in the stress response, relies in one way or another on vitamins and minerals as cofactors to make the reactions responsive and effectivego. For example, B-complex vitamins are needed for metabolism of protein and carbohydrate; chromium is involved in utilizinghandling carbohydrates; magnesium and calcium are needed for proper muscle contraction; zinc and copper are required as enzyme cofactors in nearly three hundred separate reactions; iron is needed to help shuttle oxygen through the blood—the list goes on and on.
It is fairly well accepted in the medical community that subclinical or marginal deficiencies of essential micronutrients, especially the B vitamins and magnesium, can lead to psychological and physiological symptoms that are related to stress. One study, published in 2000, looked at the effects of a multivitamin/mineral supplement on overall stress levels. The supplement was a water-soluble formula, composed of vitamins C (1,000 mg), B-1 (15 mg), B-2 (15 mg), B-3 (50 mg), B-6 (10 mg), B-12 (10 mcg), biotin (150 mcg), pantothenic acid (23 mg), calcium (100 mg), and magnesium (100 mg). For a period of thirty days, 150 volunteers, who were prescreened for having high levels of stress, consumed the supplement each morning with water, while another 150 "high-stress" volunteers received a placebo pill. Before and after the thirty-day supplementation period, researchers administered a battery of standardized stress tests. The test results showed a statistically different and clinically important improvement in the overall stress index of the volunteers taking the multivitamin/mineral supplement, but the improvements were not indicated in the placebo group. Another study (also a double-blind, placebo-controlled trial) of eighty healthy male volunteers found that twenty-eight days of treatment with a mineral supplement containing calcium, magnesium, and zinc significantly reduced anxiety and sensations of stress. These studies, and dozens like them, support the rationale behind using a general nutritional supplement as an antistress foundation on which to build a solid cortisol-control regimen.
In an effort to capitalize on the huge market for "stress-reducing" products, many of the large pharmaceutical and dietary-supplement companies have introduced "stress-formula" multivitamin products. These formulations are based on available scientific evidence suggesting that certain nutrients may be needed at levels higher than the RDAs (recommended daily allowances) for optimal support of adrenal function and control of cortisol levels. For example, vitamin C supplementation at a dose of 1,000 mg per day improves the capacity of the adrenals to adapt to surgical stress by normalizing cortisol and ACTH in patients with lung cancer. Thiamin (vitamin B-1) is effective in reducing the typical increase in postsurgical secretion of cortisol from the adrenal glands. In one study, a combination of vitamins C, B-1, and B-6 was able to bring the pattern of cortisol secretion back into normal ranges following surgery. Pantothenic acid (vitamin B-5) is another required nutrient for proper functioning of the adrenal gland. Consumption of pantothenic acid by humans buffers the rise in cortisol during experimental stress, which suggests a potential benefit of vitamin B-5 in controlling the hypersecretion of cortisol during periods of stress. Overall, it makes little difference whether you decide to get your cortisol-controlling nutrients as part of a general multivitamin/mineral product or from a more targeted "stress-tab" sort of formula; the important thing is that you do get them.
Without getting bogged down in too many details, I can outline some of the general ways in which essential nutrients (vitamins and minerals) help to counteract the detrimental health effects of chronic stress. For example, magnesium, a mineral that we most often think about in terms of bone health and heart function, has been shown to reduce cortisol levels following exhaustive exercise in healthy male athletes. Zinc, a mineral that we commonly associate with bone health and immune function, is known to alter adrenal metabolism when levels in the diet are either too high or too low. In one study, 25–50 mg of zinc (about two to three times the RDA) resulted in a significant fall in plasma cortisol levels in healthy volunteers (again, following an extreme exercise stress test that typically raises cortisol levels). Chromium, a mineral that we typically think of in terms of its benefits for blood-sugar control and appetite regulation, has been shown to help reduce serum cortisol in livestock (cattle and sheep) exposed to the stress of cross-country transport. In both groups of animals, those receiving chromium supplements also demonstrated a more robust immune-system function, as evidenced by fewer infections, than the animals receiving the placebo.
In addition to the observed effects of isolated nutrients on cortisol levels, there are numerous instances of general dietary alterations bearing a positive impact on reducing elevated cortisol levels. For example, one study of sodium restriction documented a drop in urinary levels of cortisol following one week on a sodium-restricted diet. Upon switching back to the higher-sodium diet, researchers observed a 30 percent increase in the body's production of cortisol within a few days. Dietary changes in protein and carbohydrate intake are also known to influence the body's handling of cortisol. In one study of athletes, consumption of an amino-acid solution (100 mg arginine, 80 mg ornithine, 70 mg leucine, 35 mg isoleucine, and 35 mg valine) resulted in a significant suppression of cortisol levels within sixty minutes. When it comes to carbohydrate consumption, numerous studies have demonstrated the cortisol-lowering benefits of carbohydrates, especially when they are consumed during exercise. In one notable study, after ten days on a high-carbohydrate diet, cortisol concentrations were significantly lower than after ten days on a lower-carbohydrate diet. Supplementing one's diet with a carbohydrate-rich sports drink has also been shown to reduce serum cortisol during endurance exercise (compared to a placebo drink). High-fat diets, in contrast, have been shown in rodent studies to impair the body's ability to restore normal cortisol levels following stress.
So there you have it—cortisol metabolism, and indeed the entire underlying stress response, is influenced to a large degree by a person's intake of vitamins, minerals, and other nutrients. Knowing this to be true, a big step you can take in controlling your own stress response is to eat right and to take at least a basic multivitamin supplement (or even better, a comprehensive multivitamin/multimineral supplement). For more targeted cortisol-control activity, some nutrients appear to offer additional benefits; these are outlined in the sections that follow.
Vitamin C, also known as ascorbic acid, is a water-soluble vitamin needed by the body for hundreds of vital metabolic reactions. As a dietary supplement, vitamin C is consumed by more people than any other vitamin, mineral, or herbal product. Good food sources of vitamin C include all citrus fruits (oranges, grapefruit, lemons) as well as many other fruits and vegetables, such as strawberries, tomatoes, broccoli, Brussels sprouts, peppers, and cantaloupe.
As a dietary supplement, vitamin C is generally regarded as a potent antioxidant and is typically consumed for the prevention of colds, stimulation of the immune system, promotion of wound healing, and to ward off some of the detrimental effects of stress. Because of the wide variety of reactions in which vitamin C plays a role, many claims are made about its value as a supplement. Perhaps the best-known function of vitamin C is as one of the key nutritional antioxidants, whereby it protects the body from free-radical damage. As a water-soluble vitamin, ascorbic acid performs its antioxidant functions within the aqueous portions of the blood and cells, and it can help restore the antioxidant potential of vitamin E (a fat-soluble antioxidant).
As a preventive against infections such as influenza and other viruses, vitamin C is thought to strengthen cell membranes, thereby preventing entrance of the virus to the interior of the cell. Support of immune-cell function is another key role performed by vitamin C and one that may help fight infections in their early stages. The combined effects of cellular strengthening, collagen synthesis, and antioxidant protection are thought to account for the multifaceted approach by which vitamin C helps to counteract stress and maintain health.
In two separate studies about vitamin C supplementation (1,000–1,500 mg per day for one week), ultramarathon runners showed a 30 percent lower cortisol level in their blood when compared to runners receiving a placebo. In another study of healthy children undergoing treatment with synthetic corticosteroids, 1 gram (1,000 mg) of vitamin C, consumed three times a day for five days, resulted in significantly lower cortisol levels compared to healthy children given a placebo. In a study of lung-cancer patients, a dose of 2 grams of vitamin C, given daily for one week prior to surgery, was able to bring elevated cortisol levels (resulting from the surgery) back to normal ranges in a significantly shorter period of time compared to patients receiving a placebo.
It has been shown in numerous animal and human studies that even a subclinical deficiency of vitamin C (that is, a deficiency small enough not to produce results detectable by the usual clinical tests) will result in an elevation of plasma cortisol levels. In studies of various laboratory and livestock animals, even a marginal vitamin C deficiency produced a significant increase in plasma cortisol levels and an inhibition of immune function, both of which were reversed by adding vitamin C back into the diet. These suboptimal levels of vitamin C, and their resulting elevation in cortisol, may account at least in part for the immune-system suppression and mild depression observed in elderly volunteers. In one study, thirty elderly volunteers (ten women and twenty men) were given 1 gram of vitamin C daily for sixteen weeks. Results showed a significant decrease in serum cortisol in both groups, as well as a significant improvement in various parameters of immune function.
Vitamin C supplements are most often used as a way to prevent or reduce the symptoms associated with the common cold—and well over one hundred studies have been conducted in this area. In several of the largest studies, no effect on common-cold incidence was observed, indicating to many scientists that vitamin C has no preventive effects in normally nourished subjects who experience normal exposure to stress. However, a number of smaller, targeted studies, conducted on subjects under heavy stress, show that vitamin C decreases the incidence of the common cold by more than 50 percent. In other studies, healthy subjects consuming low levels of vitamin C (below 60 mg per day) experienced about one-third fewer colds following vitamin C supplementation.
In most cases, it appears that although the most important and dramatic preventive effects of vitamin C supplementation are experienced by individuals with low vitamin C intakes, those with an average daily consumption from foods may also benefit from supplemental levels—especially during periods of heightened stress. In support of an elevated vitamin C intake, an expert scientific panel recently recommended increasing the current RDA for vitamin C from 60 mg to at least 100–200 mg per day. This same panel also cautioned that taking more than 1,000 mg of vitamin C daily could have adverse effects and recommended that "whenever possible, vitamin C intake should come from fruits and vegetables"—more support for getting at least your "daily five" servings of fruits and vegetables.
Although the Food and Nutrition Board has recently raised the RDA for vitamin C from 60 mg to 75–90 mg (instead of to 100–200 mg per day, as recommended by the expert panel), it is well established that almost everybody can benefit from ingesting even higher levels. For example, the vitamin C recommendation for cigarette smokers is 100–200 mg per day, because smoking destroys vitamin C in the body. You need not worry about developing the vitamin C deficiency disease, scurvy (as long as you consume at least 10 mg of vitamin C daily), but be sure to increase your intake if you're exposed to stress (physical or psychological) or infection (for example, from a sick friend of family member).
In terms of safety, vitamin C is extremely safe even at relatively high doses, because most of the excess is excreted in the urine. At high doses (over 1,000 mg per day), however, some people experience gastrointestinal side effects, such as stomach cramps, nausea, and diarrhea. In addition, vitamin C intakes above 1,000 mg per day may increase the risk of developing kidney stones in some people.
Although vitamin C is well absorbed, the percentage absorbed from supplements decreases with higher dosages; therefore, optimal absorption is achieved by taking several small doses throughout the day. For example, try 100–250 mg per dose for a total daily intake of 250–1,000 mg. Full blood and tissue saturation is typically achieved with intakes of 250–500 mg per day.
Sharon was a high-achieving college student who experienced an extreme degree of anxiety and stress during exams—particularly during midterm and final-exam periods. Like millions of students around the world, Sharon was far more likely to become sick (usually catching a cold or the flu) during exam periods than at other times of the year. During exam periods, the combination of poor diet (lots of junk food), inadequate sleep (late-night study sessions), and heightened anxiety (about grades) led to a cortisol-induced suppression of immune-system function—and a dramatic rise in illness rates for Sharon and her classmates.
To guard against the inevitable increase in cortisol levels and suppression of immune function during midterm-exam week, Sharon supplemented her diet with a cortisol-controlling blend of vitamin C (250 mg, taken twice daily) and phytosterols (60 mg of beta-sitosterol, taken twice daily), along with a direct immune-boosting dose of echinacea (125 mg, taken twice daily). Unfortunately, she also kept up her steady pre-exam diet of Mountain Dew, M&M's, and inadequate sleep. Despite this less than optimal foundation of diet and sleep for controlling cortisol levels, the supplement regimen appeared to bring Sharon's immune system through midterms with flying colors: She avoided catching a cold during or after her exams that year.