The truth is that overexposure to the sun can cause problems. What you probably don’t know – underexposure can be dangerous to your health. Here’s why: A new study looking at the relationship between vitamin D serum levels and the risk of colon and breast cancer across the globe has estimated the number of cases of cancer that could be prevented each year if vitamin D3 levels met the target proposed by researchers.
Cedric F. Garland, a cancer prevention specialist at the Moores Cancer Center at the University of California, San Diego (UCSD) estimated that 250,000 cases of colorectal cancer and 350,000 cases of breast cancer could be prevented worldwide by increasing intake of vitamin D. In particular, they were referring to vitamin D3. This is particular in countries north of the equator. Vitamin D3 is available through diet, supplements and exposure of the skin to direct sunlight.
The paper, which looks at the dose-response relationship between vitamin D and cancer, will be published in the August edition of the journal Nutrition Reviews. It stated that for the first time, we are saying that 600,000 cases of breast and colorectal cancer could be prevented each year worldwide, including nearly 150,000 in the United States alone,” said study co-author Garland.
This research study combined data from surveys of serum vitamin D levels during winter from 15 different countries. It is the first of such a study to look at satellite measurements of sunshine and cloud cover in countries where actual blood serum levels of vitamin D3 had also been measured. The figure was then applied to over 170 countries to estimate the average serum level of a vitamin D metabolite of people living there. Findings were compared to other findings.
The research data revealed a conflicting association of serum vitamin D with danger of colorectal and breast cancer. The protective effect began at levels ranging from 24 to 32 nanograms per milliliter of 25-hydroxyvitamin D concentration in the serum. The 25-hydroxyvitamin D level is the major indicator of vitamin D level status. The late winter average 25-hydroxyvitamin D in the U.S. is about 15-18 ng/ml. The researchers uphold that increasing vitamin D levels in populations, chiefly those in northern climates, has the probability to both prevent and possibly serve as an adjunct to existing treatments for cancer. These research studies had some very important findings for any reader to consider.
“This could be best achieved with a combination of diet, supplements and short intervals – 10 or 15 minutes a day – in the sun,” said Garland. It could be less for very fair-skinned individuals. He went on to say that “the appropriate dose of vitamin D in order to reach this level could be very little in a lifeguard in Southern California… or quite a lot for someone in Northern Europe who tends to remain indoors most of the year.”
The serum level recommended by the study would correspond to intake of 2000 International Units per day of vitamin D3 for a meaningful reduction in colorectal cancer. The researchers recommend 2000 IU/day, plus, when weather allows, a few minutes in the sun with at least 40% of the skin exposed, for a meaningful reduction in breast cancer incidence, unless the individual has a history of skin cancer or a photosensitivity disease. Garland also recommends moderate sun exposure and use of clothing and a hat when in the sun longer than 15 minutes.