A study -- published in the European Journal of Clinical Nutrition -- reveals that adults with low vitamin D levels have a 30% greater risk of death than people who had higher levels.
Led by Ellen Smit of Oregon State University, USA, the randomised, nationally representative study found that overall, people who were frail had more than double the risk of death than those who were not frail. However, frail adults with low levels of vitamin D had triple the risk of mortality than those were not frail and who had higher levels of the sunshine vitamin.
Smit noted that whilst past studies have separately associated frailty and low vitamin D with a greater mortality risk, the new study is the first to look at the combined effect.
In general, those who had lower vitamin D levels were more likely to be frail, the researchers said. However, they noted that because of the cross-sectional nature of the survey they could not determine if low vitamin D contributed to frailty, or whether frail people became vitamin D deficient because of health problems.
Smit argued however, that longitudinal analysis on death showed it may not matter which came first.
"If you have both, it may not really matter which came first because you are worse off and at greater risk of dying than other older people who are frail and who don't have low vitamin D," she said.
The authors concluded that the results of their study suggest that low serum 25(OH)D is associated with frailty, adding that there are â€˜additive joint effects' of serum 25(OH)D and frailty on all-cause mortality in older adults.
Tobias Eckle, MD, PhD said that our circadian rhythm--the physical, mental and behavioral changes prompted by light and darkness that occur over each 24-hour period--helps determine the level of a certain protein that can minimize the cell damage and cell death caused by a heart attack. This protein might even stop a heart attack in its tracks. So Dr. Eckle and his colleagues were eager to see whether exposure to certain kinds of light at a certain time might be effective at boosting levels of this protein.
In the study, researchers divided mice into two groups. One group was exposed to light boxes emitting light that was the same level of brightness as daylight ("bright light"), and others were exposed to regular room lighting ("regular light"). Both groups were exposed to the light first thing in the morning at 6:00 am.
Then the mice were given anesthesia and heart attacks were triggered in them. Researchers found that mice that had been exposed to three hours of "bright light" had three times the amount of the protective protein as the mice that had been exposed to "regular light"--and, incredibly, the "bright light" mice's hearts had experienced only one-fifth as much damage!
Here are some safe ways from Dr. Eckle to shed more light on your daily routine...
1. Take a daily walk outdoors. Even 10 to 20 minutes a day is better than nothing.
2. Get sunlight while indoors. Sit near large, bright windows.
3. Use a light therapy box. If you can't follow either of the first two tips, or if you're at high risk for skin cancer and want to avoid UV rays at all costs, this may be the best option for you. Available online for about $50 and up, light therapy boxes mimic the brightness of sunlight.
John Summerly is nutritionist, herbologist, and homeopathic practitioner. He is a leader in the natural health community and consults athletes, executives and most of all parents of children on the benefits of complementary therapies for health and prevention.