None of the B vitamins -- B-12 included -- will help prevent mosquito bites. Vitamin B-12 helps prevent and treat anemia. If you take vitamin B-12 supplements, you might -- in theory, at least -- make your richer blood more attractive to mosquitoes. When it comes to fending off mosquitoes, old-fashioned methods such as using repellents and wearing protective clothing work best, according to the Centers for Disease Control and Prevention.
Vitamin B Myth
The myth about B-12 and its anti-mosquito qualities stems from a few studies dating to the 1960s that said that taking B vitamins produces an odor that mosquitoes dislike, according to "The New York Times." But more recent science dispelled the myth. In a study published in 2005, participants took either vitamin B supplements, vitamin C supplements or no supplements daily for eight weeks. Every two weeks during the trial, A.R. Ives and other researchers from the department of zoology at the University of Wisconsin released swarms of mosquitoes to test the effectiveness of the supplements. Vitamin B supplements, which included vitamin B-12, did not prevent mosquito bites, according to the report published in the June 2005 "Journal of the American Mosquito Association."
Mosquitoes and Disease
Mosquito bites can sometimes prove dangerous. Mosquitoes feed on a variety of animals, including rodents and birds. If the mosquito picks up an infection from an animal, it might carry it to a human victim. Mosquitoes might infect people with diseases such as West Nile virus and encephalitis. These rare complications from mosquito bites sometimes prove fatal. If you experience a fever or headache after being bitten by a mosquito, contact your doctor.
Mosquitoes bite most often at night. Between dawn and dusk, take extra precautions against mosquito bites. Wear long pants, shoes, socks and long-sleeved shirts or jackets. In weather too warm to fully cover up, use insect repellent on exposed body parts. Also spray your clothing with mosquito repellent. Read product labels, since repellents appropriate for your clothing might prove unsafe if used directly on your skin. The CDC recommends using repellents registered with the Environmental Protection Agency, including oil of lemon eucalyptus, DEET and picaridin.
Vitamin B-12 Benefits
Although vitamin B-12 will not prevent mosquito bites, the supplement does treat B-12 deficiency. About one in 30 adults older than 50 suffers from vitamin B-12 deficiency, according to the CDC. Vegans also prove susceptible to B-12 deficiency, since only animal products provide reliable sources of the vitamin. Symptoms of B-12 deficiency include feeling tired or week, loss of vision, changes in personality, memory problems and tingling in your hands and feet. If you believe you might prove deficient in vitamin B-12, talk to your doctor before taking supplements.