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Garlic for Mosquitoes?
Edited by: Mary Schroeder, M.S., R.D. & Pat Kendall, Ph.D., R.D., Colorado State - Fall 2003
Garlic, a common staple found in countless kitchens and recipes worldwide, long has been considered a special food - not just for the unique flavor it imparts, but also for its medicinal value. Most of its therapeutic value, as well as its flavor and odor, can be attributed to sulfur compounds contained within the garlic clove. In recent years, garlic has been widely studied for its role in promoting health. There is good evidence that garlic possesses antibacterial, antiviral, antifungal, antiprotozoan and even insect-repellent properties.
Given the recent surge of the West Nile virus spread by infected mosquitoes, it is interesting to explore the value of garlic as one more method for avoiding mosquito bites. A number of studies have shown that the oil fraction of garlic destroys certain species of mosquito larvae. Garlic sprays (made primarily with garlic extract) are available on the market for use on plants as an alternative botanical pesticide to chemical pesticides. The sulfurs contained within the garlic extract have been shown to be effective against a wide range of insects, including mosquitoes, and the lingering odor can deter mosquitoes from the area for weeks.
It is thought that garlic may be an alternative mosquito repellent for humans as well. In a field study conducted in India, a preparation made of 1 percent garlic oil, petroleum jelly and beeswax that was rubbed on the arms and legs of study subjects was found to be effective in preventing mosquito bites for up to eight hours.
In addition, there is some evidence that heavy consumption of garlic through supplements or well-flavored foods may help ward off mosquitoes. When garlic is eaten and its components are metabolized, compounds are released from the body through the skin and the breath. Although they may not be detectable by others (or may, in the case of garlic breath!), mosquitoes use smell to locate a host. For example, carbon dioxide and lactic acid released from the breath of humans are two known mosquito attractants that can be detected within 40 yards. While it has not been proven through clinical studies, it is thought that the sulfur compounds present on the skin and in the breath after eating garlic may help ward off those pesky mosquitoes.
Before deciding to use garlic supplements, it's best to consult with your health care provider. For example, garlic supplements are not recommended for pregnant or lactating women, for persons on blood thinning medications, for those going into surgery or for those on certain medications such as the anti-HIV drug Saquinavir.
The bottom line: Mosquito repellents containing DEET are still your best bet for avoiding mosquitoes - but a little garlic breath may also be a good thing.Source:
- Amonkar, S.V., Reeves, E.L. Mosquito Control with Active Principle of Garlic, Allium sativum. Journal of Economic Entomology. 63(4): 1172-1175, 1970
- Bhuyan, M. Saxena, B.N., Rao, K.M. Repellent Property of Oil Fraction of Garlic, Allium sativum Linn. Indian Journal of Experimental Biology. 12: 575-576, 1974
- Fradin, M.S. Mosquitoes and Mosquito Repellents: A Clinician's Guide. Annals of Internal Medicine, 128: 931-940, 1998
- HDRA- The Organic Organisation. Natural Pesticides No. TNP3: Garlic, Allium sativum. Last updated June, 2000.
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