Vitamin D deficiency linked to Parkinson's disease, cognitive decline

[one...two...tree 2,762]

(This is very interesting as my father, who was diagnosed with Parkinson's over a year ago, recently discovered from his doctor that his vitamin D levels are way below normal.)

By Nicholette Zeliadt

Studies of vitamin D have been on the rise in recent years, and with good reason—a 2009 estimate suggests that nearly three quarters of teens and adults in the U.S. are deficient in this vital nutrient. Vitamin D deficiency not only causes rickets, a skeletal disorder in which the bones are soft and weak, but has also been associated with a rapidly increasing range of chronic conditions like cancer, heart disease, and type 2 diabetes. Now, two new studies suggest a link between vitamin D and neurological disorder: Older people with insufficient vitamin D levels may be more likely to develop Parkinson's disease and experience cognitive decline. The first, led by Paul Knekt and colleagues at the National Institute for Health and Welfare, Finland, examined levels of vitamin D in the blood of 3,173 Finnish men and women aged 50 to 79 determined to be free of Parkinson's disease at the start of the study. The researchers then examined the incidence of Parkinson's disease in these participants over a 29-year follow-up period. They found that participants with the highest levels of vitamin D (more than 50 nmol/L) had a 65 percent lower risk of developing Parkinson's disease than those with the lowest vitamin D levels (less than 25 nmol/L). The researchers accounted for potentially confounding variables such as age, sex, marital status, education, alcohol consumption, smoking, physical activity and month of blood draw.

Parkinson's disease is a progressive neurodegenerative disorder that leads to impaired movement and speech, and is thought to result from insufficient dopamine levels in the brain. How vitamin D may protect against Parkinson's is not understood, although there is limited evidence from cell-based and animal models that vitamin D may prevent the loss of dopaminergic neurons (cells that produce dopamine).

One important limitation to the study is that the average vitamin D concentration of all the study participants (approximately 40 nmol/L) falls well below what is considered to be optimal (more than 75 nmol/L). Therefore, whether supplementation with vitamin D would further lower the risk for Parkinson's remains unknown. Nevertheless, the study suggests that not having enough vitamin D may predispose individuals to Parkinson's, and provides a starting point for further investigation. The results were published online July 12 in the Archives of Neurology.

In the second study, David Llewellyn of the University of Exeter and colleagues examined vitamin D levels among 858 Italian men and women age 65 and older. They found that more than half of the participants with dementia were vitamin D deficient (less than 50 nmol/L). What's more, cognitive tests revealed that severely deficient individuals (less than 25 nmol/L) were 60 percent more likely to undergo cognitive decline over the six-year follow-up period. This study appears online July 12 in the Archives of Internal Medicine.

Humans can obtain vitamin D by eating oily fish or fortified foods, and it is also photosynthesized in the skin upon exposure to adequate amounts of ultraviolet B (UVB) rays in sunlight. Major factors that influence vitamin D status in humans include season, latitude, age, skin tone, diet and supplement use. The U.S. Institute of Medicine currently recommends that adult men and women aim for a daily intake of 200 to 600 International Units (IU) of vitamin D.

New guidelines for vitamin D intake were published online July 12 in the Canadian Medical Association Journal by scientists from Osteoporosis Canada, a nonprofit organization. Because vitamin D influences calcium absorption and may protect against osteoporosis, the authors advise an increased daily intake of 400 to 1000 IU for healthy Canadians under age 50, and up to 2000 IU for those older than 50. The researchers state the changes are necessary because winter sunlight north of the 35th parallel (which coincides with the southern border of Tennessee) provides insufficient UVB for people living in that region to adequately make vitamin D.

The studies by Knekt and Llewellyn are not the first to link vitamin D deficiency with neurological problems, however. A role for vitamin D has previously been suggested in multiple sclerosis, autism and schizophrenia.

Some experts advise interpreting the results of these and other observational studies of vitamin D with caution. The above studies relied on participants from specific geographic areas, so more study is needed to determine whether the findings apply to other regions. Furthermore, "low vitamin D levels may simply be a marker for lower health status rather than a cause of it," Andrew Grey, professor of medicine at the University of Auckland, wrote in an editorial in the Archives of Internal Medicine. This is because vitamin D levels are directly related to sunlight exposure and physical activity; less healthy individuals are therefore likely to be less active and more sunlight-deprived, and have lower levels of vitamin D.

"It is now time to test the various hypotheses generated by observational studies of vitamin D…in adequately designed and conducted randomized controlled trials," Grey concluded. "We should invest in trials that provide the best possible evidence on the benefits and risks of vitamin D before we invest in costly, difficult, and potentially unrewarding interventional strategies."

http://www.scientifi...park-2010-07-12

[TBoneTX 45,465]

Parkinson's is a disease from the Devil himself. May your dad abide it with the attitude of "I may have Parkinson's, but Parkinson's doesn't have ME." Let's all pray for a cure.

[KaiserD 12]

So... being deficient in vitamin D and having had a family member with PD probably isn't a good thing is it

[Kathryn41 3,205]

It is surprisingly easy to be vitamin D deficient as I have found out. Vitamin D is required by Calcium and Magnesium to help counter osteoporosis, so even though I get good exposure to the sun daily and eat a healthy diet, I supplemented my diet with 400 IU. After a bone density scan revealed osteopenia (pre-osteoporosis), my endocrinologist increased my vitamin D supplementation to 1000 IU. My last vitamin D test showed a reading of 33 - still low - so my supplementation has now been increased to 2000 IU. I live in Georgia now, not Canada, and I do get more sun exposure every day but I still had low vitamin D levels, so I can appreciate how much more difficult it is to get proper vitamin D levels further north.

The body is a nicely balanced mechanism and you just need to have one thing stop working right to realize just how finely tuned that balance is. Our modern diet and life-styles do indeed stress that balance in many ways we are only now realizing. I have no trouble accepting that a vitamin deficiency - in this case vitamin D - can trigger or predict the development of a certain disorder such as Parkinson's Disease.

Edited July 16, 2010 by Kathryn41

[Kathryn41 3,205]

3 racist comments have been removed

Edited July 16, 2010 by Kathryn41

[HAL 9000 96]

Its more of an Alzheimer's cognition find, but snorted insulin (via the nose) is being recently purported to improve cognitive scores in patients displaying signs of AD.

PD and AD share some hallmark pathology.

[HAL 9000 96]

It is surprisingly easy to be vitamin D deficient as I have found out. Vitamin D is required by Calcium and Magnesium to help counter osteoporosis, so even though I get good exposure to the sun daily and eat a healthy diet, I supplemented my diet with 400 IU. After a bone density scan revealed osteopenia (pre-osteoporosis), my endocrinologist increased my vitamin D supplementation to 1000 IU. My last vitamin D test showed a reading of 33 - still low - so my supplementation has now been increased to 2000 IU. I live in Georgia now, not Canada, and I do get more sun exposure every day but I still had low vitamin D levels, so I can appreciate how much more difficult it is to get proper vitamin D levels further north.

The body is a nicely balanced mechanism and you just need to have one thing stop working right to realize just how finely tuned that balance is. Our modern diet and life-styles do indeed stress that balance in many ways we are only now realizing. I have no trouble accepting that a vitamin deficiency - in this case vitamin D - can trigger or predict the development of a certain disorder such as Parkinson's Disease.

My suspicion is that if Vitamin D has a significant effect in being neuroprotective, its likely helping stabilize Calcium flux intracellularly. Calcium is very tightly regulated in healthy cells as its used in all kinds of biochemistry. I wouldn't be surprised if vitamin D shows up in future studies as a cofactor for many of the several enzymes involved in pumping Calcium out of the endoplasmic reticulum or putting it back in. Or involved in signaling transduction cascades targeted at metabolizing other nutrients. mTOR is a popular pathway being explored currently in the endocrinology field, and Calcium fits prominently in its signal cascade.

[one...two...tree 2,762]

Welcome back, HAL! Glad to see you see here again!

[Kathryn41 3,205]

My suspicion is that if Vitamin D has a significant effect in being neuroprotective, its likely helping stabilize Calcium flux intracellularly. Calcium is very tightly regulated in healthy cells as its used in all kinds of biochemistry. I wouldn't be surprised if vitamin D shows up in future studies as a cofactor for many of the several enzymes involved in pumping Calcium out of the endoplasmic reticulum or putting it back in. Or involved in signaling transduction cascades targeted at metabolizing other nutrients. mTOR is a popular pathway being explored currently in the endocrinology field, and Calcium fits prominently in its signal cascade.

That actually makes a lot of sense, and I wouldn't be surprised to hear that result as well.

I have personally become very aware of the synergy between calcium, vitamin D and magnesium metabolism. About a month ago I was having unexplained and severe leg cramps, even with the additional supplementation. Increasing potassium didn't make a difference but after a test that determined my body wasn't utilizing the type of supplemental calcium I was using very well, (calcium carbonate), the doctor suggested switching the type of calcium I was using to Calcium citrate. I haven't had a re-test for the levels but I do know that within 3 days of changing to the different type of calcium, the leg cramps stopped and have not returned, showing that for me the bio-availability of the calcium carbonate was not as good as the calcium citrate. The lower availability of vitamin D which has also since been increased may have been a contributing factor. I have also noticed that since then my sleep is a lot deeper and more restful - which is one of the reasons why I added supplemental magnesium as poor sleep is supposed to be an indicator of low magnesium levels and calcium requires the proper ratio of magnesium to be effectively utilized. So, it s very much a synergy of those 3 in this instance.

As I mentioned before, the body is a nicely balanced machine that if one thing gets out of whack it causes a host of other problems. (My main 'out of whack' is that my pancreas Beta cells don't produce insulin which contributes to a host of other nutritional imbalances in addition to glucose- hence the big concern about appropriate nutritional supplementation).

Edited July 17, 2010 by Kathryn41

[HAL 9000 96]

Type 1, Kathryn?

I probably wouldn't go as far as stating an actual 'synergistic effect' but I can guarantee that any deficiency (or even excess thereof) would alter steps in multiple biochemical cascades that might or might not 'crosstalk' with each other. Mineral balance at times (such as with potassium and sodium) is a crucial aspect of cellular ion pumps and channels that exchange these ions, and one cascade of enzymatic reactions might require different ions at different locations within the cell to effect their activities properly.

Welcome back, HAL! Glad to see you see here again!

Not going to get too used to it either, unfortunately... I am staring down the publication pipeline and it needs more of me in it!

[Kathryn41 3,205]

Yep, type 1. Since late 1992.