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inge
Health Professional
| Joined: | Mon Sep 25th, 2006 |
| Location: | Oslo, Norway |
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Posted: Sat Mar 15th, 2008 20:03 |
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Does anyone have a good explanation for these results, showing that 1,25 vit D is inversely correlated with obesity:
http://www.ncbi.nlm.nih.gov/pubmed/18320256
http://www.ncbi.nlm.nih.gov/pubmed/15001609
It "should" have been the other way around, shouldn't it?
Inge
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CFS/ME 125D64 25D12(dec 07) Ph1De06 daily lite exp NoIR use Ph2Mar07 ModPh2 Jun07 abx brkOct 07 r//t KFTs freq abx chg to control kidney IP Apr 08 phase 2 abx
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jcwat101
Research Professional
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Posted: Sat Mar 15th, 2008 20:25 |
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Inge,
I noticed that the second one said, that some previous studies (though small ones) had shown the reverse, so I don't think one can be sure. Also, there may be other factors.
Some obese people may spend less time outdoors exercising and such and this may have shown up more in the later studies. So part of the negative correlation they find in some of the studies (less time outside if more obese, and thus lower 25D and 1,25D), might be due to outdoor activity patterns. These correlational studies are not all that reliable and tend to vary among one another in the results they get probably related to a lot of different factors.
Joyce Waterhouse
Last edited on Sat Mar 15th, 2008 20:28 by jcwat101
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20 yrs with CFS/FM/Lyme/IBS, food sensitivities; 1,25D/25D 8/04:64/11 1/05:22/6 9/05:1,25D=12 10/06:22/8, 4/07:25/<4 chewed Ben. 40mg q8h; Mod. P2: 2/23/05, P2: 4/06; P3: 1/1/07
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Dr Trevor Marshall
Research Team
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Posted: Sat Mar 15th, 2008 20:45 |
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The key parameter is VDR transcriptional functionality, and not the absolute level of 1,25-D. Obesity is caused by the inability of the VDR to properly transcribe the antimicrobial peptides (and proteins) of the immune system.
The Th1 microbiota ensures that VDR activation and 1,25-D levels are no longer necessarily interdependent. There are now other factors in play. See my Figure 1 of the BioEssay.
I would also want to see how the 1,25-D samples were handled. Were they frozen? Was the shelf-storage identical for all subjects in the cohort?
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inge
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| Joined: | Mon Sep 25th, 2006 |
| Location: | Oslo, Norway |
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Posted: Mon Mar 17th, 2008 11:05 |
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Yes, the level of sun exposure seems to be one likely explanation.
The blood samples were not handled correctly (I know this as I used to work at the clinic that provided the data). Both non-freezing and shelf storage could have made the results less trustworthy. But still, correlations were observed, so I is unlikely that analysis error can explain the correlations in this particular study.
Last edited on Mon Mar 17th, 2008 11:08 by inge
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CFS/ME 125D64 25D12(dec 07) Ph1De06 daily lite exp NoIR use Ph2Mar07 ModPh2 Jun07 abx brkOct 07 r//t KFTs freq abx chg to control kidney IP Apr 08 phase 2 abx
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Dr Trevor Marshall
Research Team
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Posted: Mon Mar 17th, 2008 11:14 |
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inge wrote: The blood samples were not handled correctly (I know this as I used to work at the clinic that provided the data). Both non-freezing and shelf storage could have made the results less trustworthy.
Inge, either the samples were handled correctly, or the data on 1,25-D is worthless. There is no way to confound the potential handling deficiencies out of the results. The 1,25-D data is "worthless," not "less trustworthy."
The data on 25-D shows the correlation I would expect.
When we started this study in 2002, we got a lot of folk very angry. They spent money on getting 1,25-D tests done, and we told them the data was incorrect, and they needed to have the tests done again. We couldn't compromize, whenever there was doubt.
These days we have the new rules at Quest, and life is a lot simpler. But we discarded a huge number of unreliable data-points during the first few years. That is the only option available when the data could possibly contain a component of random error. In this case, we have studies which are showing results which appear to be counter-intuitive. Why are we trying to make excuses for methodological error?
Here is an interesting article which points really well to macrophage-centric immune changes in obesity:
"New method finds networks of genes behind obesity"
http://www.reuters.com/article/healthNews/idUSN1645889420080316
Last edited on Mon Mar 17th, 2008 11:56 by Dr Trevor Marshall
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inge
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Posted: Mon Mar 17th, 2008 12:22 |
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The question still remains: why was there a correlation? If the results were worthless there would be no correlation at all. How could measurement error lead to a higher 1,25 D for those with a low BMI, but not for those with a higher BMI?
Let's say the improper handling of the blood samples made the standard deviation increase from 5% to 10 % ( I have no idea of the actual figures). That would add noise to the results but not make the results worthless. I don't see what you mean.
Last edited on Mon Mar 17th, 2008 16:33 by inge
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CFS/ME 125D64 25D12(dec 07) Ph1De06 daily lite exp NoIR use Ph2Mar07 ModPh2 Jun07 abx brkOct 07 r//t KFTs freq abx chg to control kidney IP Apr 08 phase 2 abx
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Claudia
Member in Phase 3
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Posted: Mon Mar 17th, 2008 16:28 |
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Inge,
Perhaps the fact that the cohort in those tests were both fat and healthy could be the clue? (Read carefully!) It is pretty hard to collect a cohort of obese people who are actually "healthy" so the set has been sorted in favour of unusually healthy individuals.
If you think about the way - unfortunately - people become obese and get sick, is that they get fatter as they age and it all catches up with them eventually.
Perhaps these people are acquiring 25D in their over-generous diets and storing it in the fat they are accumulating, but the CWD bacteria in their bodies have not got to critical mass yet; not yet completely dysregulating the system, (hence clinical symptoms of inflammatory illness other than obesity) where 1,25D would start being pumped massivly into the system. Add to that the propensity for inaccurate test results, and you get these poorly drawn conclusions.
Just me being theoretical...
Claudia
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MP Phase1 23Mar_06; Phase2 July 10_06; Phase3 Nov 4_06. Dx Thyroiditis (Thyroxine); arthritis; glaucoma; CFS (1988-92);Kidney & bladder probs. Feb06 1,25D=43.3; Aug07 1,25D=27.5; Feb06 25D=44; Aug07 25D=28; Nov07 25D=36; Mar08 25D=16.4
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Knochen
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| Joined: | Thu Feb 23rd, 2006 |
| Location: | USA |
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Posted: Mon Mar 17th, 2008 17:08 |
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Here's an interesting article from today's news.
http://tinyurl.com/2paawx
New method finds networks of genes behind obesity
Naturally, they blame the diet for the problems, even as the point out that the immune system and macrophages in particular are involved! Close, but no cigar. The evidence is right there in front of them, but they persist in the old models.
Ye gods... You'll pardon me while I have a look at some bird entrails and light some incense. I wouldn't want to be thought of as being behind the times! 
Last edited on Mon Mar 17th, 2008 17:09 by Knochen
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Reiter's Syndrome 25+ yrs, fatigue, joints, muscles, migraine, brainfog| 25D 6 ng/ml |Benicar May06|Ph1 June06|Ph 2 Sept06|Ph 3 Jan 07|NoIRs K-Cream Zinc Oxide cream - Always covered!
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Dr Trevor Marshall
Research Team
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Posted: Mon Mar 17th, 2008 17:29 |
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Inge,
Although the concepts of random error would seem appropriate, they often are not. For example, we examined one study where the samples were put on a shelf until enough were collected to make it worthwile to run the radioimmunoassay. This was usually done at the end of each study cycle, and thus a bias was introduced, based on the order in which the patients were seen, rather than upon a random selection. Without having complete details of the exact study methodology it is usually not possible to deduce the nature of any methodological errors.
The Canadian study on Vitamin D, on which I wrote a critical letter, did not freeze, or even bother to calibrate their assay, just relying upon the average value measured on their lab staff as being a "population average." There is a lot of sloppy thinking in rsearch these days 
http://www.cmaj.ca/cgi/content/full/167/8/849
Last edited on Mon Mar 17th, 2008 17:51 by Dr Trevor Marshall
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Markt9452
Member in Phase 2
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Posted: Mon Mar 17th, 2008 17:51 |
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The premise that BMI Body Mass Index is an accurate measure of obesity is not correct.
BMI categories do not take into account many factors such as frame size and muscularity. The categories also fail to account for varying proportions of fat, bone, cartilage and water weight.
A professional athlete may score overweight or obese due to the fact that muscle is denser than fat.
The BMI makes simplistic assumptions about distribution of muscle and bone mass.
Invented around 1830, the BMI is simply a persons body weight divided by the square of their height. It is not a measurement of total body fat percentage or an accurate measure of obesity.
This study has nothing to do with obesity.
Many errors, of a truth, consist merely in the application of the wrong names of things.
- Spinoza
Last edited on Mon Mar 17th, 2008 17:53 by Markt9452
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Th1 Inflammation Lyme vertigo fatigue brain fog skin lesions tinnitis 125D20 D2510 Ph1Feb08 Ph2Apr08 daily lite exp covered up NoIRs
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Lottis
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| Location: | Akureyri, Iceland |
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Posted: Sat May 10th, 2008 12:43 |
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Hej Inge! 
Have you come any further into this subject, that you want to share with me. I have an extra interest in this, since it is becoming a serious problem here in Iceland, the obesity in all ages.
- One thing that enters my mind is that the CYP 3A1 is regulated from both liver and intestines.
- We also know that the gut flora among many of the obesite people differs from a lean flora.
- Also, like Claudia wrote, the fat is stored in the body and starts to be used in the metabolism after about 30 minutes of low level activity, especially on a fasting stomach.
Anyway, let me know how you are thinking! /Lottis
Last edited on Sat May 10th, 2008 16:20 by Lottis
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HTN,LVH,CHF,arrhythmia,hypercholesterol,IBS? fibromyalgia? achne rosasea e.c.t.|15feb-07 init. 1,25D 37,5,|25-D 7,8(latest 15/2-07)| Ph1 29/5-08|Med;verapamil|carvedilol|Furix|Stesolid|Cymbalta|Magnyl|NoIR's|covered up|disabled|
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inge
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Posted: Sat May 10th, 2008 15:53 |
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Hei Lottis!
I am afraid I don't have anything to say that would elucidate the cause for the observed relationship between obesity and 1,25-D.
As for Markts comment: BMI is a good indicator of obesity in studies like this one. Sure, BMI can be highly misleading for a single subject, but when it comes to doing correlation calculations for a large cohort like this one it is a completely different story. Furthermore, very few of the subjects in this cohort did heavy resistance exercise/had a large muscle mass.
Inge
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CFS/ME 125D64 25D12(dec 07) Ph1De06 daily lite exp NoIR use Ph2Mar07 ModPh2 Jun07 abx brkOct 07 r//t KFTs freq abx chg to control kidney IP Apr 08 phase 2 abx
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Markt9452
Member in Phase 2
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Posted: Mon Jul 7th, 2008 02:12 |
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Waist Circumference and Mortality
http://aje.oxfordjournals.org/cgi/content/abstract/167/12/1465
Last edited on Mon Jul 7th, 2008 02:15 by Markt9452
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Th1 Inflammation Lyme vertigo fatigue brain fog skin lesions tinnitis 125D20 D2510 Ph1Feb08 Ph2Apr08 daily lite exp covered up NoIRs
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NickBowler
Member in Phase 3
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Posted: Fri Jul 11th, 2008 10:53 |
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Here are some articles which shed some light on external factors such as diet that can compromise the working of genes by affecting the processes of methylation and histone deacetylation, which then compromise the functionality of the VDR and give rise to amongst other things, a propensity to obesity:
http://www.newscientist.com/channel/life/mg19926641.500-rewriting-darwin-the-new-nongenetic-inheritance.html
http://cat.inist.fr/?aModele=afficheN&cpsidt=18043334
http://www.pnas.org/content/105/24/8250.abstract
http://www.ncbi.nlm.nih.gov/pubmed/10877839
If foods can have such powerful effects, for sure active interference from bacteria certainly can, no doubt they are producing interference RNA too.
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Sarcoirodis CIDP, MP start 11/07, NoIRs, 02/08 25D-8, Ph3 since 07/08|
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