Vit D supplements

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Vit D supplements

Postby Quiver0f10 » Wed Jun 11, 2008 8:31 am

I had my blood work done recently and the only thing I was deficient in was Vit D. I was deficient a year ago too and since have been taking a multi with 800 IU vit D and a calcium pill with 400 IU. My Dr gave me a supplenet with 5000 IU of Vit D and I am wondering if combined will that be too high a dose? I realy wanted to keep taking the calcium and multi so I am not sure what to do.

Thanks.
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Re: Vit D supplements

Postby JeffN » Wed Jun 11, 2008 8:49 am

Quiver0f10 wrote:I had my blood work done recently and the only thing I was deficient in was Vit D. I was deficient a year ago too and since have been taking a multi with 800 IU vit D and a calcium pill with 400 IU. My Dr gave me a supplenet with 5000 IU of Vit D and I am wondering if combined will that be too high a dose? I realy wanted to keep taking the calcium and multi so I am not sure what to do.

Thanks.


If you have to take a Vit D supplment, the body can handle large amounts for short periods without toxicity. Some of the upper levels have been questioned as to their validity as people have been given doses of 50,000 without toxicity. The dose you are being recommended would not be toxic for the short term. How long are you supposed to be taking it?

If you want to read a brand new article from the worlds leading authority of Vit D, you can do so here. You may even want to share it with your MD.

ALTERNATIVE THERAPIES, May/jun 2008, VOL. 14, NO. 3, 64-75.
Conversations: Michael Holick, PhD, MD.
MICHAEL HOLICK, PHD, MD: VITAMIN D PIONEER.
Interview by Frank Lampe and Suzanne Snyder. Photography by David Keough.

http://www.alternative-therapies.com/at ... erview.pdf


In regard to building Vit D stores...

ATHM: How long does it take for supplementation to increase
blood levels of vitamin D to an acceptable level?

Dr Holick: When we give 50 000 IU once a week for 8 weeks, it
usually gets the blood level of 25-hydroxyvitamin D to the desired
level of greater than 30 ng/mL. People think that’s too much vita-
min D to take and it will cause vitamin D toxicity, but it’s not. I
joke with my colleagues when I give my presentation that what is
remarkable to me is what physicians seem to remember more
from their medical school days than anything else is, “Don’t ever
make your patient vitamin D intoxicated.” They’ve never seen
vitamin D intoxication. They don’t know what vitamin D intoxica-
tion is, but they know that 50 000 IU is going to cause vitamin D
intoxication. Fifty thousand IU taken once a week for 8 weeks
then once every other week is safe. When you go outside in the
sun one time in a bathing suit, your body makes about 20 000 IUs
when you receive one minimal erythemal dose (light pinkness to
the skin 24 hours after the exposure).

and

Most experts—myself included—agree that vitamin D defi -
ciency is defined as 25-hydroxyvitamin D <20 ng/mL and that
vitamin D insufficiency is between 21 and 29 ng/mL. To obtain
the full benefits of vitamin D for health, many experts recom-
mend that their blood level should be >30 ng/mL. Vitamin D
intoxication is typically not seen until blood levels are above 150
to 200 ng/mL. For every 100 IU of vitamin D ingested, it increas-
es the blood level of 25-hydroxyvitamin D by 1 ng/mL. This is
why both children and adults need to be on at least 1000 IU of
vitamin D a day when they are having inadequate sun exposure
to satisfy their body’s vitamin D requirement.
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Postby Melinda » Wed Jun 11, 2008 10:21 am

Jeff, I got the impression from "The China Study" that taking vitamin D interfered with other chemical processes in the body. We are outside lots in the spring summer and fall, but we live in BC Canada. So should we take Vit. D suppplements?
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Postby JeffN » Wed Jun 11, 2008 10:28 am

Melinda wrote:Jeff, I got the impression from "The China Study" that taking vitamin D interfered with other chemical processes in the body. We are outside lots in the spring summer and fall, but we live in BC Canada. So should we take Vit. D suppplements?


Hi Melinda,

Any isolated concentrated nutrient can interact with other processes in the body, as do any drugs anyone may take. Even many foods interact with other foods and nutrients. But sometimes, in certain situations, the benefit may outweigh the risk.

If you are concerned with your Vit D levels, the best way to know, is to get them tested. If you are low, you then have the option to spend some time in the sun and/or take a supplement and then get retested. In general, I would recommend the sun but not everyone can do that.

According to Dr. Michael Holick (one of our nations leading Vit D experts), as little as 5-10 minutes of sun exposure on arms and legs or face and arms three times weekly between 11:00 am and 2:00 pm during the spring, summer, and fall at 42 degrees latitude should provide a light-skinned individual with adequate vitamin D and allow for storage of any excess for use during the winter with minimal risk of skin damage.

I would recommend you read the discussion here...

http://www.drmcdougall.com/forums/viewtopic.php?t=5604

And the Article I linked above.

In Health
Jeff
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Postby Quiver0f10 » Wed Jun 11, 2008 10:34 am

Thanks for the link. Intersting stuff. The Dr didn't say how long I had to be o nthe supplement, but she did say I should be rechecked down the road. I am going to call and find out. I almost never go outside in the sun and am going to make a point to get some daily sunlight. I hope to get a garden going and that will help with Vit D and good fresh food! :-)
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Postby JeffN » Wed Jun 11, 2008 10:43 am

Quiver0f10 wrote:Thanks for the link. Intersting stuff. The Dr didn't say how long I had to be o nthe supplement, but she did say I should be rechecked down the road. I am going to call and find out. I almost never go outside in the sun and am going to make a point to get some daily sunlight. I hope to get a garden going and that will help with Vit D and good fresh food! :-)


Great Idea!

When you call you may want to fax the linked PDF article above and highlight the part about how to raise Vit D levels back to normal which is...

"Fifty thousand IU taken once a week for 8 weeks then once every other week is safe. "

Then you can get rechecked and hopefully be able to get enough sun (And fresh food) and not need the supplement.

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Postby JeffN » Wed Jun 11, 2008 12:12 pm

Remember, ever study that has been done that has found a percentage of people with low levels has also found a percentage of people with adequate levels even in those who live in the Northern latitudes and not everyone takes Vit D supplements. The concern is that there are more with low levels than they thought and enough for them to be concerned. It was not 100%.

Many people around the world meet their vitamin D needs through exposure to sunlight

Effectiveness and safety of vitamin D. Evidence Report/Technology Assessment No. 158 prepared by the University of Ottawa Evidence-based Practice Center under Contract No. 290-02.0021. AHRQ Publication No. 07-E013. Rockville, MD: Agency for Healthcare Research and Quality, 2007.

http://www.ncbi.nlm.nih.gov/pubmed/1808 ... t=Abstract

Any supplement, even Vit D, has potential for side effects, and adverse effects. Vitamin D toxicity can cause symptoms such as nausea, vomiting, poor appetite, constipation, weakness, and weight loss. More seriously, it can also raise blood levels of calcium, causing mental status changes such as confusion and heart rhythm abnormalities. The use of supplements of both calcium (1,000 mg/day) and vitamin D (400 IU/day) by postmenopausal women was associated with a 17% increase in the risk of kidney stones over 7 years in the Women's Health Initiative. Deposition of calcium and phosphate in the kidneys and other soft tissues can also be caused by excessive vitamin D levels. A serum 25(OH)D concentration consistently >200 ng/mL (>500 nmol/L) is considered to be potentially toxic.

I am also going to refer you to this article by Dr Mcdougall

http://www.drmcdougall.com/misc/2007nl/sep/vd.htm

Gotta run and get some sun before we have our afternoon shower. :)

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Postby JeffN » Wed Jun 11, 2008 2:14 pm

Carroll wrote:but I wonder why people here mention having problems even when attempting to get that sun in?


Here is something to think about....

As we see with supplementation, it takes a very high dose over 2 months to rebuild Vit D stores to a normal level where the deficiency is gone compared to what it would take to just maintain normal levels.

According to Dr Volick, it takes 50,000 Units once a week for 8 weeks than once every other week for 8 weeks. This is the same as about 7000 Units a day for 8 weeks and then 3500 units per day for 8 more weeks. This is much higher than the 1000-2000 units per day needed to maintain healthy levels. So, the amount needed to restore levels may be 3.5 to 7x the level (for 8 weeks) that is needed to maintain the levels.

Therefore, it may take more time in the sun to restore Vit D stores than just to maintain them.

Again, a simple and inexpensive solution is to get your Vitamin D levels checked.

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Postby JeffN » Fri Jun 13, 2008 5:55 am

One thing that is being left out of the equation is the relationship between % Body Fat and Vit D Status, as it turns out there is increasing Vit D deficiency amongst those with higher body fat %. Considering 66% of Americans are overweight and 33% are obese, I wonder how this is effecting some of the results we are seeing in those with "low' Vit D Levels. It would be interesting to see (and I don't know if this has been published yet) but to see what happens to someones Vit D levels if we control for everything except weight and see how it changes as they lose weight.


1) J Clin Endocrinol Metab. 2007 Aug;92(8):3155-7. Epub 2007 May 29. Reduced sun exposure does not explain the inverse association of 25-hydroxyvitamin D with percent body fat in older adults.

CONTEXT: Greater adiposity is associated with lower blood levels of 25-hydroxyvitamin D [25(OH)D]. The extent to which this results from reduced sun exposure among heavier individuals is unknown. OBJECTIVES: This analysis was conducted to determine whether sun exposure habits differ according to percent body fat (%FAT) in older adults and to what extent they explain the inverse association of adiposity with 25(OH)D in that population. DESIGN: We performed a cross-sectional analysis of baseline data from a randomized trial of calcium and vitamin D supplementation to prevent bone loss. SETTING: The study was performed at the Metabolic Research Unit at the Jean Mayer United States Department of Agriculture Human Nutrition Research Center on Aging at Tufts University. PARTICIPANTS: A total of 381 generally healthy male and female volunteers age 65 and older participated in the study. Exclusion criteria included vitamin D and calcium supplement use, and medical conditions and medications known to affect bone metabolism. INTERVENTION: There were no interventions. Measurements for this analysis were made before participants received trial supplements. MAIN OUTCOME MEASURES: Plasma 25(OH)D, an indicator of vitamin D status, was measured. RESULTS: Sunscreen use, hours spent outside per week, and percent of skin exposed did not differ across quartiles of %FAT (P > 0.43). 25(OH)D decreased across %FAT quartiles (P < 0.05) and was about 20% lower in the highest compared with the lowest quartile of %FAT after adjustments for age, sex, season, and vitamin D intake. Further adjustment for sun exposure habits had little effect on estimates of 25(OH)D. CONCLUSIONS: In older adults, sun exposure habits do not vary according to adiposity and do not appear to explain lower 25(OH)D concentrations with increasing adiposity.
PMID: 17535990



2) J Clin Endocrinol Metab. 2005 Jul;90(7):4119-23. Epub 2005 Apr 26 Adiposity in relation to vitamin D status and parathyroid hormone levels: a population-based study in older men and women.P.

OBJECTIVE: In small case-control studies, obesity was associated with worse vitamin D status. Our aim was to assess the association of adiposity (anthropometric measures as well as dual energy x-ray absorptiometry) with serum 25-hydroxyvitamin D (25-OH-D) and serum PTH levels in a large population-based study including older men and women. METHODS: Subjects were participants of the Longitudinal Aging Study Amsterdam and were aged 65 yr and older. In 453 participants, serum 25-OH-D and PTH were determined, and body mass index, waist circumference, waist to hip ratio, sum of skin folds, and total body fat percentage by dual energy x-ray absorptiometry were measured. RESULTS: After adjustment for potential confounders, higher body mass index, waist circumference, and sum of skin folds were statistically significantly associated with lower 25-OH-D (standardized beta values were -0.136, -0.137, and -0.140, respectively; all P < 0.05) and with higher PTH (0.166, 0.113, and 0.114, respectively; all P < 0.05). Total body fat percentage was more strongly associated with 25-OH-D and PTH (-0.261 and 0.287, respectively; both P < 0.001) compared with anthropometric measures. Total body fat percentage remained associated with 25-OH-D after adjustment for PTH, and with PTH after adjustment for 25-OH-D. CONCLUSION: Precisely measured total body fat is inversely associated with 25-OH-D levels and is positively associated with PTH levels. The associations were weaker if anthropometric measures were used, indicating a specific role of adipose tissue. Regardless of the possible underlying mechanisms, it may be relevant to take adiposity into account when assessing vitamin D requirements.
PMID: 15855256


3) Am J Clin Nutr. 2000 Sep;72(3):690-3.
Decreased bioavailability of vitamin D in obesity.

BACKGROUND: Obesity is associated with vitamin D insufficiency and secondary hyperparathyroidism. OBJECTIVE: This study assessed whether obesity alters the cutaneous production of vitamin D(3) (cholecalciferol) or the intestinal absorption of vitamin D(2) (ergocalciferol). DESIGN: Healthy, white, obese [body mass index (BMI; in kg/m(2)) > or = 30] and matched lean control subjects (BMI </= 25) received either whole-body ultraviolet radiation or a pharmacologic dose of vitamin D(2) orally. RESULTS: Obese subjects had significantly lower basal 25-hydroxyvitamin D concentrations and higher parathyroid hormone concentrations than did age-matched control subjects. Evaluation of blood vitamin D(3) concentrations 24 h after whole-body irradiation showed that the incremental increase in vitamin D(3) was 57% lower in obese than in nonobese subjects. The content of the vitamin D(3) precursor 7-dehydrocholesterol in the skin of obese and nonobese subjects did not differ significantly between groups nor did its conversion to previtamin D(3) after irradiation in vitro. The obese and nonobese subjects received an oral dose of 50000 IU (1.25 mg) vitamin D(2). BMI was inversely correlated with serum vitamin D(3) concentrations after irradiation (r = -0.55, P: = 0.003) and with peak serum vitamin D(2) concentrations after vitamin D(2) intake (r = -0.56, P: = 0.007). CONCLUSIONS: Obesity-associated vitamin D insufficiency is likely due to the decreased bioavailability of vitamin D(3) from cutaneous and dietary sources because of its deposition in body fat compartments.
PMID: 10966885



4) J Clin Endocrinol Metab. 2003 Jan;88(1):157-61. Body fat content and 25-hydroxyvitamin D levels in healthy women.

Obesity is associated with alterations in the vitamin D endocrine system. Lower levels of serum 25-hydroxyvitamin D (25-OHD) in morbidly obese individuals may be secondary to an alteration in tissue distribution resulting from an increase in adipose mass. Therefore, morbidly obese individuals are expected to need higher doses of vitamin D supplementation than the general population. However, it is still unknown whether adiposity (or percentage body fat) should be taken into consideration while assessing vitamin D requirements in the general population. To study the relationship between 25-OHD levels and percentage body fat content in healthy women, we studied 410 healthy women between 20 and 80 yr of age with body mass index ranging from 17 to 30 kg/m2. We analyzed the correlation between serum 25-OHD level and percentage body fat measured by dual energy x-ray absorptiometry. We also analyzed the influence of season, dietary vitamin D intake, age, and race on this relationship. The levels of serum 25-OHD inversely correlated with percentage body fat. The correlation was -0.13 (P = 0.013) after adjusting for race, age, season, and dietary vitamin D intake. In a multiple stepwise regression, race and season were found to have a major influence on serum 25-OHD (cumulative R2 = 0.34), and percentage body fat, although modest (additional R2 = 0.02), also had an independent statistically significant influence on serum 25-OHD levels. We conclude, percentage body fat content is inversely related to the serum 25-OHD levels in healthy women.
PMID: 12519845


5) J Clin Invest. 1985 Jul;76(1):370-3. Evidence for alteration of the vitamin D-endocrine system in obese subjects.

Serum immunoreactive parathyroid hormone (PTH) is increased in obese as compared with nonobese subjects and declines with weight loss. To determine whether alteration of the vitamin D-endocrine system occurs in obesity and whether ensuing secondary hyperparathyroidism is associated with a reduction in urinary calcium, a study was performed in 12 obese white individuals, five men and seven women, and 14 nonobese white subjects, eight men and six women, ranging in age from 20 to 35 yr. Body weight averaged 106 +/- 6 kg in the obese and 68 +/- 2 kg in the nonobese subjects (P less than 0.01). Each of them were hospitalized on a metabolic ward and were given a constant daily diet containing 400 mg of calcium and 900 mg of phosphorus. Whereas mean serum calcium, serum ionized calcium, and serum phosphorus were the same in the two groups, mean serum immunoreactive PTH (518 +/- 48 vs. 243 +/- 33 pg/ml, P less than 0.001), mean serum 1,25-dihydroxyvitamin D [1,25(OH)2D] (37 +/- 2 vs. 29 +/- 2, P less than 0.01), and mean serum Gla protein (33 +/- 2 vs. 24 +/- 2 ng/ml, P less than 0.02) were significantly higher, and mean serum 25-hydroxyvitamin D (25-OHD) (8 +/- 1 vs. 20 +/- 2 ng/ml, P less than 0.001) was significantly lower in the obese than in the nonobese men and women. Mean urinary phosphorus was the same in the two groups, whereas mean urinary calcium (115 +/- 10 vs. 166 +/- 13 mg/d, P less than 0.01) was significantly lower, and mean urinary cyclic AMP (3.18 +/- 0.43 vs. 1.84 +/- 0.25 nM/dl GF, P less than 0.01) and creatinine clearance (216 +/- 13 vs. 173 +/- 6 liter/d, P less than 0.01) were significantly higher in the obese than in the nonobese individuals. There was a significant positive correlation between percentage of ideal body weight and urinary cyclic AMP (r = 0.524, P less than 0.01) and between percentage of ideal body weight and serum immunoreactive PTH (r = 0.717, P less than 0.01) in the two groups. The results provide evidence that alteration of the vitamin D-endocrine system in obese subjects is characterized by secondary hyperparathyroidism which is associated with enhanced renal tubular reabsorption of calcium and increased circulating 1,25(OH)2D. The reduction of serum 25-OHD in them is attributed to feedback inhibition of hepatic synthesis of the precursor by the increased serum 1,25(OH)2D.
PMID: 2991340

There are many more like this but as we can see, this is a fairly well established issue.

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Postby JeffN » Fri Jun 13, 2008 6:05 am

JeffN wrote:It would be interesting to see (and I don't know if this has been published yet) but to see what happens to someones Vit D levels if we control for everything except weight and see how it changes as they lose weight.


Looks like they have done it and Vit D levels increased.

Maybe we need to spend more time in the sun being active and losing weight.

Could be a great marketing campaign...

"A Run In The Sun: Winning The Race Against Vit D Deficiency"


In Health
Jeff

Eur J Endocrinol. 2007 Aug;157(2):225-32. Vitamin D status and parathyroid hormone in obese children before and after weight loss.

OBJECTIVE: The roles of vitamin D and parathyroid hormone (PTH) are discussed controversially in obesity, and studies of these hormones in obese children are limited. Therefore, we studied the relationships between PTH, 1,25-dihydroxy-vitamin D (1,25-OH Vit D), 25-hydroxy-vitamin D (25-OH Vit D), weight status, and insulin sensitivity before and after weight loss in obese children. METHODS: Fasting serum PTH, 1,25-OH Vit D, 25-OH Vit D, inorganic phosphate, calcium, alkaline phosphatase (AP), insulin, glucose, and weight status (SDS-BMI and percentage body fat) were determined in 133 obese children (median age 12.1 years) and compared with 23 non-obese children. Furthermore, these parameters were analyzed in 67 obese children before and after participating in a 1-year obesity intervention program. RESULTS: Obese children had significantly (P < 0.001) higher PTH and lower 25-OH Vit D concentrations compared with non-obese children, while calcium, phosphate, AP, and 1,25-OH Vit D did not differ significantly. Changes of PTH (r = 0.23, P = 0.031) and 25-OH Vit D (r = -0.27, P = 0.013) correlated significantly with changes of SDS-BMI, but not with changes of insulin sensitivity (homeostasis model assessment; HOMA-B%). Reduction of overweight in 35 children led to a significant (P < 0.01) decrease of PTH concentrations and an increase in 25-OH Vit D levels. CONCLUSIONS: PTH levels were positively and 25-OH Vit D concentrations were negatively related to weight status. Since these alterations normalized after weight loss, these changes are consequences rather than causes of overweight. A relationship between PTH, vitamin D, and insulin sensitivity based on the HOMA index was not found in obese children. Further longitudinal clamp studies are necessary to study the relationship between vitamin D and insulin sensitivity.
PMID: 17656603
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Postby Quiver0f10 » Wed Jul 02, 2008 4:34 am

My Dr just gave me an Rx for 50000 IU to be taken one a week for 8 weeks. The pharmacist said I can't take my other vitamins along with the Vit D so I am wondering what to do. I have macular degeneration and realy need to take my eye vits.

The pharmacist also said Vit D is fat soluble so Ineed to eat fat with it? Not sure what that means lol.
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Postby JeffN » Wed Jul 02, 2008 5:34 am

Quiver0f10 wrote:My Dr just gave me an Rx for 50000 IU to be taken one a week for 8 weeks. The pharmacist said I can't take my other vitamins along with the Vit D so I am wondering what to do. I have macular degeneration and realy need to take my eye vits.

The pharmacist also said Vit D is fat soluble so Ineed to eat fat with it? Not sure what that means lol.


Vit D can be taken with other supplements and/or medications. I have listen the known interactions below.

Vit D is fat soluble which means it dissolves in fat and is stored in your fat cells. If you are consuming whole foods and following this program you are consuming more than enough fat.

In Health
Jeff


From The Office Of Dietary Supplements

Interactions with Medications
Vitamin D supplements have the potential to interact with several types of medications. A few examples are provided below. Individuals taking these medications on a regular basis should discuss vitamin D intakes with their healthcare providers.

Steroids
Corticosteroid medications such as prednisone, often prescribed to reduce inflammation, can reduce calcium absorption [77-79] and impair vitamin D metabolism. These effects can further contribute to the loss of bone and the development of osteoporosis associated with their long-term use [78-79].

Other medications
Both the weight-loss drug orlistat (brand names Xenical® and alli™) and the cholesterol-lowering drug cholestyramine (brand names Questran®, LoCholest®, and Prevalite®) can reduce the absorption of vitamin D and other fat-soluble vitamins [80-81]. Both phenobarbital and phenytoin (brand name Dilantin®), used to prevent and control epileptic seizures, increase the hepatic metabolism of vitamin D to inactive compounds and reduce calcium absorption [82].
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Postby Quiver0f10 » Wed Jul 02, 2008 12:40 pm

Thanks, Jeff. I am trying natural before I revert to the Rx she gave me. I was able to spend 15 minutes out inthe noon sun today so I hope this works. If not I will start the pills.
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Re: Vit. D Supplements

Postby JeffN » Thu Jul 03, 2008 2:36 pm

Eileen wrote:Can you recommend a brand name. So many choices. I don't know which companies are good. I also heard that most ingredients comes from China? Is that true? Thanks


Unfortunately, I can't.

However, I always recommend looking for products that have either of the following two endorsements.

The first, is the Consumer Lab seal of approval, which means they have been tested by a independent lab and passed the testing

http://www.consumerlab.com/images/template_cl_logo.jpg

The second is the USP-Verified seal, which means is has met the quality criteria of the USP

http://www.usp.org/images/dsvp_mark.gif

And here is a list of supplements that passed the USP testing

http://www.usp.org/USPVerified/dietaryS ... ments.html


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Postby karin_kiwi » Fri Jul 04, 2008 5:10 am

I'm not sure if you can answer this. I live in New Zealand - you know, where there's a big hole in the ozone layer and the melanoma rate is one of the highest in the world. In winter I will go outside without sunblock on. But for 4-5 months of the year I just cannot go outside between 11am-4pm (10am-5pm in the hottest couple of months) without sunblock. I will literally burn in less than 5 minutes without protection (official burn time is around 7 minutes). I'm not talking a faint pink blush, but skin that is red, hot to touch even 6-10 hours later, a little painful and tight. I can burn in the NZ sun through a t-shirt, even dry. Even with 45 factor sunblock on, I can burn in an hour if I'm out in full sun.

I worry enormously about skin cancer, especially because my genetic heritage is from England and Austria/Germany - not exactly the most tropical of countries. So I stick strictly to the shade and inside for the majority of the day in late spring-early autumn. But supposedly there's a Vit D deficiency problem here, too.

Does the sunblock completely negate the potential Vit D benefits of the sun? Is it better to spend the 5 minutes getting sun on bare skin even if it means a burn? Will the sun in the early morning (e.g. 9am) or late afternoon (after 5pm) be effective? I would like to know your opinion on the relative risk of Vit D deficiency and sunburn/UV exposure.
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