Cranberries & the Flu

Influenza, commonly known as flu, is an infection that affects lungs and airways and is caused by type A and B influenza viruses, according to Merck Manuals. Common symptoms include malaise, fever, sore throat and runny nose, as well as muscle pain and headaches. Cranberry juice or pills may help you fight influenza viruses. Talk to a qualified health care provider before taking any natural supplements, including cranberry products for your condition.

Identification

The cranberry is native to eastern North America, now widely cultivated in the Northeastern and North Central United States. Cranberries are used fresh for juice preparation or dried and used as extracts. Cranberry pills or capsules contain the powdered juice concentrate, explains Steven Foster, co-author of National Geographic's "Desk Reference to Nature's Medicines." For medicinal purposes, Foster suggests using cranberry capsules rather than juices because most commercial cranberry juices contain little fruit and excessive amounts of sweeteners.

Folk Medicine

Native Americans used cranberries in raw form for respiratory conditions, particularly lung infections, according to Foster. In the 1800s cranberry juice became popular for its efficacy in fighting bacterial infections of the stomach and urinary tract infections.

Research

Key ingredients in cranberries are tannins, flavonoids and vitamin C, which are nutrients with antioxidant qualities that help boost the immune system, thus being beneficial for fighting viruses that cause flu.

In animal models, cranberry extract has the ability to inhibit type A and B influenza viruses from attaching to cells, helping to reduce the infections, and they have therapeutic potential, says EI. Weiss, in a study conducted by Hebrew University-Hadassah and Tel Aviv University in Israel, titled Cranberry juice constituents affect influenza virus adhesion and infectivity, which was published in the April 2006 issue of "Antiviral Research."

Professor Itzhak Ofek, researcher at Tel Aviv University's Sackler Faculty of Medicine believes that cranberry has a "teflon-like" efficacy against infectious agents, suggesting that this berry has specific antiviral properties against flu infection, among other benefits. For fighting infections, Ofek recommends two glasses a day of cranberry juice, noting that most of his research indicates that this juice is mostly beneficial for women.The summary of Ofek's research was published in the January 2008 issue of "Medical News Today."

Considerations

If you have an influenza infection, you can freely consume cranberries and other berry fruits on a daily basis. However, if you consider taking cranberry pills, consult a qualified health care practitioner to find out the optimal dosage, possible side effects and interactions with other drugs or herbs. Cranberry supplements do not replace any conventional drugs you may be taking and have not been approved by the U.S. Food and Drug Administration to treat flu or any other medical condition.