Vitamin D and the sun

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Cat-a-Tonic

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I know a lot of us are deficient in vitamin D. I take supplements all winter as there isn't much sun, but I would like to try to get my vitamin D the natural way, through sunlight on my skin, this summer. But I realized that I have a lot of questions and am hoping someone more knowledgeable than I am can answer these!

I know that vitamin D from sunlight is absorbed through the skin. If you apply sunblock, will you still absorb vitamin D? Will you absorb as much as you would if you didn't have sunblock on?

Do you get more vitamin D when the sun is high in the sky? For example, around noon, will I get significantly more vitamin D than at 9 AM or 3 PM even if the sun is shining brightly at those times?

Can I absorb vitamin D from sunlight through a window? A car window? Or do I have to be outside? Can I absorb vitamin D on a partly cloudy day?

This is probably too silly to even ask, but if I get a sun lamp for winter, any chance I could absorb vitamin D from it? I know those things help with stuff like Seasonal Affective Disorder (SAD) but I don't know much else about them.
 
1. Putting on sunblock negates just about every single beneficial aspect of being in the sun and you do not absorb vitamin D. It has been shown that wearing just SPF 8 sunscreen reduces Vitamin D synthesis via sunlight by 95%.

2. High is the sky is best.

3. Negative on the window, go outside :) Cloudy days reduce it but there's lots of variables there so it's hard to say how much. Source for these two answers.

4. I'm not well educated on the sun lamps, I'll defer to someone else on that one :)
 
Thanks David! That's quite helpful! Wow, I usually slather on the sunblock so no wonder I needed vitamin D supplements. I don't want skin cancer but do want vitamin D so I guess I will have to pick and choose which times I want to wear sunblock.

And darn, I was hoping maybe I could sit by the window at work and absorb a little vitamin D. Oh well!
 
According to vitamindcouncil.org vitamin D is shown to help prevent skin cancer. It's the people who go out and get burnt once or twice a year and then stay out of the sun or use sunblock the rest of the time that get themselves in trouble. Get enough sun to get your vitamin D and don't get burnt and from what they say, your risk of skin cancer will drop.
 
I would think sitting by a window would still give Vitamin D. I always thought "if you can get a sun burn, you're getting vitamin D". I've definitely gotten sunburns from driving in a car
 
Apparently we're supposed to get at least a half hour, everyday, without sun screen. And that protects against skin cancer, but like David said, getting burnt is the problem.
Unless your on azathiroprine, in which case you shouldn't even have 5 min a day, of unprotected sunlight. And if you were ever on it, it takes 6 months to fully leave your system. Highest dose was 200mg, though I went down to 150mg, still now 4 months not taking it, I still get that burning feeling after only a short amount of time in the sun :)
 
I would think sitting by a window would still give Vitamin D. I always thought "if you can get a sun burn, you're getting vitamin D". I've definitely gotten sunburns from driving in a car

You can't get a sun burn through a window, nor do you get any VitD. Perhaps your window was down lol. I usually end up with the "car tan" where my left arm is brown and right arm is ghostly white haha.

As far as I know, 30 mins a day sans sunscreen is generally considered efficient.

As for the sun lamps, most do cause some VitD production. It's the UVb that the body uses, which is emitted from sun lamps and tanning beds, although not as much as natural sunlight!
 
I don't know the answer but sun block and sun screen are different. Sun BLOCKS all but screen just blocks harmful rays.
 
The nice part about obtaining vitamin D3 through sun exposure is that there are about a dozen other helpful substances created in the skin other than just vitamin D3. The other items are little understood at this point from what I've read, but clues are being learned. In particular vitamin D3 that is created naturally from UVB rays lasts twice as long in the body as compared to D3 vitamins. Additionally I've read, if my memory is correct, that people with multiple sclerosis benefit from a high vitamin D3 testing level, but that supplements do not seem to hep as much as vitamin D3 made naturally from sun exposure.

Thought to mention that I've read conflicting reports about being able to wipe off the skin vitamin D3 that has been made naturally. Some say it is possible to remove much of the D3 made when exposed to the sun. Others mention that this is not the case.

UVB rays that make vitamin D3 in our skin are present most around noon. As the sun comes up or goes down, more of the suns UVB rays are filtered by the atmosphere. When sunning later in the day, say 3:00, you will be obtaining mainly UVA rays which are the rays associated with tanning, wrinkling, and cancers.

As for a sunlamp, there are different lamps or light boxes out there. The light used for helping with winter blues is different than a UVB lamp.

I personally have and use one of these D3 lamps.

http://tanningbeds.mercola.com/tanning-beds/standup-tanning-systems.aspx

I've also seen Dr. Holick write about using sun D3 lamps helping raise crohn's patients D3 levels. I forget which lamp he recommends.

http://vitamindhealth.org/

And thought this a good article by a cardiologist about his experience working with patients taking vitamin D3 supplements, along with sun tanning.

"Getting vitamin D right"

http://blog.trackyourplaque.com/2010/01/getting-vitamin-d-right.html

Hope that helps. Best of luck! I've personally found some sun exposure gives me an extra kick of energy.
 
You can't get a sun burn through a window, nor do you get any VitD. Perhaps your window was down lol. I usually end up with the "car tan" where my left arm is brown and right arm is ghostly white haha.

As far as I know, 30 mins a day sans sunscreen is generally considered efficient.

As for the sun lamps, most do cause some VitD production. It's the UVb that the body uses, which is emitted from sun lamps and tanning beds, although not as much as natural sunlight!


I was actually going to add that but I thought it would sound stupid. I was going to ask if it would make a difference if the window was open or not because like you said with the window down if it is nice enough I would have the car window down instead of using the AC so that would make sense. And yes, Don't you hate when one side of your body is brown while the other still looks like Casper the ghost haha
 
Hi,

VitD is NOT absorbed from sunlight,
it is produced from 7-dehydrocholesterol by a reaction called photosynthetic
(this means that UVB reacts with 7-dhc to create vitD in your skin and just below it).

VitD is used by your body to process CALCIUM. without vitD the calcium can create serious bone and nerve problems and other medical conditions.

People do not realise that sunlight consists of many different wavelengths of light, just take a look at a RAINBOW and you will see a good few of them, even so there are still others that you cant see like ULTRA VIOLET and INFRA RED.

The UV (ultra violet) can be broken down into types, but generally there are 3 types that are talked about, which are called surprisingly UVA and UVB and UVC - there all very different in what they do and what affects them.



a few things to know -

First of all UVC does not really come into what you need to know as such, reason being the atmosphere filters it out 100%,
otherwise we wouldnt be here,
UVC actually brakes down the bonds in DNA strands and also destroys cell structures, UVC is what the industry uses to kill germs in water and to make medical equipment completely sterile.:voodoo:

UVA is responsible for sunburn ,:p
UVB is required for the body to produce vit D.:ybiggrin:

UVA will go through glass but will be reduced in quantity, therefore you CAN get sunburn in a car, be it over a longer period of time.

thin glass or plastic (perspex, polycarbonate etc)will block UVB 100%,
UVB does not penetrate air very well

UVA and UVB are both dangerous to your eye`s in high levels.

sunbeds are UVA they DO NOT produce any usable amount of UVB
(most sunbeds/lamps have a glass sheet what you lay on or is there to stop you touching the bulbs/tubes, therefore no uvb).


if your really into this then what you need to do is obtain a ARCADIA D3 bulb ( or equivalent ) and use it to replace a normal light bulb in a room where you often sit, you can then get as much UVB, and a little UVA as you want.

Please remember to wear either sunglasses , normal glasses or a peek cap to protect eyes from exposure. also READ THE UVB BULB SPECS - some only produce UVB for very short distances ( inches ) others can reach a bit more ( 5 feet ), remember though almost anything can block out the uvb.

UVB sources have to be replaced every 6 - 12 months as the bulb coating burns out. ( they will still light up but there is no UVB, some of the UVB bulbs ( especially Mercury vapour) also run very hot and will need heat resistant fittings.

low UVB - flourescent strips ( < £20 needs extra fittings to work)
med UVB - dedicated incandescent bulb ( £30 - £50 standard large screw fitting)
high UVB - Mercury vapour bulb ( £50 - £200 standard large screw fitting HEAT PROOF)

for more info and where to get them check out any REPTILE STORE.


as to this link .. http://tanningbeds.mercola.com/tanni...g-systems.aspx there is very little fact, but a whole lot of sales junk and waffle.. wouldnt go there IMHO.
 
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Interesting about the reptile vitamin D bulbs, and the need to change bulbs out often. I've wondered about that, if the reptile UVB lights would be good enough for human use. Figured they probably were but I didn't look into it.
 
Interesting about the reptile vitamin D bulbs, and the need to change bulbs out often. I've wondered about that, if the reptile UVB lights would be good enough for human use. Figured they probably were but I didn't look into it.

the reptile requirements for UVB is much higher than ours,
the bulbs for uvb are exactly the same except special human bulbs probably cost ten times the amount.

the mercury vapour lights are the best by a long way, there the nearest thing to natural sun ( you will notice the difference straight away), mercury vapour is what is used on very powerfull search lights and even on some street lights (with UVA + UVB filtered off).
 
This might be a daft question, but I am medium dark skinned, and do not burn easily. Is it right that as I am on azathioprine I shouldn't go out in the sun at all without sunscreen on? Last summer I only used sunscreen if I was going to be out for an hour or more and it was a really sunny day (usually I do not wear sunscreen in the UK, only if I go on holiday).
 
My daughter gi still what her wants her to have some sun exposure. 10 mins in summer and 2 x 20 mins in winter. We have a uv index on our weather reports, sun exposure should be when the index is 3 or less.

Hope this helps
 
Hey Rebecca,

Yes, you should use sunscreen even without being on Aza as you can still be at risk of skin cancer but definitely use it when taking Azathioprine.

Due to your skin colour and distance from the equator you are also at greater risk of Vitamin D deficiency so it may be worthwhile having your levels tested if you haven't already done so.

Dusty. xxx
 
I recall that Dr. Eades wrote a couple reviews of Dr. Holick's book on vitamin D3. Dr. Holick is one of the top researchers in the US on the topic of the sunshine vitamin. In his book Dr. Holick dedicated a section on how to obtain vitamin D3 safely naturally, and how to supplement when the sun goes missing. Thought the review articles might be of help.

"Sunshine Superman"

http://www.proteinpower.com/drmike/supplements/sunshine-superman/

&

"Heliophobe Madness"

http://www.proteinpower.com/drmike/supplements/heliophobe-madness/
 
Yes, you should use sunscreen even without being on Aza as you can still be at risk of skin cancer but definitely use it when taking Azathioprine.
I understand using sunscreen if you're on Aza but you feel they should use it even if they're not on Aza despite the fact that it will stop virtually all synthesis of vitamin D not to mention the other 5-10 photoproducts derived from adequate sun exposure?
 
I thought you were only at increased risk of skin cancer if you get burnt?

I have had my levels tested and am not deficient, I do take a low dose of D3 as a precautionary measure. But I figure if I wasn't deficient in the middle of winter (when I was tested) I shouldn't have too much trouble.
 
Oh, and last summer I was on aza and went out in the sun without sunscreen with no apparant problems like heat rash, so does that mean I'm OK or could there be invisible problems?
 


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