3 ms·

I agree with the other comments, isn't this common sense and known? I have been told this when I was a kid.

• optymizer 8y ago
  I did not know this, but I also didn't grow up in the US.
• vitaflo 8y ago
  Thought the same thing, I thought this was common knowledge. But I live in the upper midwest where low D levels are common in winter, so perhaps it's just discussed here more.
• lm28469 8y ago
  Common sense is wrong as often that it's right, being told something as a kid doesn't help either since you're less likely to question the source.
  • kuon 8y ago
    Yeah of course, there are many things that are widely believed but are false. But we were told this in a 30 minutes course a doctor was giving, in a campaign the schools were doing to educate us about the danger of the sun. A few other things were told, like that there is no total protection sun cream or that even cream that are marked as water resistant do not resist water. That's when we learned that 1mm of "modern glass" would cut nearly all uv light, while it requires nearly 50 meters of water to block it. Of course not all that might be true, but as far as I know, it is pretty accurate.
• izzydata 8y ago
  As I mentioned in another comment I was aware of this fact. I would have been able to tell you as such if someone had asked, but Vitimin D would never have crossed my mind as being an issue.
• dragontamer 8y ago
  The one thing I learned in college was that schools outside of my state are pretty bad with "common sense". "Common sense" is highly localized. My schools had health studies for sure, but no home economics. I had classmates in college who had home economics, but not very robust health classes. Any and all combinations of learning exist in the USA alone. Each State is in charge of its own education department. Travel just 2 or 3 states in any direction, and you'll have a grossly different set of skills being taught at the high-school level.