According to a study at the Jikei University School of Medicine in Japan, a daily supplement of vitamin D3 reduces the overall rate of the common seasonal flu by over 40 percent. The vitamin is crucial for activating T cells, which help the immune system fight off attacks on the body such as the flu.
The study was conducted on two groups of children; one received the vitamin supplement (1,200 IU) while the others received a placebo. After four months, the group who received the daily vitamin D3 had an 8 percent lower rate of influenza.
From here, Canada’s Public Health Agency of Canada (PHAC) is looking into the impact of vitamin D on the H1N1 flu virus.