Super Immunity (15 page)

Homeopathy was developed based on theories that are not consistent with accepted modern tenets of chemistry and physics. We also have greater understanding of the so-called placebo effect today and realize how important it is to do double-blind studies when evaluating the efficacy of treatments.

Today the word “homeopathic” is used as a marketing tool to sell herbal and nutritional products that have no resemblance to traditional homeopathic principles. In health food stores, it has turned into a marketing term without real meaning.

A number of bonafide homeopathic remedies are marketed as cold and flu products. Oscillococcinum is among the most popular products marketed for this purpose. A 2006 Cochrane review of this remedy, including three prevention trials and four treatment trials, concluded that it was not effective in preventing infections and had an insignificant effect on the duration of symptoms.
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The role of vitamin C (ascorbic acid) in the prevention and treatment of the common cold has been a subject of controversy for sixty years, but vitamin C is still widely sold and used as both a preventive and a therapeutic agent. A Cochrane systematic review of thirty randomized trials involving more than 11,000 adults concluded that prophylactic vitamin C supplementation (200 milligrams or more daily) is not effective in reducing the incidence of upper-respiratory-tract infections in most adults.

While Vitamin C doesn't reduce the incidence of the common cold in the general population, it may be of some value in a select population with inadequate nutrition or under significant stress. In other words, for those who have inadequate consumption of raw fruits and vegetables (and therefore low levels of vitamin C and other antioxidants and immune-supporting phytochemicals), taking vitamin C may have some protective benefit, especially when those people are under physical or emotional stress; for those who already consume adequate vitamin C through raw fruits and vegetables, taking extra will have no advantage.

Once you are already sick, vitamin C has not been shown to be effective either. In the Cochrane meta-analysis that pooled together numerous studies on this subject, vitamin C demonstrated no benefits compared to placebos when taken at the onset of symptoms.
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Likewise, no benefits were noted in the number of sick days or severity of symptoms.

My take on preventive vitamin C in the undernourished is clear—change to a diet rich in vitamin C and other beneficial nutrients and don't waste your money on supplemental vitamin C. Some nutritional supplements containing vitamins and herbs are marketed as cold fighters. Don't be taken in. Lawsuits for false advertising have ensued because the manufacturers make claims without real data to support their products' efficacy. Keep yourself healthy and disease-resistant all the time, so you don't have to look for magic when you get ill.

Echinacea used in children or adults has been investigated in a significant number of studies and has not been shown to be effective in lessening cold symptoms or shortening the length of illness.
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In some of the studies, this herbal remedy seemed to have a significant benefit in reducing the incidence of viral infections when taken throughout the whole winter, but this result was not consistent among the better-quality, larger studies. This potential benefit may be less valid than reported.
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Certainly, echinacea is not a major cornerstone of improving immunity against infections, though it can be used preventively throughout the winter cold and flu season.

Likewise, other herbs that are often recommended to treat viral infections—such as andrographis, ginseng, astragalus, golden seal, juniper, and pelargonium—may also have mild immune-stimulating effects or mild antihistaminic effects to lessen symptoms. However, the limited data that is available does not support a major shortening of the disease process or offer a major resistance to infection.

Most natural or folk remedies have not been tested in rigorous controlled trials; and for those that have, studies have often had mixed results. Be cautious, and please don't overuse any of the above.

Garlic is a commonly used food and folk remedy for preventing and treating colds. However, there is still insufficient clinical trial evidence regarding the effectiveness of garlic in prevention or treatment. A single trial suggests that garlic may prevent occurrences of the common cold, but more studies are needed to validate this finding. Other studies haven't shown effectiveness of garlic as a treatment for the common cold, and claims of effectiveness appear to rely largely on poor-quality evidence.
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That doesn't mean garlic isn't useful. As we saw earlier, both garlic and onions are immune-enhancing foods. They may not rapidly change your immune function—not quickly enough to make a difference once you've become ill—but eating this family of foods on a regular basis is one of the components of Super Immunity.

My advice: continue to eat onions and garlic throughout the year and throughout any illness.

The phytochemical compound resveratrol, found in the skin of red grapes, in berries, and in peanuts, appears to suppress inflammation and may fight aging in humans; however, long-term clinical trials in humans have not yet documented its benefits.

There
has
been research on this popular plant extract with
non
human subjects. Resveratrol has been shown to prolong life and reduce the rate of aging in worms, fruit flies, and yeast. In rodent studies it has been shown to have anticancer benefits.
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It has also been shown to have antiproliferative effects on human cancer cells, and in a human controlled trial it was shown to decrease inflammatory markers after a high-fat meal.
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Though this and other studies seem promising in terms of the potential anti-aging benefits of this compound in humans, we don't know whether a concentrated extract of resveratrol as a supplement is likely to be as helpful as the data from insect and animal studies suggests. Nevertheless, the data collected so far is promising.

Furthermore, resveratrol seems to have broad antiviral effects. The rodent studies (while not high-quality, controlled human clinical trials) are nevertheless impressive. Studies show that resveratrol inhibits replication of herpes simplex virus (HSV) types 1 and 2 at an early step in the virus replication cycle. Studies in mice also show that resveratrol inhibits or reduces HSV replication in the vagina and inhibits varicella-zoster virus and influenza virus, and enhances the anti-HIV-1 activity of several anti-HIV drugs.

My recommendation here is cautious, but hopeful. Since resveratrol and its related compounds have so many potentially beneficial properties and protect against and fight cancer from so many angles, from angiogenesis inhibition to preventing tumor initiation by deactivating carcinogens,
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I think it likely that supplementing with resveratrol is beneficial; resveratrol may turn out to be an important adjunct, not just preventatively but also for patients who already are diagnosed with cancer. Eating colorful fruits and berries regularly gives us this compound. If you are immune-challenged or susceptible to infections, consider a resveratrol supplement on a regular basis.

Zinc, an essential mineral that plays an important role in immune function, is a nutrient that many people are borderline deficient in. The RDI (recommended daily intake) for zinc is 15 milligrams a day, a quantity not usually achieved by those not taking supplements or eating foods fortified with zinc—especially vegans, vegetarians, or flexitarians not eating seafood and meat daily.

Zinc deficiency leads to dysfunction of both antibody-mediated (humoral) and cell-mediated immunity and thus increases susceptibility to infection. There is considerable evidence to suggest that regular supplementation with zinc or deliberate consumption of foods rich in zinc is useful to improve immune function and fight off both infections and cancer.

Studies have been consistently positive in demonstrating that zinc deficiency is associated with an increased incidence and severity of infections and that zinc supplementation is beneficial.

• Zinc supplementation decreases incidence of pneumonia and antibiotic use.
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• Zinc supplementation decreases the duration of colds and flu by a day or more.

• Maternal zinc supplementation leads to a decrease in infant infections.

• Zinc supplementation decreases child mortality by more than 50 percent.
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The largest and most conclusive analysis of this issue (the respected Cochrane meta-analysis) concluded that once a person had a cold or flu, zinc supplements significantly reduced the severity of cold symptoms as well as the length of illness.
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Among people taking zinc within twenty-four hours of the start of symptoms, the risk of still having symptoms at the seven-day mark was about half that of those not taking zinc. The review found that not only did zinc reduce the duration and severity of common cold symptoms, but regular zinc use also worked to prevent colds, leading to fewer school absences and less antibiotic use in children. In preventing colds, zinc supplements taken for at least five months reduced the risk of catching a cold to only two-thirds that of people not taking the supplements.

Overall, then, it seems prudent to avoid zinc deficiency and regularly supplement with zinc, with the caveat that zinc supplementation, whether throughout the year or only when ill, is not likely to be effective for well-nourished populations with excellent zinc stores already. Those on vegetarian-style diets that are not ideally designed to include sufficient seeds and beans, and those on diets with low calorie intake, should consider taking a zinc supplement on a regular basis (if it is not in the multi you're already taking).

Vitamin D is unique: it is more like a hormone than a vitamin and is not readily found in our food supply. That's why it is often called the sunshine vitamin. It has been suspected for centuries that declining sunlight during winter months could be a factor promoting increases in infections including influenza during the winter. A study done in 2006 with children who were given vitamin D and exposed to the influenza virus documented a reduced incidence of viral respiratory infections in the wintertime.
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This suggests that vitamin D sufficiency may reduce infection to viruses via its ability to modulate the immune system, increasing the effectiveness of major immunity players, including macrophages, neutrophils, monocytes, and natural killer cells. These results have been supported by other studies that show an increased risk for acute lower-respiratory illness in people with low vitamin D levels; additionally, vitamin D deficiency has been associated with an increased risk for influenza.
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Clearly, it is prudent to avoid vitamin D insufficiency. Maintaining adequate levels of vitamin D year-round is an important part of achieving Super Immunity.

Black elderberry juice is widely used to treat colds and the flu. Studies suggest that black elderberry extract (2–3 tablespoons daily for adults and 1–4 teaspoons for children, depending on age) can inhibit the growth of influenza viruses and shorten the duration of influenza symptoms, while enhancing antibody levels against the virus.
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Even though the studies are preliminary, the evidence suggests that these berries have beneficial properties to enhance the body's defense against viral infections, particularly influenza.
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The main flavonoids present in elderberries are the anthocyanins; cyanidin 3-glucoside and cyanidin 3-sambubioside have been identified to increase the defensive function of monocytes against viral-infected cells. More interestingly, elderberry has been demonstrated to inhibit the adhesion of the virus to the cell receptors. When the virus is inhibited from entering cells, it cannot replicate itself, and this can lessen the seriousness of the infection.

Anthocyanins are colored red, purple, black, or blue and are found in berries, eggplant skins, currant and grape skins, cherries, and black rice. Anthocyanins also account for the therapeutic potential of tart cherry juice, which is helpful for inflammatory conditions for the same reason. The small bluish-blackish elderberry is not a sweet-tasting fruit, but when you concentrate it as a liquid syrup or juice, you get a high concentration of these colorful pigments, making absorption more significant than from plain berries. This is one of the few remedies that is safe and very likely has some efficacy without being toxic.