Excuse me while I go put on a HUGE pot of boiling water................................
Winter is flu season because the sun is at a low angle and people cover up their bodies and do not get sunshine on their skin. Taking vitamin D3 is a substitute for the Sunshine D that is missing in winter. I have not had flu or any cold since I started taking D3 supplements 15 years ago. Same goes for my daughters, son, wife, friends and cousins.