80 replies to this topic

[Athanasios]

There's lots of rodent data showing the harm of excessive vitamin d.

Sure, but the amount of Vit D3 that is considered excessive in humans is the argument.

Here are some quotes from the article you posted:

"Since our study only looked at diet and brain lesions at one point in time, we cannot conclude that calcium or vitamin D caused the brain lesions that we found,"

and

"You wouldn't want to change your intake of calcium and vitamin D based on this study," she advised. "It may generate some hypotheses that are worth testing, but at this point the research can't really speak to whether the brain lesions were related to the calcium, vitamin D, or some other factor that people with high intakes of calcium and vitamin D also have."

Was dietary Vit D2 in milk? How much sun did they get? Was there a correlation with serum levels? Was high Vit D or high calcium alone significant? Etc.

Vieth puts forth quite a few studies that show the safety of Vit D3 in humans, why look at vague or knockout rat data, studies that look at multi-variables that compound the problem, studies that do not specify the amount or kind of vit D used, etc?

[DukeNukem]

A key to taking D3 is also taking calcium, magnesium and K2. From all that I've read, I see all of those as synergistic, and all required to keep things in balance. I recently started taking a lot more K2, in fact, adding one of these to my daily regimen:
http://relentlessimp...natetrenone.htm

[mitkat]

A key to taking D3 is also taking calcium, magnesium and K2.  From all that I've read, I see all of those as synergistic, and all required to keep things in balance.  I recently started taking a lot more K2, in fact, adding one of these to my daily regimen:
http://relentlessimp...natetrenone.htm

I've been taking the last of my 400 IU vitamin D3's with a couple of AOR Ortho-Minerals (which also contain some D3), as it does seem there's lots of mineral synergism going on.

[browser]

My dosage as of now is 4800IU i take one 2400IU in the am and one in the pm, does anyone know if splitting them up is necessary or taking them both at same time yields same results?

According to my directions on my LEF 5,000 IU (not a plug for the product), the directions say to take once a day with a fat containing, low fiber meal. Fat containing means it's soluble in fats/oils and low fiber implies that it, like cholesterol, will be carried out through the gut by fiber. I take my LEF mix (not a plug) tablets take 3 times a day as directed. I take my D3 with my mid day meal, the only full meal I take (I follow the Ayurvedic approach to eating for my body type, which is once a day during the hotest part of the day and it's now 85 degrees F where I am right now). My other "meals" are coffee with cocoa and a fruit smoothy for breadfast, a big glass of vegetable juices in the evening. Basically morning and evening liquid meals are to go with my supplements. My evening vegetable juice is followed by a couple glasses of red wine with a blueberry/pomegranate capsule (I take one in the morning as well). I add some blueberry/pomegranate juice to the wine.

[krillin]

Here are some quotes from the article you posted:

That's boilerplate that every scientist uses. More research always has to be done, or else why should they receive more funding? They also want to have zero risk of saying something that might turn out to be wrong. Vitamin consumers don't have careers or credibility at stake, so we should conclude that common vitamin D intakes can be dangerous and need to be careful.

There's so much individual variability with vitamin D that the only rational thing to do is keep under the lowest reported harmful dose unless you have blood tests to guide you. It's foolish to be like Vieth and accuse Narang et al. of having "grossly underestimated the amount of vitamin D in the doses they used." It's foolish to see the brain lesions and say that it can't happen to me, it was the calcium. If I blindly followed Vieth I'd be taking 4 times as much as I need.

3000 IU was too much for this person.

http://sunlightandvi.....mple Chapters

A woman with severe osteoporosis, demonstrating a lumbar SD -4.6 and low 25(OH)D began taking D3, cholecalciferol, 3,000 IU a day. Her serum 25(OH)D rose from below 20 ng/ml to 42 ng/ml within 4 months and a follow up bone scan after 8 months of D supplementation showed some not significant (very slight) bone gain had occurred. The client did not want the expense of testing, it was not supported by her physician or HMO, so did not test D again. She continued to take the original 3,000 IU of D about five days a week. This dose is slightly lower than the dose of 4,000 IU sometimes suggested or used by some D researchers and clinicians. She also took between 1,000-1,500 mg calcium in addition to food sources and did not avoid foods containing D. The next bone scan, about 1 year after the scan showing a slight gain and 2 years after starting vitamin D, showed normal PTH (43 ng/ml); 25(OH)D 95 ng/ml; and lumbar SD -4.8 in addition to more loss in the femur for SD -2.2 to -2.5. Overall she experienced a 6% loss of bone density.

http://www.westonapr...indmiracle.html

In my practice, I am discovering that some people may need upwards of 4,000 IU daily to maintain optimal blood levels. Others may find that anything over 200-400 IU puts them in a situation of overdose.

[quarter]

Does anyone know if it easy to get tests for such things as Viatmin D levels on the UK NHS?

I am thinking the doctor might think I am wasting tax payers money if I make an appointment and ask for these tests when then is nothing apparently wrong with me.

Does anyone here from the UK get their levels of these things tested? If so, where and how?

[Athanasios]

3000 IU was too much for this person.

I can't stress enough the importance of controlled trials.

[krillin]

3000 IU was too much for this person.

I can't stress enough the importance of controlled trials.

They're important at the level of deciding on a uniform amount to feed your population to keep enough of them healthy. Remember, the RDAs were introduced during World War II because of the terrible condition of the draftees. If the RDA is inappropriate for a few percent of the population, big deal. There's more where they came from.

At the level of deciding what's best for an individual, ignore the echo chamber in here and get a blood test. I could understand poo pooing the risk if you were addressing the great unwashed masses who won't bother to get tested. On average, thousands of IUs would be good for the population. Lots would be helped, a smaller number would suffer. I don't see why any of the elite folks here would want to risk being part of the group that suffers. I didn't, so I got tested and found that 1000 IU puts me in the optimal zone. But it wasn't part of a clinical trial so you'll probably be ignoring that data point too.

"A single death is a tragedy; a million deaths is a statistic."

[krillin]

Does anyone know if it easy to get tests for such things as Viatmin D levels on the UK NHS?

I am thinking the doctor might think I am wasting tax payers money if I make an appointment and ask for these tests when then is nothing apparently wrong with me.

Does anyone here from the UK get their levels of these things tested? If so, where and how?

Maybe get in touch with this doctor. Vitamin D isn't on her list, but she says she can look into getting other tests ordered. Disclaimer: I came across her site in a web search and have no first- or second-hand knowledge about her.

http://www.drmyhill....index.cfm?id=11
http://www.drmyhill.co.uk/tests.cfm

[Athanasios]

In a trial at least the dosage can be confirmed and supplemental calcium and other factors ruled out. Whereas in the anecdotal report that is not the case.

I didn't, so I got tested and found that 1000 IU puts me in the optimal zone. But it wasn't part of a clinical trial so you'll probably be ignoring that data point too.

Sure, thats great, but would 4000IU put you at dangerous levels? Or even less than optimal?

[Matt]

4000IU would NOT be dangerous for almost everyone...

Don't we get something like 10,000 - 20,000 from just half hour out in the sun!

280,000 IU of Vitamin D3 per week resulted in no problems here:


See this study


Samantha M Kimball, Melanie R Ursell, Paul O'Connor and Reinhold Vieth
Safety of vitamin D3 in adults with multiple sclerosis1,2,3

Background: Vitamin D3 may have therapeutic potential in several diseases,
including multiple sclerosis. High doses of vitamin D3 may be required for
therapeutic efficacy, and yet tolerability-in the present context, defined
as the serum concentration of 25-hydroxyvitamin D [25(OH)D] that does not
cause hypercalcemia-remains poorly characterized.

Objective: The objective of the study was to characterize the calcemic
response to specific serum 25(OH)D concentrations.

Design: In a 28-wk protocol, 12 patients in an active phase of multiple
sclerosis were given 1200 mg elemental Ca/d along with progressively
increasing doses of vitamin D3: from 700 to 7000 µg/wk (from 28 000 to 280
000 IU/wk).

Results: Mean (± SD) serum concentrations of 25(OH)D initially were 78 ± 35
nmol/L and rose to 386 ± 157 nmol/L (P < 0.001). Serum calcium
concentrations and the urinary ratio of calcium to creatinine neither
increased in mean values nor exceeded reference values for any participant
(2.1-2.6 mmol/L and <1.0, respectively). Liver enzymes, serum creatinine,
electrolytes, serum protein, and parathyroid hormone did not change
according to Bonferroni repeated-measures statistics, although parathyroid
hormone did decline significantly according to the paired t test. Disease
progression and activity were not affected, but the number of
gadolinium-enhancing lesions per patient (assessed with a nuclear magnetic
brain scan) decreased from the initial mean of 1.75 to the end-of-study mean
of 0.83 (P = 0.03).

Conclusions: Patients' serum 25(OH)D concentrations reached twice the top of
the physiologic range without eliciting hypercalcemia or hypercalciuria. The
data support the feasibility of pharmacologic doses of vitamin D3 for
clinical research, and they provide objective evidence that vitamin D intake
beyond the current upper limit is safe by a large margin

[krillin]

In a trial at least the dosage can be confirmed and supplemental calcium and other factors ruled out. Whereas in the anecdotal report that is not the case.

Your thinking is backwards. We should heed the warning until it's proven false by a blood test, not ignore the warning until it's proven true by adverse effects.

I didn't, so I got tested and found that 1000 IU puts me in the optimal zone. But it wasn't part of a clinical trial so you'll probably be ignoring that data point too.

Sure, thats great, but would 4000IU put you at dangerous levels? Or even less than optimal?

Finding out would entail incurring risk for no plausible benefit. Why did you concede that testing was a good idea, anyway, if you don't think thousands of IUs can be a problem? If there's no risk, why waste the $50 or so? Just think of all the cigars you could buy with that money.

[krillin]

280,000 IU of Vitamin D3 per week resulted in no problems here:

386 nmol/L is dangerous.

Eur J Epidemiol. 2001;17(6):567-71.
Comment in: Eur J Epidemiol. 2003;18(5):461-2.
Serum 25-hydroxyvitamin D3 levels are elevated in South Indian patients with ischemic heart disease.
Rajasree S, Rajpal K, Kartha CC, Sarma PS, Kutty VR, Iyer CS, Girija G.

Department of Cardiology and Achutha Menon Centre for Health Science Studies, Sree Chitra Tirunal Institute for Medical Sciences and Technology, Trivandrum, India.

Several lines of evidence point to a possible relationship between vitamin D and cardiovascular disease. Animal experiments and observational studies in humans suggest vitamin D to be arteriotoxic and an association of high intake of vitamin D with increased incidence of ischemic heart disease (IHD). The major source of vitamin D in adults is vitamin D synthesized in the skin through exposure to the sun. In tropical environment there is a possibility of high level of solar exposure and enhanced serum levels of vitamin D in the population. We explored the relation between serum level of 25-hydroxyvitamin D3 and IHD in a case-control study involving 143 patients with either angiographic evidence of coronary artery disease or patients with acute myocardial infarction and 70 controls, all men in the age group of 45-65 years. Fasting blood samples were collected, serum separated and serum levels of 25-hydroxyvitamin D3 was measured by protein binding radioligand assay. Serum levels of cholesterol, triglyceride, calcium, magnesium and inorganic phosphate were also determined. Prevalences of diabetes, hypertension and smoking history were noted. Statistical comparisons of variables between cases and controls were done using chi2-tests. Multivariate logistic regression analysis was done to examine the association of IHD with serum levels of 25-hydroxyvitamin D3 controlling for selected variables. Serum levels of 25-hydroxyvitamin D3, calcium, inorganic phosphate, total cholesterol, low density lipoprotein and triglycerides were elevated in a higher proportion of patients, compared to controls. Serum levels of 25-OH-D3 above 222.5 nmol/l (89 ng/ml) was observed in 59.4% of cases compared to 22.1% in controls (p < 0.001; unadjusted odds ratio (OR): 5.17; 95% confidence interval (CI): 2.62-10.21). When controlled for age and selected variables using the multivariate logistic regression, the adjusted OR relating elevated serum 25-hydroxyvitamin D3 levels (> or = 222.5 nmol/l, > or = 89 ng/ml) and IHD is 3.18 (95% CI: 1.31-7.73). Given the evidences for the arteriotoxicity of vitamin D, further investigations are warranted to probe whether the elevated serum levels of 25-hydroxyvitamin D3 observed in patients with IHD in a tropical environment has any pathogenic significance.

PMID: 11949730

[Athanasios]

Your thinking is backwards. We should heed the warning until it's proven false by a blood test, not ignore the warning until it's proven true by adverse effects.

The warning itself has been successfully argued against by Vieth. That was the point of my first post in this thread.

Finding out would entail incurring risk for no plausible benefit

You can find out by ( http://jn.nutrition..../full/135/2/317 ):

The data show that for every 40 IU of vitamin D intake, circulating 25(OH)D increases by 0.70 nmol/L (0.28 µg/L) over 5 mo on a given regimen. A steady state appears to be achieved after ~90 d on each dose tested (23,38). Thus, doses of 400, 1000, 5000, and 10,000 IU/d for 5 mo will result in theoretical increases in circulating concentrations of 7, 17.5, 70, and 175 nmol 25(OH)D, respectively.

This means you would add about 50nmol/L to your current status.

Why did you concede that testing was a good idea, anyway, if you don't think thousands of IUs can be a problem? If there's no risk, why waste the $50 or so? Just think of all the cigars you could buy with that money.

Because I think it important to know if you are undershooting the optimal.

Have you found any data showing that < 200nmol/L can be damaging? It would be new info to me and I would be given more pause.

[Matt]

386 nmol/L is dangerous.

Well I wouldn't exactly take that much, but I'll stick to 5000 IU per day as I see no harm in this amount.

I've read a bit of this study, see what you think

Randomized comparison of the effects of the vitamin D3 adequate intake versus 100 mcg (4000 IU) per day on biochemical responses and the wellbeing of patients
http://www.pubmedcen...bmedid=15260882

[browser]

386 nmol/L is dangerous.

Well I wouldn't exactly take that much, but I'll stick to 5000 IU per day as I see no harm in this amount.

I've read a bit of this study, see what you think

Randomized comparison of the effects of the vitamin D3 adequate intake versus 100 mcg (4000 IU) per day on biochemical responses and the wellbeing of patients
http://www.pubmedcen...bmedid=15260882

Additionally, there's hardly a drug your doctor will dispense for you that doesn't have dire side effects in some small subset of the populace. Add to that food allergies. I was put off by all the FUD about hypercalcemia, but I'm taking my LEF 5,000 IU with my single large meal of the day nonetheless.

[krillin]

The warning itself has been successfully argued against by Vieth.  That was the point of my first post in this thread.

No he didn't. All he did was say that his data conflicts with other people's data, so theirs is obviously wrong. Life isn't that simple. Why is it so hard for some people to understand the concept of biochemical individuality?

The data show that for every 40 IU of vitamin D intake, circulating 25(OH)D increases by 0.70 nmol/L (0.28 µg/L) over 5 mo on a given regimen. A steady state appears to be achieved after ~90 d on each dose tested (23,38). Thus, doses of 400, 1000, 5000, and 10,000 IU/d for 5 mo will result in theoretical increases in circulating concentrations of 7, 17.5, 70, and 175 nmol 25(OH)D, respectively.

This means you would add about 50nmol/L to your current status.

No, it would add 50 nmol/L to the status of the people studied. I'm different. I spend little time outdoors after sunrise and took the test in April, so there's probably negligible solar D contribution. I don't consume milk or fish, so my 1000 IU supplement thus got me to 45.1 ng/ml. Going with your linear assumption, 4000 IU would get me to a maximum of 180.4 ng/ml, or 451 nmol/l. To find a lower bound, let's say that I somehow got the RDA from the sun. 1000 IU thus contributed 32.2, so 4000 IU would bring me to 141.7 ng/ml, or 354 nmol/l.

Have you found any data showing that < 200nmol/L can be damaging? It would be new info to me and I would be given more pause.

I haven't seen anything. The consensus seems to be that 40-50 ng/ml is best, and 80 or above is in the toxic range. Davis aims for 50, and confirms that there are others like me. a rare person requires only 1000 IU per day

The nutritionist I cited above says that 65 or above can be toxic for some people, based on her practice. As more people start drinking the vitamin D Kool-Aid, I'm sure we'll eventually have some studies come out that determine the level that increases long-term risk without causing any acute harm.

[krillin]

Krillin's demand for a vitamin D mortality U-curve has been met.

Arch Intern Med. 2008 Aug 11;168(15):1629-37.
25-hydroxyvitamin D levels and the risk of mortality in the general population.
Melamed ML, Michos ED, Post W, Astor B.
Division of Nephrology, Department of Medicine, Albert Einstein College of Medicine, 1300 Morris Park Ave, Ullmann 615, Bronx, NY 10461, USA. mmelamed@aecom.yu.edu

BACKGROUND: In patients undergoing dialysis, therapy with calcitriol or paricalcitol or other vitamin D agents is associated with reduced mortality. Observational data suggests that low 25-hydroxyvitamin D levels (25[OH]D) are associated with diabetes mellitus, hypertension, and cancers. However, whether low serum 25(OH)D levels are associated with mortality in the general population is unknown. METHODS: We tested the association of low 25(OH)D levels with all-cause, cancer, and cardiovascular disease (CVD) mortality in 13 331 nationally representative adults 20 years or older from the Third National Health and Nutrition Examination Survey (NHANES III) linked mortality files. Participant vitamin D levels were collected from 1988 through 1994, and individuals were passively followed for mortality through 2000. RESULTS: In cross-sectional multivariate analyses, increasing age, female sex, nonwhite race/ethnicity, diabetes, current smoking, and higher body mass index were all independently associated with higher odds of 25(OH)D deficiency (lowest quartile of 25(OH)D level, <17.8 ng/mL [to convert to nanomoles per liter, multiply by 2.496]), while greater physical activity, vitamin D supplementation, and nonwinter season were inversely associated. During a median 8.7 years of follow-up, there were 1806 deaths, including 777 from CVD. In multivariate models (adjusted for baseline demographics, season, and traditional and novel CVD risk factors), compared with the highest quartile, being in the lowest quartile (25[OH]D levels <17.8 ng/mL) was associated with a 26% increased rate of all-cause mortality (mortality rate ratio, 1.26; 95% CI, 1.08-1.46) and a population attributable risk of 3.1%. The adjusted models of CVD and cancer mortality revealed a higher risk, which was not statistically significant. CONCLUSION: The lowest quartile of 25(OH)D level (<17.8 ng/mL) is independently associated with all-cause mortality in the general population.

PMID: 18695076

Attached Files

•  Vitamin_D_U_Curve.bmp   576.05KB   151 downloads

[Jay]

Krillin's demand for a vitamin D mortality U-curve has been met.

Arch Intern Med. 2008 Aug 11;168(15):1629-37.
25-hydroxyvitamin D levels and the risk of mortality in the general population.
Melamed ML, Michos ED, Post W, Astor B.
Division of Nephrology, Department of Medicine, Albert Einstein College of Medicine, 1300 Morris Park Ave, Ullmann 615, Bronx, NY 10461, USA. mmelamed@aecom.yu.edu

BACKGROUND: In patients undergoing dialysis, therapy with calcitriol or paricalcitol or other vitamin D agents is associated with reduced mortality. Observational data suggests that low 25-hydroxyvitamin D levels (25[OH]D) are associated with diabetes mellitus, hypertension, and cancers. However, whether low serum 25(OH)D levels are associated with mortality in the general population is unknown. METHODS: We tested the association of low 25(OH)D levels with all-cause, cancer, and cardiovascular disease (CVD) mortality in 13 331 nationally representative adults 20 years or older from the Third National Health and Nutrition Examination Survey (NHANES III) linked mortality files. Participant vitamin D levels were collected from 1988 through 1994, and individuals were passively followed for mortality through 2000. RESULTS: In cross-sectional multivariate analyses, increasing age, female sex, nonwhite race/ethnicity, diabetes, current smoking, and higher body mass index were all independently associated with higher odds of 25(OH)D deficiency (lowest quartile of 25(OH)D level, <17.8 ng/mL [to convert to nanomoles per liter, multiply by 2.496]), while greater physical activity, vitamin D supplementation, and nonwinter season were inversely associated. During a median 8.7 years of follow-up, there were 1806 deaths, including 777 from CVD. In multivariate models (adjusted for baseline demographics, season, and traditional and novel CVD risk factors), compared with the highest quartile, being in the lowest quartile (25[OH]D levels <17.8 ng/mL) was associated with a 26% increased rate of all-cause mortality (mortality rate ratio, 1.26; 95% CI, 1.08-1.46) and a population attributable risk of 3.1%. The adjusted models of CVD and cancer mortality revealed a higher risk, which was not statistically significant. CONCLUSION: The lowest quartile of 25(OH)D level (<17.8 ng/mL) is independently associated with all-cause mortality in the general population.

PMID: 18695076

Good post. The data gathered from this study supports your hypothesis that there is a U-curve for vitamin D supplementation. It also supports my hypothesis that there is a U-curve for being outside. Definitely worth more studies, which I suspect are already on the way.

The people studied here were not given supplements -- the authors of the study just measure blood levels of 25(OH)D. Since most people don't supplement with D (outside of what's in milk and maybe multivitamins/calcium pills -- i.e, max 600IUs/day), the people who had 25(OH)D levels above 50 probably spent most of their time outside. In forming their conclusion, the authors seem to have controlled for certain demographic factors (possibly including physical exertion), but I don't think the chart you attached does. Thus, the chart may simply show that people who are outside all of the time die more.

[FunkOdyssey]

That's an interesting point. If you think about what kind of people are both old enough to die (from anything) and would have 25OHD levels that high, physical laborers come to mind, which would bring in all of the other negative factors you might associate with people in these occupations.

[StrangeAeons]

That's an interesting point. If you think about what kind of people are both old enough to die (from anything) and would have 25OHD levels that high, physical laborers come to mind, which would bring in all of the other negative factors you might associate with people in these occupations.

1) Excluding physical laborers who work away from sunlight, i.e. miners, firefighters, warehouse and industrial laborers-- and these trend towards the more adverse work environments.
2) For all the negative factors associated with physical laborers, a sedentary lifestyle isn't one of them; so if you want to bring up confounding variables you can go either way: lower economic class therefore poorer diet and more stress, but also very physically active.
3) Did they adjust for melanoma when creating this curve?

[FunkOdyssey]

My idea was that the highest 25OHD levels may be associated with lower economic class, which is a predictor of mortality from all kinds of everything, physically active or not. This is what I came up with when thinking about groups of people 40+ years old that spend all day working outdoors.

Edited by FunkOdyssey, 09 March 2009 - 07:54 PM.

[RoadToAwe]

280,000 IU of Vitamin D3 per week resulted in no problems here:

386 nmol/L is dangerous.

Eur J Epidemiol. 2001;17(6):567-71.
Comment in: Eur J Epidemiol. 2003;18(5):461-2.
Serum 25-hydroxyvitamin D3 levels are elevated in South Indian patients with ischemic heart disease.
Rajasree S, Rajpal K, Kartha CC, Sarma PS, Kutty VR, Iyer CS, Girija G.

PMID: 11949730

The Indian study was flawed. See Vieth's response.

Attached Files

•  Vieth_Response.pdf   54.37KB   65 downloads

[krillin]

In forming their conclusion, the authors seem to have controlled for certain demographic factors (possibly including physical exertion), but I don't think the chart you attached does. Thus, the chart may simply show that people who are outside all of the time die more.

The y-axis says "adjusted all-cause mortality rate ratio (95% CI)"

Full text says

The fully adjusted model includes age, sex, race, season, hypertension, history of CVD, diabetes, smoking, high-density lipoprotein cholesterol, total cholesterol, use of cholesterol-lowering medications, estimated glomerular filtration rate categories, serum albumin level, log albumin to creatinine ratio, log C-reactive protein level, body mass index, physical activity level, use of vitamin D supplementation, and low socioeconomic status.

Edited by krillin, 10 March 2009 - 03:33 AM.

[neogenic]

With all the gene regulation (up and down), the way sun exposure works, its impact on adipose, etc. My question is this...are the acute effects from frequent doses. They say in terms of blood levels and bone health it doesn't matter whether you take 50,000IU once or 5000IUs 10 days in a row or 500IUs 100 days in a row. Thoughts?

[FunkOdyssey]

If only these studies would also track Vitamin A and Vitamin K levels, we might actually draw some useful conclusions. There seems to be rampant ignorance of the interactions between these vitamins and their consequences for health. After all the studies showing normal levels of Vitamin A increased osteoporosis (turning out to be simply a relative vitamin D deficiency), I can't help but wonder if we will make similar mistakes by looking at Vitamin D in isolation.

Edited by FunkOdyssey, 10 March 2009 - 02:50 PM.

[yoyo]

so did the study account for people taking vitamin d because they have a condition that would require it? w/o reading the study, i can't tell how they did the statistics or what they are implying wiht the conclusion

[krillin]

Disease Incidence Prevention by Serum 25(OH)D Level

Some studies show additional benefits from reaching the 50-55 ng/ml range.

[kismet]

3) Did they adjust for melanoma when creating this curve?

No, unfortunately they didn't. At least they didn't in a cancer study on the same cohort, it would be interesting to know, because vitamin D increased incidence of some unnamed types of cancers (probably including skin cancer, but how many?), while decreasing incidence of colorectal and breast cancer.

[DukeNukem]

I've been taking the last of my 400 IU vitamin D3's

Well, this is a laughably low amount. I have my two kids taking 6000IU daily. I take 10,000IU daily, and my recently measured serum level is 78 ng/ml. Perfect-o!

I STRONGLY RECOMMEND everyone watch this video presentation on vit D. This might finally convert those still in the pitiful low-dose camp to actually take a meaningful dose (and especially get their children on a dose that matters):
http://www.uvadvanta...portals/0/pres/

I've been saying for years to take at least 8000IU daily. Eventually, this will be common wisdom.