Re: Data on Vitamin D from Sunlight

[Guest guest]

This says 10 - 15 mins face, arm, hands and neck, twice per week. A long way short of visible effects.

http://ods.od.nih.gov/factsheets/vitamind.asp

Sun exposureSun exposure is perhaps the most important source of vitamin D because exposure to sunlight provides most humans with their vitamin D requirement [13]. UV rays from the sun trigger vitamin D synthesis in skin [13-14]. Season, geographic latitude, time of day, cloud cover, smog, and sunscreen affect UV ray exposure and vitamin D synthesis [14]. For example, sunlight exposure from November through February in Boston is insufficient to produce significant vitamin D synthesis in the skin. Complete cloud cover halves the energy of UV rays, and shade reduces it by 60%. Industrial pollution, which increases shade, also decreases sun exposure and may contribute to the development of rickets in individuals with insufficient dietary intake of vitamin D [15]. Sunscreens with a sun protection factor (SPF) of 8 or greater will block UV rays that produce vitamin D, but it is still important to routinely use sunscreen to help prevent skin cancer and other negative consequences of excessive sun exposure. An initial exposure to sunlight (10 -15 minutes) allows adequate time for Vitamin D synthesis and should be followed by application of a sunscreen with an SPF of at least 15 to protect the skin. Ten to fifteen minutes of sun exposure at least two times per week to the face, arms, hands, or back without sunscreen is usually sufficient to provide adequate vitamin D [14]. It is very important for individuals with limited sun exposure to include good sources of vitamin D in their diet.

14 Holick MF. Vitamin D: the underappreciated D-lightful hormone that is important for skeletal and cellular health. Curr Opin Endocrinol Diabetes 2002;9:87-98.

Regards.

[ ] Data on Vitamin D from Sunlight

Hi folks:The number of minutes it takes for an untanned, full-body, caucasian exposure to summer sun to create the maximum practical daily dose of cutaneous vitamin D is supposed to be a long way short of how long it takes to see any visible effects on the skin (tan or burn, 'suberythematic').I have been looking for, and have not yet tripped over, data for how long this full vitamin D dose exposure time is. And to the extent it varies by latitude, very approximately by how much.If anyone knows where this data can be found I would very much appreciate a reference/link.Thank you.Rodney.

[Guest guest]

This says 10 - 15 mins face, arm, hands and neck, twice per week. A long way short of visible effects.

http://ods.od.nih.gov/factsheets/vitamind.asp

Sun exposureSun exposure is perhaps the most important source of vitamin D because exposure to sunlight provides most humans with their vitamin D requirement [13]. UV rays from the sun trigger vitamin D synthesis in skin [13-14]. Season, geographic latitude, time of day, cloud cover, smog, and sunscreen affect UV ray exposure and vitamin D synthesis [14]. For example, sunlight exposure from November through February in Boston is insufficient to produce significant vitamin D synthesis in the skin. Complete cloud cover halves the energy of UV rays, and shade reduces it by 60%. Industrial pollution, which increases shade, also decreases sun exposure and may contribute to the development of rickets in individuals with insufficient dietary intake of vitamin D [15]. Sunscreens with a sun protection factor (SPF) of 8 or greater will block UV rays that produce vitamin D, but it is still important to routinely use sunscreen to help prevent skin cancer and other negative consequences of excessive sun exposure. An initial exposure to sunlight (10 -15 minutes) allows adequate time for Vitamin D synthesis and should be followed by application of a sunscreen with an SPF of at least 15 to protect the skin. Ten to fifteen minutes of sun exposure at least two times per week to the face, arms, hands, or back without sunscreen is usually sufficient to provide adequate vitamin D [14]. It is very important for individuals with limited sun exposure to include good sources of vitamin D in their diet.

14 Holick MF. Vitamin D: the underappreciated D-lightful hormone that is important for skeletal and cellular health. Curr Opin Endocrinol Diabetes 2002;9:87-98.

Regards.

[ ] Data on Vitamin D from Sunlight

Hi folks:The number of minutes it takes for an untanned, full-body, caucasian exposure to summer sun to create the maximum practical daily dose of cutaneous vitamin D is supposed to be a long way short of how long it takes to see any visible effects on the skin (tan or burn, 'suberythematic').I have been looking for, and have not yet tripped over, data for how long this full vitamin D dose exposure time is. And to the extent it varies by latitude, very approximately by how much.If anyone knows where this data can be found I would very much appreciate a reference/link.Thank you.Rodney.

[Guest guest]

No argument - there may be many factors, but do you feel it's necessary to get a tan to get enough D?

I doubt I'm gonna read another book by anyone on any subject unless it's a medical text.

There has to be a way to resolve this issue and it sounds like a blood test for those concerned about vitamin D levels.

I'm convinced Rodney has a point about D and BP. Course he lives in Canada and I in Texas where the thought of not enough sun is just plain silly. And I don't get enough to tan much, but I could go out right now and spend several hours and not burn.

I'm minimizing my endogenous D, except maybe Cod liver oil which I think is very important for DHA. 0.26 gm per 0.5 tsp.

Wonder if dry milk really has vit D in it?

Regards.

* [ ] Data on Vitamin D from Sunlight> > Hi folks:> > The number of minutes it takes for an untanned, full-body, caucasian> exposure to summer sun to create the maximum practical daily dose of> cutaneous vitamin D is supposed to be a long way short of how long it> takes to see any visible effects on the skin (tan or> burn, 'suberythematic').> > I have been looking for, and have not yet tripped over, data for how> long this full vitamin D dose exposure time is. And to the extent it> varies by latitude, very approximately by how much.> > If anyone knows where this data can be found I would very much> appreciate a reference/link.> > Thank you.> > Rodney.

[Guest guest]

No argument - there may be many factors, but do you feel it's necessary to get a tan to get enough D?

I doubt I'm gonna read another book by anyone on any subject unless it's a medical text.

There has to be a way to resolve this issue and it sounds like a blood test for those concerned about vitamin D levels.

I'm convinced Rodney has a point about D and BP. Course he lives in Canada and I in Texas where the thought of not enough sun is just plain silly. And I don't get enough to tan much, but I could go out right now and spend several hours and not burn.

I'm minimizing my endogenous D, except maybe Cod liver oil which I think is very important for DHA. 0.26 gm per 0.5 tsp.

Wonder if dry milk really has vit D in it?

Regards.

* [ ] Data on Vitamin D from Sunlight> > Hi folks:> > The number of minutes it takes for an untanned, full-body, caucasian> exposure to summer sun to create the maximum practical daily dose of> cutaneous vitamin D is supposed to be a long way short of how long it> takes to see any visible effects on the skin (tan or> burn, 'suberythematic').> > I have been looking for, and have not yet tripped over, data for how> long this full vitamin D dose exposure time is. And to the extent it> varies by latitude, very approximately by how much.> > If anyone knows where this data can be found I would very much> appreciate a reference/link.> > Thank you.> > Rodney.

[Guest guest]

jwwright wrote:

> No argument - there may be many factors, but do you feel it's necessary

> to get a tan to get enough D?

> I doubt I'm gonna read another book by anyone on any subject unless it's

> a medical text.

> There has to be a way to resolve this issue and it sounds like a blood

> test for those concerned about vitamin D levels.

>

> I'm convinced Rodney has a point about D and BP. Course he lives in

> Canada and I in Texas where the thought of not enough sun is just plain

> silly. And I don't get enough to tan much, but I could go out right now

> and spend several hours and not burn.

>

> I'm minimizing my endogenous D, except maybe Cod liver oil which I think

> is very important for DHA. 0.26 gm per 0.5 tsp.

> Wonder if dry milk really has vit D in it?

>

> Regards.

>

>

I have no idea. If anything a deep tan is probably evidence of too much

sun.

If someone lives in the great white north, and rarely goes outdoors,

they may benefit from supplementing Vit D... There's a reason us monkeys

shed our hair and grew progressively more fair skinned as we evolved in

more northern latitudes.

Perhaps one could search for what the overdose symptoms are from too

much Vit D ?

JR

[Guest guest]

jwwright wrote:

> No argument - there may be many factors, but do you feel it's necessary

> to get a tan to get enough D?

> I doubt I'm gonna read another book by anyone on any subject unless it's

> a medical text.

> There has to be a way to resolve this issue and it sounds like a blood

> test for those concerned about vitamin D levels.

>

> I'm convinced Rodney has a point about D and BP. Course he lives in

> Canada and I in Texas where the thought of not enough sun is just plain

> silly. And I don't get enough to tan much, but I could go out right now

> and spend several hours and not burn.

>

> I'm minimizing my endogenous D, except maybe Cod liver oil which I think

> is very important for DHA. 0.26 gm per 0.5 tsp.

> Wonder if dry milk really has vit D in it?

>

> Regards.

>

>

I have no idea. If anything a deep tan is probably evidence of too much

sun.

If someone lives in the great white north, and rarely goes outdoors,

they may benefit from supplementing Vit D... There's a reason us monkeys

shed our hair and grew progressively more fair skinned as we evolved in

more northern latitudes.

Perhaps one could search for what the overdose symptoms are from too

much Vit D ?

JR

[Guest guest]

Hi folks:

From Oregon State, Linus ing Institute:

" Toxicity

Vitamin D toxicity (hypervitaminosis D) induces abnormally high serum

calcium levels (hypercalcemia), which could result in bone loss,

kidney stones, and calcification of organs like the heart and kidneys

if untreated over a long period of time. When the Food and Nutrition

Board of the Institute of Medicine established the tolerable upper

intake level (UL) for vitamin D, published studies that adequately

documented the lowest intake levels of vitamin D that induced

hypercalcemia were very limited. Because the consequences of

hypercalcemia are severe, the Food and Nutrition Board established a

very conservative UL of 2,000 IU/day (50 mcg/day) for children and

adults (see table below) (28). Research published since 1997 suggests

that the UL for adults is likely overly conservative and that vitamin

D toxicity is very unlikely in healthy people at intake levels lower

than 10,000 IU/day (36, 76, 77). Vitamin D toxicity has not been

observed to result from sun exposure. Certain medical conditions can

increase the risk of hypercalcemia in response to vitamin D,

including primary hyperparathyroidism, sarcoidosis, tuberculosis, and

lymphoma (36). People with these conditions may develop hypercalcemia

in response to any increase in vitamin D nutrition and should consult

a qualified health care provider regarding any increase in vitamin D

intake. "

Rodney.

--- In , <crjohnr@...>

wrote:

> Perhaps one could search for what the overdose symptoms are from

too

> much Vit D ?

>

> JR

[Guest guest]

Hi folks:

From Oregon State, Linus ing Institute:

" Toxicity

Vitamin D toxicity (hypervitaminosis D) induces abnormally high serum

calcium levels (hypercalcemia), which could result in bone loss,

kidney stones, and calcification of organs like the heart and kidneys

if untreated over a long period of time. When the Food and Nutrition

Board of the Institute of Medicine established the tolerable upper

intake level (UL) for vitamin D, published studies that adequately

documented the lowest intake levels of vitamin D that induced

hypercalcemia were very limited. Because the consequences of

hypercalcemia are severe, the Food and Nutrition Board established a

very conservative UL of 2,000 IU/day (50 mcg/day) for children and

adults (see table below) (28). Research published since 1997 suggests

that the UL for adults is likely overly conservative and that vitamin

D toxicity is very unlikely in healthy people at intake levels lower

than 10,000 IU/day (36, 76, 77). Vitamin D toxicity has not been

observed to result from sun exposure. Certain medical conditions can

increase the risk of hypercalcemia in response to vitamin D,

including primary hyperparathyroidism, sarcoidosis, tuberculosis, and

lymphoma (36). People with these conditions may develop hypercalcemia

in response to any increase in vitamin D nutrition and should consult

a qualified health care provider regarding any increase in vitamin D

intake. "

Rodney.

--- In , <crjohnr@...>

wrote:

> Perhaps one could search for what the overdose symptoms are from

too

> much Vit D ?

>

> JR