Vitamin D reduces flu risk
A meta-analysis of 10 randomized controlled trials reports that supplementation with vitamin D reduces the risk of flu by 22%.
Vitamin D supplementation and influenza infection among older adults
The effect of heat-killed Levilactobacillus brevis and beta-carotene on influenza
A bout of resistance exercise does not enhance the response to the influenza vaccine in older adults
Are women more susceptible to the flu than men?
It might be best to skip the gym before getting the flu shot