While preliminary research from Australia suggests a correlation between sun exposure and lower rates of pancreatic cancer, this most recent study only adds to the conflicting data linking the two.
Rachel Neale, PhD, of Queensland Institute of Medical Research in Australia, presented the study results at a pancreatic cancer conference held by the American Association for Cancer Research in Lake Tahoe, Nev., in July.
Neale and colleagues looked at pancreatic cancer rates and possible sun exposure in 714 people in Queensland, Australia, between 2007 and 2011 and compared them with a similar control group. The study concluded that participants born in areas with high levels of ultraviolet radiation (UV) rays from the sun had a 24 percent lower risk for pancreatic cancer compared with those born in areas of low UV radiation. It is important to note that these results may be due to methodological issues, Neale says.
Vitamin D, which the body activates from sun exposure or receives through food or beverage consumption, may also play a role. However, other studies examining vitamin D show it may increase the risk of pancreatic cancer.
To explain the conflicting infor-mation, Neale says that if high exposure of UV rays from the sun decreases the risk of pancreatic cancer, it may be acting independently of vitamin D, and more research is needed to understand how these results can be used. In the meantime, Neale suggests following recommended guidelines for vitamin D intake and limiting sun exposure.
In the U.S., the recommended daily allowance for vitamin D is 600 international units (IUs) for most people and 800 IUs for those above age 70. Ten minutes of sun exposure at midday can produce about 10,000 IUs of vitamin D.
“At this stage we are still uncertain about the beneficial effects of sun exposure,” Neale says. “We are much more confident that sun exposure causes skin cancer than we are that it protects from pancreatic cancer or other cancers.”