As my readers and patients know, I am very passionate about normalizing the vitamin D levels of the population of the world. It is now estimated that over 1 billion people worldwide are deficient in vitamin D.
More and more studies are coming out showing the benefit of vitamin D for a plethora of medical conditions.
Now I am very excited to announce to you that a new study in the prestigious journal Neurology, the official journal of the American Academy of Neurology, has just published a landmark article showing a strong association between vitamin D deficiency and Alzheimer’s disease.
This study was carried out by lead author David Llewellyn, PhD, and is thought by the authors of the article to be the first large and prospective study looking at the relationship between Alzheimer’s disease and vitamin D in patients.
The findings showed that for the elderly Americans who took part in the study, those who were severely deficient in vitamin D were 122% more likely to develop Alzheimer’s disease. Those who were just deficient had a 69% percent increase in the likelihood of developing Alzheimer’s disease.
These are astonishing numbers!
The study looked at over 1600 adults who were 65 years or older who were deemed to be free of other disease. After meauring their baseline vitamin D levels, the people in the study were followed for six years to see who went on to develop Alzheimer’s disease or some other form of dementia.
The lead author of the study, Dr.Llywelyn said “We expected to find an association between low vitamin D levels and the risk of dementia and Alzheimer’s disease, but the results were surprising – we actually found that the association was twice as strong as we anticipated.”
He went on to say that “We need to be cautious at this early stage and our latest results do not demonstrate that low vitamin D levels cause dementia. That said, our findings are very encouraging and even if a small number of people could benefit, this would have enormous public health implications given the devastating and costly nature of dementia.”
He recommended clinical trials to establish whether increasing in advance people’s vitamin D levels would delay orprevent the onset of Alzheimer’s disease and other dementia.
This study puts a lot of wind in the sails of physicians who study vitamin D, including myself. However, I want to point out to my readers what levels the researchers used to define deficiency!
They defined deficiency as a vitamin D level less than 20 ng/mL. They defined a severe deficiency as a vitamin D level less than 10 ng/mL.
In the eyes of progressive vitamin D researchers these are extraordinarily low vitamin D levels. But these are the levels where research is done.
In spite of the strong evidence that many extraskeletal benefits are derived from levels of vitamin D between 40 and 70 ng/mL, the very conservative Institute of Medicine of the United States, recommends a level of 20 ng/mL, and the Endocrine Society recommends a level of 30 ng/mL for good health. Even these two organizations cannot agree on a healthy vitamin D level.
I clearly do not agree with these recommendations for vitamin D blood levels , nor do my vitamin D research colleagues. My recommendation for a healthy person is to keep their vitamin D blood level between 40 and 70 ng/mL. The medical literature again for extra skeletal benefit strongly supports these numbers.
The Authors of the article, of course, call for additional prospective research. This will take many more years to accomplish.
My position on this is that there is no harm in normalizing our own levels of vitamin D until the research comes out. But articles like this one showed the handwriting on the wall that proper vitamin D levels can be protective against many health conditions.
Where do you stand on this issue of what level of vitamin D should we have? I look forward to your comments on twitter or Facebook.
Dr. Soram
Link between vitamin D, dementia risk confirmed
Vitamin D and cognition in older adults’: updated international recommendations
Vitamin D and the risk of dementia and Alzheimer disease
Metaanalysis of All Cause Mortality According to Serum 25Hydroxyvitamin D
Vitamin D Video by Dr Oz
Nice Video by Dr Oz. I don’t agree with his sun recommendations or his cod liver oil recommendations. I also don’t agree with his recommendation of only 1000 IU per day. I recommend 2000 a day for an otherwise healthy adult, but otherwise, this interview has some good education about Vitamin D including his talk about the Vitamin D winter for those in the northern 2/3 of the US. Don’t forget your kids too!
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