Why should you keep your vitamin D level around 50 ng/ml? Four different sources, using four different rationales, and four different lines of reasoning, all lead to the same conclusion.
First, what is the vitamin D level of our closest simian relatives, such as chimpanzees living wild in Africa? Professor Reinhold Vieth reports the answer is between 40 and 60 ng/ml. This, by itself, does not prove we need such levels, but it certainly raises that question.
Second, what is the vitamin D level of humans who work in the sun without clothes, such as lifeguards, and without supplementing? We lived in the sun for 2 million years, so certainly lifeguards have more natural vitamin D levels than do people who work indoors. Again, the answer is between 40-60 ng/ml. Here, we have stronger naturalistic evidence unless one assumes the vitamin D levels of indoor workers are natural.
Third, what vitamin D levels do women have to achieve to convert from having little to having lots of vitamin D in their breast milk? Professors Bruce Hollis and Carole Wagner recently answered that question, again 40-60 ng/ml, enough to sustain the infant’s vitamin D levels. One could claim breast milk is not supposed to have vitamin D in it, and that primitive man was supposed to expose newborns to sunlight. But then you would be arguing that primitive man was supposed to expose their infants to predators, which I find unlikely. Besides, we know from the second reason that any woman receiving consistent full body sun exposure would have vitamin D in her breast milk.
Finally, what is the vitamin D level of people who show no evidence of substrate starvation? That is, at what level do people begin to store the parent compound (cholecalciferol) in their fat and muscles? Professor Robert Heaney answered that question: around 40 ng/ml. I remember seeing several patients in the hospital who had vitamin D levels of 40-50 ng/ml in February. Both had worked as roofers the summer before and both had worked with their shirts off. The mechanism for humans who migrated away from the equator must have been the same, to store the parent compound in muscle and fat during the summer for use in the winter. The body stores it well before it turns on the enzymatic machinery to get rid of excess vitamin D.
So we have the above four questions, questions from four very different sources. Chimps, outdoor workers, lactating women, and clinical subjects all lead to the same answer: 40 ng/ml is the lower limit of a natural level. Taking into account errors in laboratory testing and variations in human techniques, we must accept what the Endocrine Society recently recommended, that healthy vitamin D levels are somewhere around 50 ng/ml, levels the Vitamin D Council has advocated for the last 8 years.
From the Vitamin D Council Newsletter 19 September 2011
Tags: Viatmin D
The MedWatch August 2011 Safety Labeling Changes posting includes 44 products with safety labeling changes to the following sections: BOXED WARNINGS, CONTRAINDICATIONS, WARNINGS, PRECAUTIONS, ADVERSE REACTIONS, PATIENT PACKAGE INSERT, and MEDICATION GUIDE.
The “Summary Page” provides a listing of drug names and safety labeling sections revised:
http://www.fda.gov/Safety/MedWatch/SafetyInformation/ucm268289.htm
Clicking on a drug product name in the Summary View via the link above will take you to the “detailed view” page, which identifies safety labeling sections and subsections revised, along with a brief summary of new or modified safety information.
The following drugs had modifications to the BOXED WARNINGS, CONTRAINDICATIONS and WARNINGS sections:
- Accolate (zafirlukast) tablets
- Actos (pioglitazone hydrochloride) Tablets
- Bentyl (dicyclomine hydrochloride, USP) Capsules/Tablets, Oral Syrup and Injection
- Betapace and Betapace AF (sotalol HCl) Tablets
- BiCNU (carmustine for injection)
- Celexa (citalopram hydrobromide) Tablets and Oral Solution
- DepoCyt (cytarabine liposome injection)
- Ditropan (Oxybutynin chloride) Tablets
- Dostinex (cabergoline) Tablets
- Exjade (deferasirox) Tablets for Oral Suspension
- Haldol (haloperidol) Injection and Haldol Decanoate (haloperidol) IM Injection
- Hyzaar (losartan/hydrochlorothiazide) Tablets
- Kerledex (betaxolol hydrochloride/chlorthalidone) Tablets
- Kerlone (betaxolol hydrochloride) Tablets
- Lamictal (lamotrigine) Tablets, Chewable Dispersible Tablets, Lamictal Orally Disintegrating Tablets, and Lamictal XR Extended-Release Tablets
- Mobic (meloxicam) Tablets and Oral Suspension
- Multaq (dronedarone hydrochloride) Tablets
- Neurontin (gabapentin) Capsules, Tablets, and Oral Solution
- Platinol (cisplatin for injection, USP)
- Prinzide (lisinopril/hydrochlorothiazide) Tablets
- Reclast (zoledronic acid) Injection
- Saphris (asenapine) Sublingual Tablets
- Sensipar (cinacalcet) Tablets
- Tenoretic (atenolol/chlorthalidone) Tablets
- Tenormin (atenolol) Tablets
- Tenoretic (atenolol/chlorthalidone) Tablets
- Thallous Chloride [Tl-201] Injection
- Zoloft (sertraline hydrochloride) Tablets and Oral Concentrate
An excerpt from the Vitamin D Council Newsletter by Dr. John Cannell
Most of us, including myself, have a primitive understanding of genetics. Genes are the things you inherit and pass down to your kids. Defects in those genes cause incurable diseases, if they don’t kill you outright. The defects, or mutations, are acquired over generations of genes being exposed to mutagens, like x-rays, toxins, etc. and are passed down the line. Right? In what may be a seminal paper (actually an editorial) in Nature, Dr. John Timmersays: hold on, not so fast.
It appears that many of those mutations occur during the lifetime of the person in question. That is, you may well have a genetic disease that you did not inherit.
Timmer, J. Schizophrenia: genes matter (even though inheritance might not). Nature Genetics. 2011.
That explains the genetics of autism very nicely, but I wish Dr. Timmer had taken the next step, the incurable step. The genetic defects he is talking about are often quite minor in comparison to what we have grown accustomed to think about, like an entire chromosome trisomy 21 in Down syndrome (Down’s syndrome in the U.K.). No set of genetic push-pull railroad repair cars are going to fix that one, it’s just too big.
However, a number of proteins exist whose entire purpose in life is to go along the genome, like a railroad car, detecting small genetic variations in one set of genes, and fix them, sometimes using the other set of genes as a template for normal. At least that’s how a forensic psychiatrist understands the process.
And guess who is in charge of these little locomotives? Guess who protects your genome from these genetic variations, guess who is “The Defender of the Genome”? You guessed it; it’s just another one of vitamin D’s repair and maintenance functions. I’m just putting this all together in my mind, as the stack of papers on my desk attests. I didn’t discover anything; dozens of scientists have been studying these genetic repair mechanisms for years, including vitamin D’s involvement. As I learn it, I will tell you about the scientists whose lifetime of work is about to become a little more public.
However, it now makes perfect sense to me how vitamin D can cure some genetic diseases, like autism. Once your body has enough vitamin D, all those little genetic repair train cars can chug happily along, fixing the multiple little genetic variations that are the most common genetic findings in autism. Yes, autism is a genetic disease, or rather; it is a disease of the genes.
Eapen V. Genetic basis of autism: is there a way forward? Curr Opin Psychiatry. 2011 May;24(3):226-36. Review.
The Vitamin D Council, a nonprofit educational corporation based in California, launches their “Vitamin D and Cancer” campaign today, presenting 20 detailed summaries of the evidence on the role of vitamin D in preventing cancer. Epidemiologist Dr. William Grant prepared the evidence-based summaries. He is the founder of the nonprofit organization, Sunlight, Nutrition and Health Research Center (SUNARC) and serves as the Science Director for the Vitamin D Council.
Some researchers believe the link between vitamin D sufficiency and a decreased risk in cancer is promising. A randomized controlled trial found a 77% reduction in all-cancer incidence when the study group supplemented with 1100 IU/day of vitamin D plus 1450 mg/day calcium. Says Dr. Grant, “Based on various studies of UVB, vitamin D and cancer to date, it appears that global cancer burden can be reduced by 15-25% if everyone had vitamin D blood levels above 40 ng/ml.”
The summaries can be found under the “Health conditions” tab on the Vitamin D Council website, or more specifically at http://www.vitamindcouncil.org/health-conditions/cancer/. The Vitamin D Council hopes the campaign will spread more awareness about the importance of vitamin D sufficiency and the dangers of vitamin D deficiency.
Top ten facts about vitamin D and cancer (presented in the summaries):
- Many studies have found solar ultraviolet-B (UVB) and vitamin D associated with reduced risk of breast, colon, and rectal cancer.
- A randomized controlled trial with 1100 IU/day vitamin D3 plus 1450 mg/day calcium found a 77% reduction in all-cancer incidence.
- Geographical studies have found reduced risk in mortality rates for 20 types of cancer in regions of higher solar UVB doses.
- Observational studies have found that the risk of breast, colon, and rectal cancer fall as vitamin D blood levels rise at least up to 40 ng/mL (100 nmol/L).
- Mechanisms have been proposed to explain how vitamin D acts to reduce the risk of cancer from starting, growing, and spreading.
- Those who develop nonmelanoma skin cancer may have produced enough vitamin D to reduce their risk of internal cancers.
- Those with higher vitamin D blood levels at time of cancer diagnosis had nearly twice the survival rate of those with the lowest levels.
- African-Americans have an increased risk of cancer in part due to lower vitamin D blood levels because of darker skin.
- Higher UVB exposure early in life has been found associated with reduced risk of breast and prostate cancer.
- Those diagnosed with breast, colon and prostate cancer in summer in Norway had higher survival rates than those diagnosed in winter.
Tags: anti-cancer, vitamin D