A new study published in the Journal of Steroid Biochemistry and Molecular Biology, found that people living in regions with low sunlight may have a higher risk of pancreatic cancer. The research suggests this may be due to lack of vitamin D. 

"If you're living at a high latitude or in a place with a lot of heavy cloud cover, you can't make vitamin D most of the year, which results in a higher-than-normal risk of getting pancreatic cancer," said study co-author Dr. Cedric Garland, an adjunct professor with the University of California, San Diego School of Medicine's Department of Family Medicine and Public Health.

"People who live in sunny countries near the equator have only one-sixth of the age-adjusted incidence rate of pancreatic cancer as those who live far from it," Garland said in a university news release. "The importance of sunlight deficiency strongly suggests -- but does not prove -- that vitamin D deficiency may contribute to risk of pancreatic cancer."

Sources of Vitamin D

Foods like fatty fish (shellfish, tuna, salmon), egg yolks, cheese, beans, fortified products like milk, cereal and juices work great. But subjects seemed to need much more vitamin D that cannot be provided by food.  

That's where direct outdoor exposure to the sun comes in, since it boosts the body's production of vitamin D. A little more than 10 minutes in the sun will give the amount of vitamin D we need in one day. 

Garland and colleagues have previously linked higher vitamin D levels to lower levels of breast and colorectal cancer. Now, they're reporting a similar connection to pancreatic cancer.

The researchers reached their conclusions after reviewing information from more than 100 countries. They also adjusted their results so they wouldn't be thrown off by other risk factors, such as obesity, alcohol consumption and smoking.

Pancreatic cancer is an especially deadly form of cancer. It's the 12th most common type of cancer in the world, but the seventh most deadly, according to the researchers.

Pancreatic Cancer in the U.S.

Researchers examined data from 107 countries. They found the highest pancreatic cancer rates in countries with the least amount of sunlight. Low sunlight levels are due to a combination of cloud cover and high latitude.

People who live in sunlight-deficient areas have trouble making Vitamin D. The study suggests low levels of Vitamin D may contribute to the risk of pancreatic cancer.

The U.S has the world's 20th highest pancreatic cancer rate. Dr. Cedric Garland, lead author of the study, said much of the U.S. population lives at 38 degrees north of the equator.