Remedies for Immunity
The flavonoids are found in the rind of fruits and vegetables. More than four thousand flavonoids have been identified in plants. Flavonoids are beneficial nutrients for health and should be part of any
diet for optimal immunity.
Numerous studies have shown that people eating high- flavonoid diets have a lower-than-average risk of developing heart disease and cancer. These nutrients also enhance the activity of white blood cells and boost the body's defenses against a broad range of infections, from urinary tract infections to HIV.
Cranberry juice has long been a folk remedy for treating urinary tract infections, which are typically caused by a strain of E. coli. The principal antibacterial flavonoid in cranberries (and blueberries), methyl alpha-D-mannopyranoside, works by making the urinary tract slippery for bacteria, which prevents them from adhering and establishing an infection. (1)
In a clinical study of 53 elderly women, half were given a large glass of cranberry juice and the other half a look-alike noncranberry drink with vitamin C. They were asked to drink 1 glass every day for six months. After only two months, the women drinking cranberry juice had half the incidence of urinary tract infections. (2)
Green tea contains a group of diverse
flavonoids, including tannins, gallic acid esters, and catechins. Many of these compounds
stimulate the immune system. Some of the flavonoids promote the body's production and activity of white blood cells, T cells, and antibodies. (3)
Several other flavonoids also possess antibacterial and antiviral properties.
Grape seed extract, a type of flavonoid supplement, contains a number of proanthocyanidins, which have anti-herpes virus properties. (More than 250 proanthocyanidins have been identified in plants.) Grape seed extracts also contain gallic acid esters
as in green tea.
Take a diet containing many different kinds of fruits and vegetables in order to have the most diverse source of flavonoids to build immunity and prevent disease. Take flavonoid supplements when actually fighting an infection.
1. Sobota, A. E., "Inhibition of Bacterial Adherence by Cranberry Juice: Potential Use for the Treatment of Urinary Tract Infections," Journal of Urology, May 1984;131:1013-1016.
2. Avorn, J., et al., "Reduction of Bacteriuria and Pyuria after Ingestion of Cranberry Juice," Journal of the American Medical Association, March 9, 1994;271:751-754.
3. Berg, P. A., and Daniel, P. T., "Effects of Flavonoid Compounds on the Immune Response," in Plant Flavonoids in Biology and Medicine II: Biochemical, Cellular, and Medicinal Properties, Cody, V., et al., eds., Alan R. Liss Inc., New York, 1988, 157-171.
4. Nakayama, M., et al., "Inhibition of the Infectivity of Influenza Virus by Tea Polyphenols," Antiviral Research, August 1993;21:289-299.
5. Mukoyama, A., et al., "Inhibition of Rotavirus and Enterovirus Infections by Tea Extracts," Japanese Journal of Medical Science and Biology, August 1991;44:181-186.
6. Horiuchi, Y., et al., "Protective Activity of Tea and Catechins against Bordetella pertussis," Kansenshogaku Zasshi -Journal of the Japanese Association for Infectious Diseases, May 1992;66:599-605.
7. Chosa, H., et al., "Antimicrobial and Microbicidal Activities of Tea and Catechins against Mycoplasma," Kansenshogaku Zasshi-Journa[ of the Japanese Association for Infectious Diseases, May 1992;66:606-611.
8. Toda, M., et al., "Antibacterial and Bactericidal Activities of Tea Extracts and Catechins against Methicillin-Resistant Staphylococcusaureus," Nippon Saikingaku Zasshi -Japanese Journal of Bacteriology, September 1991; 46:839-845.
9. Kono, K., et al" "Antibacterial Activity of Epigallocatechin Gallate against Methicillin-Resistant Staphylococcus aureus," Kansenshogaku Zasshi- Journal of the Japanese Association for Infectious Diseases, December 1994; 68:1518-1522.