Low vitamin D level predicts cognitive decline in older population

September 14, 2015, Rutgers University

Older adults with deficiencies in vitamin D experience more rapid cognitive decline over time than those with adequate vitamin D levels.

In a study published Sept. 15 in the Journal of the American Medical Association-Neurology, Joshua Miller, professor of nutritional sciences at the Rutgers School of Environmental and Biological Sciences, found that people with low levels of vitamin D experienced rates of cognitive decline at a much faster pace than people with adequate vitamin D status.

"There were some people in the study who had low vitamin D who didn't decline at all and some people with adequate vitamin D who declined quickly," said Miller. "But on average, people with low vitamin D declined two to three times as fast as those with adequate vitamin D."

Vitamin D - known for its importance for bone health—is obtained primarily through sun exposure and some foods. Researchers have also found that vitamin D has a major impact on how the body, including the brain, functions.

Miller's study—conducted with Charles DeCarli, Danielle Harvey and others at the Alzheimer's Disease Center at the University of California-Davis—was conducted between 2002 and 2010. The 382 people involved were assessed for vitamin D levels and cognition once a year for an average of five years. They ranged in age from their 60s to their 90s, with the largest group in their 70s.

The study included people with normal cognition, mild cognitive loss, and dementia. Unlike previous studies of vitamin D and dementia, this group was racially and ethnically diverse, including whites, African Americans and Hispanics. Most (61 percent) had low vitamin D levels in their blood; 54 percent of the whites and 70 percent of the African-Americans and Hispanics had low blood levels of vitamin D.

While individuals with darker skin are more likely to have low levels of vitamin D because melanin, the pigment that makes skin dark, blocks the ultra-violet rays that help the skin synthesize vitamin D, the researchers found no difference in the rates of cognitive decline based solely on racial or ethnic lines. In other words, low vitamin D was associated with faster cognitive decline regardless of race or ethnicity.

Although taking too much vitamin D can be dangerous, Miller said these findings suggest that people over 60 should consult their physician about taking vitamin D supplements.

"Some people may have had melanoma or fear getting it," Miller said. "Or, they may live in climates where the sun isn't powerful enough, or do work that keeps them out of the sun. That's where supplements come in."

Meanwhile, he said, more research needs to be done including performing randomized controlled clinical trials.

"This will give us the additional information that we need to help determine whether vitamin D supplements can be used to slow the rate of and prevent dementia in ," Miller said.

Explore further: Low levels of vitamin D are associated with mortality in older adults

More information: JAMA Neurol. Published online September 8, 2015. DOI: 10.1001/jamaneurol.2015.2115

Related Stories

Low levels of vitamin D are associated with mortality in older adults

October 2, 2012
Low levels of vitamin D and high levels of parathyroid hormone are associated with increased mortality in African American and Caucasian older adults, according to a new study accepted for publication in The Endocrine Society's ...

Vitamin A implicated in the development of alcoholic liver disease

September 1, 2015
With a name like "Alcoholic Liver Disease," you may not think about vitamin A as being part of the problem. That's exactly what scientists have shown, however, in a new research report appearing in the September 2015 issue ...

Benefits of vitamin B12 supplements for older people questioned

July 1, 2015
Vitamin B12 supplements offer no benefits for neurological or cognitive function in older people with moderate vitamin B12 deficiency, according to a new study published in the American Journal of Clinical Nutrition.

Vitamin D supplements may improve kidney transplant recipients' health

November 8, 2013
Adequate vitamin D levels are important for maintaining kidney transplant recipients' health, according to a study that will be presented at ASN Kidney Week 2013 November 5-10 at the Georgia World Congress Center in Atlanta, ...

Study examines vitamin D deficiency and cognition relationship

April 15, 2014
Vitamin D deficiency and cognitive impairment are common in older adults, but there isn't a lot of conclusive research into whether there's a relationship between the two.

Low vitamin D causes brain damage

December 2, 2013
A new study led by University of Kentucky researchers suggests that a diet low in vitamin D causes damage to the brain.

Recommended for you

Americans are getting more sleep

January 19, 2018
Although more than one in three Americans still don't get enough sleep, a new analysis shows first signs of success in the fight for more shut eye. According to data from 181,335 respondents aged 15 and older who participated ...

Wine is good for you—to a point

January 18, 2018
The Mediterranean diet has become synonymous with healthy eating, but there's one thing in it that stands out: It's cool to drink wine.

Sleep better, lose weight?

January 17, 2018
(HealthDay)—Sleeplessness could cost you when it's time to stand on your bathroom scale, a new British study suggests.

Who uses phone apps to track sleep habits? Mostly the healthy and wealthy in US

January 16, 2018
The profile of most Americans who use popular mobile phone apps that track sleep habits is that they are relatively affluent, claim to eat well, and say they are in good health, even if some of them tend to smoke.

Improvements in mortality rates are slowed by rise in obesity in the United States

January 15, 2018
With countless medical advances and efforts to curb smoking, one might expect that life expectancy in the United States would improve. Yet according to recent studies, there's been a reduction in the rate of improvement in ...

Can muesli help against arthritis?

January 15, 2018
It is well known that healthy eating increases a general sense of wellbeing. Researchers at Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU) have now discovered that a fibre-rich diet can have a positive influence ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.