4 ms·

I (Scottish-level white) spend an hour or longer outside every day, all year, in London. Yet my vitamin D levels were almost zero. Unless I take around 50,000 I

I (Scottish-level white) spend an hour or longer outside every day, all year, in London. Yet my vitamin D levels were almost zero. Unless I take around 50,000 IU per week, they drop to insufficient. Not everyone seems to generate enough vitamin D from sun exposure.

bengale 6y ago
Sounds unusual. I thought the paler you were the easier you generated it tbh. Also 50k IU sounds a lot too. I’m pale as fuck an 400iu a day and a quick walk put me in the healthy range.
- lostlogin 6y ago
  > a quick walk put me in the healthy range. Could this be due to where you live? The winter in the UK can be very low light for quite long periods. The weeks-long ‘rain’ or whatever you call that semi drizzle is very dreary. There is about 3x the rainfall per year where I live now but it’s short and sharp in comparison.
  - jessaustin 6y ago
    You're probably right. London is over 51° N latitude. Most people in the hemisphere are well south of that. Most people in Canada live south of that.
    - cameronh90 6y ago
      Europe in general is fairly far north. According to Citymetric, half of Canada's population lives further south than Milan, and the most populated latitude in Europe is 52° N.
      - ghaff 6y ago
        The Gulf Stream distorts a lot of perceptions as does the fact that a lot of the Canadian population lives pretty close to the US border. A lot of people in the US are pretty surprised that London, Amsterdam, and even Paris are at the same latitude as northern Newfoundland and Quebec way north of Montreal.
  - cameronh90 6y ago
    It is essentially overcast from October until March. It barely rains, but it nearly always looks like it's about to rain! That being said, even in the summer, when I regularly go outside enough to get a pinkish hue to my skin, I still don't generate enough Vitamin D. In an ideal world maybe I'd have an explanation for it, but I just take a supplement and don't worry about it any more. Some research suggests that there is a high degree of variability in how much Vitamin D individuals generate from sunlight.
- stjohnswarts 6y ago
  It's pretty standard amount tho. My doctor suggested that, but I opted for a steadier amount when my D levels were low and have been using it ever since. 2 months after he suggested I had been taking 2000IU per day and my levels were back in what he called excellent range. No idea what level that is :) . I am an indoor dweller and in general don't like the sunlight and enjoy night time activities much better.
pge 6y ago
UVB is what causes vitamin D production, and UVB doesn’t penetrate the atmosphere when the sun angle is below about 50deg, so if you are not out when the sun is high enough, it doesn’t help with vitamin D
- cameronh90 6y ago
  It looks like in London, the sun doesn't go above 50deg except between late April and late Aug, and on the solstice it's only above 50deg between 10:30 and 15:30. Which means for the most part, it that condition only occurs while people are inside the office, and only for half of the year.
  - ljosifov 6y ago
    Exactly that. Hence a permanent recommendation by PHE and NICE, that for public health reason, most of UK residents need a supplement. Alas - it is all but forgotten. Mostly acted on for newborns, where the GP surgery, probably reminds the parents or even distribute small bottles of Vitamin D drops. (administered orally) For everyone else, the widespread Vitamin D deficiency, goes virtually unnoticed. It is the default, with no-one pushing for a change. It is a low hanging fruit, wrt Covid-19 and also seasonal flus.

bengale 6y ago

Sounds unusual. I thought the paler you were the easier you generated it tbh. Also 50k IU sounds a lot too. I’m pale as fuck an 400iu a day and a quick walk put me in the healthy range.

lostlogin 6y ago
> a quick walk put me in the healthy range. Could this be due to where you live? The winter in the UK can be very low light for quite long periods. The weeks-long ‘rain’ or whatever you call that semi drizzle is very dreary. There is about 3x the rainfall per year where I live now but it’s short and sharp in comparison.
- jessaustin 6y ago
  You're probably right. London is over 51° N latitude. Most people in the hemisphere are well south of that. Most people in Canada live south of that.
  - cameronh90 6y ago
    Europe in general is fairly far north. According to Citymetric, half of Canada's population lives further south than Milan, and the most populated latitude in Europe is 52° N.
    - ghaff 6y ago
      The Gulf Stream distorts a lot of perceptions as does the fact that a lot of the Canadian population lives pretty close to the US border. A lot of people in the US are pretty surprised that London, Amsterdam, and even Paris are at the same latitude as northern Newfoundland and Quebec way north of Montreal.
- cameronh90 6y ago
  It is essentially overcast from October until March. It barely rains, but it nearly always looks like it's about to rain! That being said, even in the summer, when I regularly go outside enough to get a pinkish hue to my skin, I still don't generate enough Vitamin D. In an ideal world maybe I'd have an explanation for it, but I just take a supplement and don't worry about it any more. Some research suggests that there is a high degree of variability in how much Vitamin D individuals generate from sunlight.
stjohnswarts 6y ago
It's pretty standard amount tho. My doctor suggested that, but I opted for a steadier amount when my D levels were low and have been using it ever since. 2 months after he suggested I had been taking 2000IU per day and my levels were back in what he called excellent range. No idea what level that is :) . I am an indoor dweller and in general don't like the sunlight and enjoy night time activities much better.

pge 6y ago

UVB is what causes vitamin D production, and UVB doesn’t penetrate the atmosphere when the sun angle is below about 50deg, so if you are not out when the sun is high enough, it doesn’t help with vitamin D

cameronh90 6y ago
It looks like in London, the sun doesn't go above 50deg except between late April and late Aug, and on the solstice it's only above 50deg between 10:30 and 15:30. Which means for the most part, it that condition only occurs while people are inside the office, and only for half of the year.
- ljosifov 6y ago
  Exactly that. Hence a permanent recommendation by PHE and NICE, that for public health reason, most of UK residents need a supplement. Alas - it is all but forgotten. Mostly acted on for newborns, where the GP surgery, probably reminds the parents or even distribute small bottles of Vitamin D drops. (administered orally) For everyone else, the widespread Vitamin D deficiency, goes virtually unnoticed. It is the default, with no-one pushing for a change. It is a low hanging fruit, wrt Covid-19 and also seasonal flus.