Sun exposure and Vitamin D

Quicksearch

Blog Administration

RSS Readers

Sunday, July 17. 2016

Sun exposure and Vitamin D

Vit D is essential to health and to healthy growth, especially bone growth. Almost all of human Vit D is produced by skin in response to UV solar radiation. Animals with fur and feathers produce their own.

In its favor, it seems to help prevent some cancers and heart disease, so it is a good guy.

In the US, Vit D is added to commercial milk to make sure kids get some. About 15-20 minutes/day of unprotected sun seems enough to raise Vit D levels but few people get that daily. Sunbathing nude, of course, makes it quicker. Some of it is stored in fat cells for a while, until it gets used up.

Recent evidence suggests that sunblock does not prevent Vit D production in skin very much. In temperate climates, it's not a bad idea to take oral Vit D. I do, and all of my MD friends do. Few people sunbathe in January around here.

When it comes to sun damage and skin cancers, sunburn seems to be the criminal, not some wholesome sun.

Posted by Dr. Joy Bliss in Hot News & Misc. Short Subjects at 17:29 | Comments (8) | Trackbacks (0)

Trackbacks

Trackback specific URI for this entry

No Trackbacks

Comments

Display comments as (Linear | Threaded)

Remember, the wavelength of UVB rays will only penetrate the atmosphere when the sun is above an angle of about 50° from the horizon. When the sun is lower than 50°, the ozone layer reflects the UVB-rays but lets through the longer UVA-rays. The UVB rays must hit the skin to make the chemical reaction that creates Vitamin D. Consult the U.S. Naval Observatory's Sun/Moon Altitude and Azimuth Table for your area to find out when the sun is above 50° on the horizon.
http://aa.usno.navy.mil/data/docs/AltAz.php

#1 Deborah HH on 2016-07-17 18:29 (Reply)

Moonlight is reflected sunlight. Perfect examples below and above. You cannot collect Vit D from satellites

http://www.universetoday.com/wp-content/uploads/2013/12/DSC_0654-1024x687.jpg

#2 tenneseseered on 2016-07-17 20:19 (Reply)

To aid with Vit D and prep for actual sunlight exposure, I use a tanning salon (Horrors!)

Have psoriasis, so regular limited exposure to UV has worked to relieve symptoms and also helps prevent nasty sunburns by establishing a base tan. I keep my exposure to 5 min. per session at low level a few times a month. Haven't suffered a bad burn since doing that.

I also avoid looking like Caspar the Ghost. Might as well get the UV rays to work to your advantage in a controlled exposure environment: I control the time and limit the level. NO need to turn into "sorority girl orange," either.

#3 Earl T on 2016-07-17 20:39 (Reply)

Off topic:

OkCupid: Liberals More Likely to Cry Than Conservatives

QUOTE:

Conservatives are more interested in the outdoors and the gun range while liberals prefer “museums, yoga, and crying,” according to a new study by the online dating website OkCupid.

OkCupid used data from nearly 200,000 profiles for its Words and Politics analysis, which also found that liberals looking for love are vegetarians and conservatives like steak.

“Whether we’re aware of it or not, our political beliefs influence how we advertise ourselves romantically,” the dating site wrote

The analysis also found liberals tend to list “The Daily Show, Broad City, NPR, podcasts, and weed” on their profiles, while conservatives mention “Jesus, faith, guns, and Marines.”

“Steak or avocados? For right-wingers, steak and grilling indicate an interest in sex, while Dr. Pepper points to love,” OkCupid said. “On the left, avocados and vegetarian correlate to love, while booze suggests sex.”

Employed liberals were “likely to be open with feelings,” and those mentioning Quentin Tarantino and Pulp Fiction in their profiles tended to list wanting “pain during sex.”

http://freebeacon.com/culture/okcupid-liberals-likely-cry-conservatives/

#4 feeblemind on 2016-07-17 23:30 (Reply)

"
“Whether we’re aware of it or not, our political beliefs influence how we advertise ourselves romantically,” the dating site wrote
"

It's more likely the other way around... Our political ideology is influenced by our lifestyle/culture, not the other way around (though there is of course cross contamination).

#4.1 J.T.W. on 2016-07-18 01:19 (Reply)

Vitamin D in a bottle doesn't replace sunlight, doctor. Sunlight activates nitric oxide in the skin, and that, not vitamin D specifically, is what accounts for the benefits you mention.

#5 Brian on 2016-07-18 13:05 (Reply)

Being outdoors in the sun just FEELS better. Not to mention it improves mood. At least moderates depression. Vitamin D pills can't be absorbed by everyone anyway. If you can't get outside for at least 15 minutes a day, something is wrong w your life....it staggers me that people have forgotten the ills of tenement life (in our current paranoia about skin cancer) when it was the lack of sunlight and fresh air that led to rickets, fostered TB and other diseases (at least as much as overcrowding and poor diet).

#6 Retriever on 2016-07-18 13:51 (Reply)

Most of us who live in the tropics hate the sun with a passion and try to avoid it whenever possible.

#7 JIm on 2016-07-19 00:33 (Reply)

Add Comment

Name
Email	(Your e-mail will not show in your comment)
Homepage
In reply to
Comment	By commenting on this site you agree to the site rules listed here. Email addresses will not be displayed and will only be used for email notifications. Quick reference guide: [i] italics [/i], [b] bold [/b], [u] underline [/u], [url] (web address) [/url]. More tips here. Enclosing asterisks marks text as bold (word), underscore are made via _word_. E-Mail addresses will not be displayed and will only be used for E-Mail notifications. To prevent automated Bots from commentspamming, please enter the string you see in the image below in the appropriate input box. Your comment will only be submitted if the strings match. Please ensure that your browser supports and accepts cookies, or your comment cannot be verified correctly. Enter the string from the spam-prevention image above: BBCode format allowed
	Remember Information? Subscribe to this entry

Maggie's Farm

Our Recent Essays Behind the Front Page

Categories

Quicksearch

Links

Blog Administration

RSS Readers

Sunday, July 17. 2016

Sun exposure and Vitamin D