April 25, 2007
Low Vitamin D Speeds Muscle Decline In Old Age?

Low levels of vitamin D might accelerate aging.

For the current study, researchers analyzed data from the InCHIANTI study, which evaluated factors contributing to the decline of mobility in late life. The study involved 976 people who were 65 years and older from two towns in the Chianti area of Italy. The mean age of participants was 74.8 years. Data were collected from Sept. 1998 through March 2000.

Participants completed a short physical performance test of their walking speed, ability to stand from a chair and ability to maintain their balance in progressively more challenging positions. In addition, handgrip strength, a predictor of future disability, was measured using a hand-held dynamometer.

The researchers found that physical performance and grip strength were about five to 10 percent lower in those who had low levels of vitamin D. After looking at other variables that could influence the results, such as body mass index, physical activity, the season of the year, mental abilities, health conditions and anemia, the results held true.

The study wasn’t designed to evaluate whether low vitamin D levels actually cause poor physical performance, but the results suggest the need for additional research in this area, said Houston. She said vitamin D plays an important role in muscle function, so it is plausible that low levels of the vitamin could result in lower muscle strength and physical performance.

“But it’s also possible that those with poor physical performance had less exposure to sunlight resulting in low vitamin D levels,” she said.

Current recommended daily intake for vitamin D might be too low.

Current recommendations call for people from age 50 to 69 to get 400 international units (IUs) of vitamin D per day and for those over age 70 to get 600 IUs. Many researchers, however, suggest that higher amounts may be needed.

“Higher amounts of vitamin D may be needed for the preservation of muscle strength and physical function as well as other conditions such as cancer prevention,” said Houston. “The current recommendations are based primarily on vitamin D’s effects on bone health.”

We spend less time outside than our ancestors did. It seems likely we do not make enough vitamin D from sun exposure. At the same time, many of us do not get much vitamin D from foods. So vitamin D deficiency might be common.

Share |      Randall Parker, 2007 April 25 10:59 PM  Aging Diet Studies


Comments
Ted said at April 26, 2007 12:34 AM:

I want to know how many of those with low levels of vitamin D ate bacon more than 14 times a month!

Joshthenutritionist said at April 26, 2007 1:45 AM:

Funny, I just did a presenation on Vitamin D and Cancer, vitamin D def. is prevelant amoung all races in the US, highest about Black americans with numbers at 43%. In terms of cancer prevention, you serum 25(OH) D levels to be at 30 ng/mL or greater, up to 150 ng/mL this can be achieved by 1000 IU a day safely without fear of toxic effects and at the cost of 3 cents per day. do a pubmed search loads of evidence in support, shame its not being put to action

Jake said at April 26, 2007 9:40 AM:

Another shame is that Doctors are not checking for Vitamin D with the normal blood tests that come with your annual physical. Since people over 60 lose some ability to convert sunlight into Vitamin D, a D test should be a mandatory Medicare test.

Nick said at April 27, 2007 9:02 AM:

This, together with cancer prevention benefits, certainly seems to suggest that the risks of D deficiency are much, much greater than the risks of skin cancer.

Randall Parker said at April 27, 2007 9:03 PM:

Nick,

Plus the increased risk of auto-immune diseases that comes with vitamin D deficiency.

Nick said at April 28, 2007 8:27 AM:

Randall,

Yes, we give D to our German Shepherd, to help treat her Degenerative Myelopathy, a dog version of MS. She gets 400 units, we take 1,000/day.

Lou Pagnucco said at May 2, 2007 9:22 AM:

However, this item just appeared on Reuters:

"High calcium and vitamin D intake may have a down side"
http://www.reuters.com/article/healthNews/idUSTON18120620070501

Some key excerpts:
"In one of the first studies to examine the relationship between diet and brain lesions, researchers observed that elderly people who reported higher calcium and vitamin D intake were much more likely to have greater volumes of brain lesions -- regions of damage that can increase risk of cognitive impairment."

"...we hypothesize that our findings may be due to vascular calcification, whereby calcium is taken up into the blood vessel walls."

"We are concerned that some of this extra calcium may end up in the blood vessel walls rather than the bone. This may be a particular problem for individuals with renal disease since calcium excretion may be impaired"

Possibly, vitamin K would prevent this vascular calcification.
For example, see -
"Vitamin K and vascular calcification" at PubMed
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=15775408&dopt=Abstract

Post a comment
Comments:
Name (not anon or anonymous):
Email Address:
URL:
Remember info?

                       
Go Read More Posts On FuturePundit
Site Traffic Info
The contents of this site are copyright ©