tag:blogger.com,1999:blog-8859456735165996893.post3576147238778134179..comments2024-03-28T02:36:04.078-07:00Comments on Health Correlator: What is a reasonable vitamin D level?Ned Kockhttp://www.blogger.com/profile/02755560885749335053noreply@blogger.comBlogger72125tag:blogger.com,1999:blog-8859456735165996893.post-28603210042127405482011-03-07T01:14:31.344-08:002011-03-07T01:14:31.344-08:00Good information I like it so much.....
Smith AL...Good information I like it so much.....<br /><br /><br />Smith ALanviagra onlinehttp://www.raymeds.comnoreply@blogger.comtag:blogger.com,1999:blog-8859456735165996893.post-37918977549657461002010-12-20T12:57:26.638-08:002010-12-20T12:57:26.638-08:00By the way, Chris K and others, one of the contrib...By the way, Chris K and others, one of the contributors to interindividual variation in response of 25(OH)D to dietary D is going to be adiposity. People with more adipose tissue will require more D to lead to the same increase in 25(OH)D.<br /><br />ChrisChris Masterjohnhttps://www.blogger.com/profile/09922003080748568167noreply@blogger.comtag:blogger.com,1999:blog-8859456735165996893.post-64413589997434595282010-12-19T14:27:14.154-08:002010-12-19T14:27:14.154-08:00Oh and here is one interesting paper on vitamin D ...Oh and here is one interesting paper on vitamin D & vitamin K synergy:<br /><br />http://www.thorne.com/altmedrev/.fulltext/15/3/199.pdfNeonomidehttps://www.blogger.com/profile/00961709424324961929noreply@blogger.comtag:blogger.com,1999:blog-8859456735165996893.post-30320473004633672532010-12-17T23:01:22.196-08:002010-12-17T23:01:22.196-08:00A Cochrane Review found that vitamin A supplements...A Cochrane Review found that vitamin A supplements increased total mortality rate by 16%, perhaps through antagonism of vitamin D<br /><br />http://www.ncbi.nlm.nih.gov/pubmed/18425980<br /><br /><br />Of course, supplements are not food.<br /><br />My reasonable vitamin D level seems to be around 100 nmol/l and 50-100 µg day, at the moment. My Crohn's is simply almost symptomless at that dose.<br /><br />McGill unversity researchers found that the vitamin D has a direct impact on two genes that have been linked to Crohn’s disease, beta-defensin and NOD2. Vitamin D directly impacts the beta defensin 2 gene, which then encodes a specific peptide, and the NOD2 gene that lets cells know that invading microbes are present. If NOD2 is deficient or defective, it cannot fight the invaders in the intestinal tract. If patients have an adequate amount of vitamin D, this breakdown may be prevented and inflammation may be reduced. <br /><br />http://www.sciencedaily.com/releases/2010/01/100127104904.htm<br /><br /><br />Of course, Vitamin D has already prevented flare ups in a small controlled study (P = 0.06):<br /><br />http://www.ncbi.nlm.nih.gov/pubmed/20491740<br /><br />My guess is that 96 nmol/l is not enough and base levels were a LOT higher than Crohn's patients normally have. Also, as a clinical dose, 50 µg is a joke. Much larger doses have been used in Multiple Schlerosis patients and generally D3 rocked.<br /><br />Sorry Jenny, I'm a believer. My BP also dropped like a stone, to around 115/65 first time in my life. I get periodical serum calcium tests too, and I had normal calcium even when taking 200 µg a day. As a semi-paleo, my calcium intake wasn't a lot I must say.<br /><br />I happen to be finnish (62 degrees north, a bit south from Fort Yukon in Alaska by comparison), so my/our base values were around 20-25 nmol/l less than US ones, which should be taken into account.<br /><br />As an anecdote, I tried to get a tan several 4-6 times a week during (a very hot) summer full frontal during mid-day, yet still my Crohn's reacted clearly better to D3 supplements in spring & autumn.Neonomidehttps://www.blogger.com/profile/00961709424324961929noreply@blogger.comtag:blogger.com,1999:blog-8859456735165996893.post-85205310551671762292010-12-17T10:10:07.845-08:002010-12-17T10:10:07.845-08:00Here's a provocative article just published th...Here's a provocative article just published that suggests optimum breast-cancer prevention requires both sunlight and supplementation. Strictly observational, of course:<br /><br />http://cebp.aacrjournals.org/content/early/2010/12/01/1055-9965.EPI-10-1039.abstract?sid=14f3ca06-f78f-4f8d-b169-5fbe7f2f62be<br /><br />Can't get to more than the abstract. There are some quotes from the main text embedded in this pop-sci article:<br /><br />http://www.nutraingredients-usa.com/Research/Supplements-and-sunlight-give-optimal-protection-from-breast-cancer-Study?utm_source=AddThisWeb&utm_medium=SocialAddThis&utm_campaign=SocialMediaDavid Isaakhttps://www.blogger.com/profile/04928598446742324391noreply@blogger.comtag:blogger.com,1999:blog-8859456735165996893.post-23706257936625922342010-12-17T07:53:17.434-08:002010-12-17T07:53:17.434-08:00Hi Ned - my TC levels are normally in the 7's ...Hi Ned - my TC levels are normally in the 7's (HDL is upper 2's and now 3, trigs 0.6) so I wonder if that's an explanation for the easy way I make 25(OH)D.<br /><br />I should add that when my 25(OH)D went up to 384 nmol/L it did not cause any problems at all, everything else, calcium etc, stayed absolutely normal.Annehttps://www.blogger.com/profile/07160051347588051524noreply@blogger.comtag:blogger.com,1999:blog-8859456735165996893.post-63616114755997973162010-12-17T06:50:42.944-08:002010-12-17T06:50:42.944-08:00Hi Anne. The participant with the highest 25D incr...Hi Anne. The participant with the highest 25D increase also had one of the highest TC levels in the group: approximately 5.5 mmol/. (As you can see, the TC levels were not that high in this group.) That person had an increase of 50 nmol/l in 25D.Ned Kockhttps://www.blogger.com/profile/02755560885749335053noreply@blogger.comtag:blogger.com,1999:blog-8859456735165996893.post-39629139672332034932010-12-17T06:50:17.026-08:002010-12-17T06:50:17.026-08:00Hi David.
There are researchers who think that v...Hi David. <br /><br />There are researchers who think that vitamin D production from sunlight comes with a few co-factors that are fairly important for health. The co-factors are also produced endogenously based on the same stimulus, namely sunlight. <br /><br />Dr Holick is one of those researchers. Two blog posts reviewed his research (published in a book) below, by Dr. Eades:<br /><br />http://www.proteinpower.com/drmike/supplements/sunshine-superman/<br /><br />http://www.proteinpower.com/drmike/supplements/heliophobe-madness/Ned Kockhttps://www.blogger.com/profile/02755560885749335053noreply@blogger.comtag:blogger.com,1999:blog-8859456735165996893.post-14185925100050447172010-12-16T23:38:53.476-08:002010-12-16T23:38:53.476-08:00"The correlation between total cholesterol an..."The correlation between total cholesterol and 25D is reasonably strong and clearly statistically significant. It is 0.515, based on the R-squared of 0.265 that they provided."<br /><br />I wasn't able to access the full study and it would be interesting to know the figures. As I wrote before my 25(OH)D is always between 125 and 200 nmol/L on only 1500 IU D3 per day and went up to 384 nmol/L on 4,000 IU per day. My total cholesterol is high !Annehttps://www.blogger.com/profile/07160051347588051524noreply@blogger.comtag:blogger.com,1999:blog-8859456735165996893.post-61384958715001997052010-12-16T17:09:01.338-08:002010-12-16T17:09:01.338-08:00I'm not an albino, but I could easily play one...I'm not an albino, but I could easily play one on TV. I never tan. Burn, yes, quite easily, but the skin promptly peels off to reveal skin any Victorian girl would have killed for. (Well, if it weren't so hairy.)<br /><br />But I digress. Ted, Chris, Ned--thanks for all the brainfood.<br /><br />There's two reasons I asked about lamps. One is that there appears to be a feedback mechanism in sun exposure that seems to be absent from dietary supplements.<br /><br />The second is that I read the post BigWhiskey listed:<br /><br />http://healthjournalclub.blogspot.com/2010/12/sulfur-and-your-health.html<br /><br />To tell the truth, I can't tell if the points made in that post really hold water. But it made me wonder if there is a real difference between endogenous and exogenous Vitamin D...David Isaakhttps://www.blogger.com/profile/04928598446742324391noreply@blogger.comtag:blogger.com,1999:blog-8859456735165996893.post-64316716046725459032010-12-16T15:08:47.158-08:002010-12-16T15:08:47.158-08:00Hi Ned,
I agree the correlation is clearly statis...Hi Ned,<br /><br />I agree the correlation is clearly statistically significant, but it is not clear to me whether the correlation is independent of other factors. In other words, if it largely dependend on baseline 25(OH)D then all it would mean would be that the less D you need, the less you make.<br /><br />I agree the journal is not likely to publish nonsense, and I think that is why they published a letter extensively refuting the interpretation. <br /><br />They also published another letter extensively refuting the lack of connection to skin pigmentation, showing that these authors used shorter-length UV than is found in daylight, and for physiological reasons their results differ from those of previous studies and from what occurs during exposure to true sunlight.<br /><br />So, while this study may be well conducted and provide controversial findings, and thus be of interest to publish, the interpretation is challenged by the letters published alongside it and the strong evidence contained therein.<br /><br />ChrisChris Masterjohnhttps://www.blogger.com/profile/09922003080748568167noreply@blogger.comtag:blogger.com,1999:blog-8859456735165996893.post-88296500249546831312010-12-16T14:57:05.448-08:002010-12-16T14:57:05.448-08:00Chris (M.), I was going to ask you for your take o...Chris (M.), I was going to ask you for your take on the Bogh et al. article (linked by Ted), but I see you provided it above. We cannot blame the study for lack of addressing fundamental issues eh? <br /><br />The full text PDF is here, for anyone interested:<br /><br />http://www.nature.com/jid/journal/v130/n2/pdf/jid2009323a.pdf<br /><br />The correlation between total cholesterol and 25D is reasonably strong and clearly statistically significant. It is 0.515, based on the R-squared of 0.265 that they provided.<br /><br />The journal where the article was published (Journal of Investigative Dermatology) has a fairly solid citation impact – on average, a little over 120 citations per article. It doesn’t seem like the type of outlet that would publish implausible nonsense … but one never knows.Ned Kockhttps://www.blogger.com/profile/02755560885749335053noreply@blogger.comtag:blogger.com,1999:blog-8859456735165996893.post-41257062022532057722010-12-16T14:56:04.812-08:002010-12-16T14:56:04.812-08:00Ted, thanks for the link to the Bogh et al. articl...Ted, thanks for the link to the Bogh et al. article. Very interesting. Supports your point, and also confirmed some of my suspicions.<br /><br />I’ve always felt that skin pigmentation was a protection that was not supposed to limit vitamin D production from the sun.<br /><br />I thought it was funny that the authors used the term “non-sun worshippers”.Ned Kockhttps://www.blogger.com/profile/02755560885749335053noreply@blogger.comtag:blogger.com,1999:blog-8859456735165996893.post-19328752680246373792010-12-16T14:55:29.143-08:002010-12-16T14:55:29.143-08:00Assuming that 7-dehydrocholesterol and cholesterol...Assuming that 7-dehydrocholesterol and cholesterol levels are correlated, one would expect low cholesterol levels to also reflect low 7-dehydrocholesterol levels. But that’s a guess on my part.Ned Kockhttps://www.blogger.com/profile/02755560885749335053noreply@blogger.comtag:blogger.com,1999:blog-8859456735165996893.post-89419197384625720702010-12-16T14:55:14.257-08:002010-12-16T14:55:14.257-08:00I generally agree with Ted regarding lamps. Very g...I generally agree with Ted regarding lamps. Very good points.Ned Kockhttps://www.blogger.com/profile/02755560885749335053noreply@blogger.comtag:blogger.com,1999:blog-8859456735165996893.post-62151476733554663202010-12-16T14:06:48.219-08:002010-12-16T14:06:48.219-08:00Thanks, Ted. I hadn't seen that paper. They ...Thanks, Ted. I hadn't seen that paper. They cite a biochemistry textbook for their explanation that cholesterol is oxidized in the gut to 7-DCH, which is transported to the skin and converted to vitamin D. This does not make much sense in explaining a relationship to circulating total cholesterol rather than circulating 7-DCH. In any case, the letter by Glossman explains why this theory is completely implausible and to their knowledge not supported by any evidence, whereas they cite numerous pieces of evidence of why it is almost certainly not the case. <br /><br />For lack of time, I did not read the whole paper, but I keyword searched the pdf for "cholesterol" and I could not find any place where they indicated they looked for a correlation between 25(OH)D and cholesterol or performed any statistical analysis to see if the relationship they found between baseline total cholesterol and 25(OH)D production was independent of baseline 25(OH)D. That makes me skeptical that the relationship is meaningful. However, if it is meaningful, it almost certainly reflects a third factor influencing HMG CoA reductase activity or LDL receptor activity in the liver and also influencing 7-DCH production in the skin, and not an actual causal effect of blood cholesterol levels on vitamin D production.<br /><br />The correlation is pretty modest, r^2=~25%. Although I find the study interesting, I do not find it very convincing evidence that blood cholesterol levels have a causal effect on the potential for vitamin D production.<br /><br />ChrisChris Masterjohnhttps://www.blogger.com/profile/09922003080748568167noreply@blogger.comtag:blogger.com,1999:blog-8859456735165996893.post-39273399144592274822010-12-16T13:24:50.771-08:002010-12-16T13:24:50.771-08:00Vitamin D production after UVB exposure depends on...<a href="http://www.ncbi.nlm.nih.gov/pubmed/19812604" rel="nofollow">Vitamin D production after UVB exposure depends on baseline vitamin D and total cholesterol but not on skin pigmentation.</a>TedHutchinsonhttps://www.blogger.com/profile/13140097526458431747noreply@blogger.comtag:blogger.com,1999:blog-8859456735165996893.post-31447913492333402402010-12-16T11:53:38.956-08:002010-12-16T11:53:38.956-08:00Vitamin D is not made from cholesterol; it is made...Vitamin D is not made from cholesterol; it is made from 7-dehydrocholesterol, a precursor to cholesterol. As far as I know, the 7-DHC is believed to be made locally in the skin, so I'm not sure what low blood cholesterol would tell you.<br /><br />ChrisChris Masterjohnhttps://www.blogger.com/profile/09922003080748568167noreply@blogger.comtag:blogger.com,1999:blog-8859456735165996893.post-62495839188100185292010-12-16T11:50:57.716-08:002010-12-16T11:50:57.716-08:00@ does anyone think that sunlamps might be better ...@<i> does anyone think that sunlamps might be better than supplements?</i><br />Depends I'm not keen on UVA and many commercial Tanning studios have high UVA outputs. The Vitamin D council offer Mercola's and Sperti so they may be worth considering. At least at home you can keep track of usage, most UVB tubes decline in UVB output over 500~800hrs.<br />Do bear in mind Vitamin D is made from cholesterol near surface of skin. Low cholesterol means potential for making Vit d is limited, partly why vitamin D production from sun/uvb declines with age. <br />Also remember the <a href="http://www.biomedcentral.com/1755-8794/2/2%22" rel="nofollow">damage to skin by UVA</a> may be increased by iron see also <a href="http://www.biomedcentral.com/1755-8794/2/2%22" rel="nofollow">Iron Behaving badly</a><br />So before UVA exposure it's worth improving your natural sunscreen photoprection potential by increasing anti-oxidant status with natural iron chelators such as Curcumin, Quercetin, resveratrol, melatonin, green tea, lycopene but remember it takes time for these approaches to become effective so take the UV exposure very slowly and carefully. <br />I don't have to remind you to NEVER GET BURNT.<br /> Don't give up on some oral D3.<br />I think it's possible vitamin d may have a direct impact on pathogenic, obesogenic gut flora. <br /><a href="http://www.sciencedaily.com/releases/2010/07/100707141558.htm" rel="nofollow">Amid the Murk of 'Gut Flora,' Vitamin D Receptor Emerges as a Key Player</a>TedHutchinsonhttps://www.blogger.com/profile/13140097526458431747noreply@blogger.comtag:blogger.com,1999:blog-8859456735165996893.post-49257167429247520822010-12-16T10:54:08.661-08:002010-12-16T10:54:08.661-08:00As long as we're on the topic, does anyone thi...As long as we're on the topic, does anyone think that sunlamps might be better than supplements?David Isaakhttps://www.blogger.com/profile/04928598446742324391noreply@blogger.comtag:blogger.com,1999:blog-8859456735165996893.post-24340651222230296492010-12-16T06:58:07.730-08:002010-12-16T06:58:07.730-08:00Chris--
I've read Volek's stuff, and it&#...Chris--<br /><br />I've read Volek's stuff, and it's good. But the low-carb vs low-fat debate has been at high volume since the 1970s, and we are only now beginning to get a handful of studies done on the topic.<br /><br />I don't think that nutrition research studies are particularly underfunded overall. But I think the money is allocated largely to attempts to find proof for the pre-existing belief systems of a coterie of researchers who have dominated the field since the days of Ancel Keys--pretty much the opposite of the way science is supposed to be done.David Isaakhttps://www.blogger.com/profile/04928598446742324391noreply@blogger.comtag:blogger.com,1999:blog-8859456735165996893.post-60387055034814665912010-12-16T06:43:57.653-08:002010-12-16T06:43:57.653-08:00Thanks for the link BigWhiskey.Thanks for the link BigWhiskey.Ned Kockhttps://www.blogger.com/profile/02755560885749335053noreply@blogger.comtag:blogger.com,1999:blog-8859456735165996893.post-74615105299801967062010-12-16T06:42:39.938-08:002010-12-16T06:42:39.938-08:00Hi David. One of the reasons why I like to look at...Hi David. One of the reasons why I like to look at old medical/nutrition studies is that they often address much more fundamental questions than newer ones.Ned Kockhttps://www.blogger.com/profile/02755560885749335053noreply@blogger.comtag:blogger.com,1999:blog-8859456735165996893.post-66510501914333539762010-12-16T06:42:15.719-08:002010-12-16T06:42:15.719-08:00Hey Chris. Of course you didn’t offend me. You alw...Hey Chris. Of course you didn’t offend me. You always present your points of view in a very polite and convincing way. I was just joking. I like challenging arguments.<br /><br />By the way, I studied law for a while (for about year, eons ago) and almost decided to pursue that career at some point; maybe I would have been a good litigator myself.<br /><br />And I am a big fan of the old "Law & Order" series, with Sam Waterston playing the role of ADA Jack McCoy. You remind me of him a bit :)Ned Kockhttps://www.blogger.com/profile/02755560885749335053noreply@blogger.comtag:blogger.com,1999:blog-8859456735165996893.post-71014989826071661732010-12-15T23:35:26.460-08:002010-12-15T23:35:26.460-08:00David,
Volek is doing good low-carb studies at UC...David,<br /><br />Volek is doing good low-carb studies at UConn.<br /><br />For vitamin D, there's lots of research going on, and the new IOM report will stimulate dose-finding RCTs as well as funding for them.<br /><br />I agree about underfinding and underresourcing of nutritional research in general.<br /><br />ChrisChris Masterjohnhttps://www.blogger.com/profile/09922003080748568167noreply@blogger.com