Hacker News Reader

Unless you spend literally hours outside every day, it's not likely to be enough.

Get some cod liver oil, drink a tablespoon every day. Does wonders.

I heard British prof Steve Jones on the radio recently say that 15 minutes in the middle of the day was enough at this time of year.

Posts like this really need to specify what type of person they are talking about. 15 minutes is very clearly not enough for someone with dark skin.