Does sunscreen block vitamin D production?

Alan · « **on:** 12/09/2008 16:17:30 »

Alan asked the Naked Scientists:

Hi, I read that you need to spend about 10-20 minutes each day in the sun to allow Vitamin D to form in the body; since I moved to Australia, I have also been told how important it is to wear sunblock.

My question is, does wearing sunblock affect the rate Vitamin D is formed, or is there no difference ?

Thanks, Alan (in Sydney)

What do you think?

Evie · « **Reply #1 on:** 12/09/2008 18:58:04 »

It seems, yes, sunblock will prevent the absorption of UV rays which are what cause your body to produce vitamin D.

Quote

With people spending more time indoors, covering up and slathering on sunblock when they are outside, and smog obscuring the sun on many days, the amount of vitamin D people create naturally is probably very low, many scientists say.

It remains unclear whether vitamin D deficiencies are becoming more common because people are shunning the sun and making other lifestyle changes or whether it is a long-standing problem that is only now being recognized.

http://www.washingtonpost.com/wp-dyn/articles/A43711-2004May20.html

iko · « **Reply #2 on:** 12/09/2008 19:01:37 »

Hi Alan,

we had a similar discussion just a few weeks ago,
and I recommend to watch prof. Michael Holick's
conference (free-video!) to learn all the details
about this crucial issue.
Enjoy

ikod

Quote from: iko on 08/07/2008 20:19:08

Quote from: iko on 29/01/2008 13:29:51
It's never too late (sometimes)...
If you followed this thread so far,
you deserve to watch this free video:

"The Vitamin D Pandemic and its Health Consequences"

Presented by Michael Holick, PhD, MD, Professor of medicine, physiology and biophysics
and director of the General Clinical Research Center at Boston University Medical Center
Keynote address at the opening ceremony of the 34th European Symposium on Calcified Tissues, Copenhagen 5 May, 2007
http://www.uvadvantage.org/portals/0/pres/

Hi Sean More,

find the answer in this interesting overview on vitamin D by Prof. Michael Holick:
certain sunscreens stop 99% ultraviolet B radiation, causing 99% drop in vitamin D production by the skin.
I'll find out the slide and data for you, but it will take some time...

Quote from: iko on 29/01/2008 18:02:39

Try to start from: http://www.vitamindcouncil.com/

First "Item of interest":
Quote
Video of Professor Michael Holick explaining the vitamin D revolution.
Michael Holick, a respected Vitamin D researcher recently gave keynote address about Vitamin D.
It is a great overview of the entire situation. Watch the video- The Vitamin D Pandemic and its Health Consequences

...it should work! []

I'm watching it over and over...to improve my english of course!
(Joke, I love this stuff: even helicobacter connections are mentioned)

ikoD [^]

http://www.uvadvantage.org/portals/0/pres/video/video/slides/slide128.jpg

http://www.uvadvantage.org/portals/0/pres/video/video/slides/slide129.jpg

http://www.uvadvantage.org/portals/0/pres/video/video/slides/slide134.jpg