Study Shows Selenium May Protect Against Pancreatic Cancer

Pancreatic cancer is particularly lethal. It tends to be diagnosed only in advanced stages and 80% of patients die within a year of diagnosis. Statistics show that only 5% of pancreatic patients are still alive five years after diagnosis. In the US, it is the fourth leading cancer in terms of mortality. For 2011, the National Cancer Institute estimated 44,030 new cases of the disease and 37,660 deaths from this form of cancer.

Nail clippings reveal trace elements
The Gut article was based on a study looking at patients with exocrine pancreatic cancer, the most common form of the disease. An international research team analyzed trace element levels in the toenails of 118 pancreatic cancer patients, comparing them with 399 hospital patients without cancer. Researchers choose this method because nails, especially toenails, are believed to be the most reliable indicators of trace element levels.

Selenium and Nickel Among Non-Cancer Group
Patients without cancer exhibited high levels of selenium in their toenail clippings. Selenium boosts immune system function and reduces inflammation. Previous studies have shown selenium can inhibit the growth of cancer cells. Brazil nuts, sunflower seeds, broccoli, spinach, oily fish like tuna and sardines, molasses, mushrooms and garlic are all good sources of selenium. Levels of selenium can also vary geographically. Produce and livestock grown in regions with a high selenium concentration in the soil contain more of this element.

In addition to the selenium, researchers also found higher levels of nickel among the toenail clippings of the patients who did not have pancreatic cancer. Nickel enables dietary iron absorption and contributes to the development of red blood cells. Good food sources of include lentils, asparagus, oats, mushrooms, beans and pears. Patients with the highest levels of nickel and selenium were between 33 per cent and 95 per cent less likely to have pancreatic cancer compared with those with the lowest levels. The positive influence of selenium and nickel appeared to be unchanged even after researchers accounted for other known risk factors such as smoking, diabetes, and obesity.

Arsenic and Cadmium Among Cancer Group
On the other hand, researchers found high levels of lead, arsenic and cadmium among the cancer group. They determined that high levels of lead were six times more likely to occur among cancer patients than those without cancer. High concentrations of arsenic and cadmium were two to three times more common among the pancreatic cancer sufferers. The high cadmium levels relate to cigarette smoking as this element is present in tobacco. Health experts believe as many as one-third of all pancreatic cancer cases are linked to smoking.

In the Gut article, the researchers wrote "Our results support an increased risk of pancreatic cancer associated with higher levels of cadmium, arsenic and lead, as well as an inverse association with higher levels of selenium and nickel." They suggested that clinical trials directly test selenium as a preventative measure for people at high risk of pancreatic cancer.