Naked Science Forum

Life Sciences => Physiology & Medicine => COVID-19 => Topic started by: EvaH on 09/11/2020 14:28:36

Title: How is a unit of vitamin D defined?
Post by: EvaH on 09/11/2020 14:28:36

Philip asks:

Last week one of the interviewees was talking about vitamin D said the government recommendation was 400 units a day and that he takes 4000. My jar of tablets says each one is 12 μg. How many units is that?

Can you help?

Title: Re: How is a unit of vitamin D defined?
Post by: Bored chemist on 09/11/2020 15:51:29

Assuming wiki has got it right
Conversion: 1 µg (of cholecalciferol/ergocalciferol) = 40 IU.
Or 25 ng per unit.

Title: Re: How is a unit of vitamin D defined?
Post by: set fair on 11/11/2020 18:15:39

I would define it as a millionth of the amount of vitamin D that we should make/ingest annually but others think we can get away with less.

Title: Re: How is a unit of vitamin D defined?
Post by: Bored chemist on 11/11/2020 18:38:57

Quote from: set fair on 11/11/2020 18:15:39

I would define it as a millionth of the amount of vitamin D that we should make/ingest annually but others think we can get away with less.

That's a really stupid choice of unit, isn't it? Because it depends on how much sunshine you get (among lots of other things like body mass).