Not that long ago, a doctor might have said that the cause of pancreatic cancer was “bad luck.” In other words, it wasn’t known. But a recent study in the Journal of the National Cancer Institute sheds light on the link between pancreatic cancer risk and diet.
Cancer of the pancreas is one of the most deadly forms of the disease. It’s the fourth leading cause of cancer deaths. Five-year survival rates are about three to five percent. The average survival period after diagnosis is just four to six months.
Researchers from the Division of Cancer Epidemiology and Genetics at the National Institutes of Health evaluated the diets of 527,218 participants in the NIH-AARP Diet and Health Study. The subjects, who were aged 50 to 71 years old, answered food frequency questionnaires. The researchers compared their responses to the 2005 Dietary Guidelines for Americans.
According to the NIH study, people whose diet conformed most closely to the 2005 Dietary Guidelines had a 15% lower risk of pancreatic cancer compared to those whose diet conformed least to the guidelines. That was after taking into consideration other known pancreatic cancer risk factors such as smoking and diabetes.
The association was stronger among overweight or obese men compared to normal weight men. But the association among women was not affected by weight.
There is a newer version of the Dietary Guidelines for Americans. While they may be an improvement over the standard American diet (SAD), the Dietary Guidelines have come under criticism. Critics claim they are based less on science and more on the lobbying of efforts of various food industry interests, particularly the dairy, sugar and meat industries.
Clearly, as the researchers noted, the guidelines are not designed specifically for the purpose of overall cancer prevention. Nevertheless, the study authors believe their findings support the “hypothesis” that a high quality diet may play a role in reducing pancreatic cancer risk.
What kind of diet might help prevent pancreatic cancer?
Recently, researchers at UCLA's Jonsson Comprehensive Cancer Center found that mice fed a high calorie, high-fat diet developed abnormally high numbers of certain lesions known to be precursors to pancreatic cancer.
The study published in the journal Cancer Prevention Research found that mice fed a normal diet had mostly normal pancreases. But mice fed the high-fat, high-calorie diet gained significantly more weight, developed metabolic abnormalities, and had increased insulin and inflammation levels. They also developed significantly more pre-cancerous pancreatic lesions.
Dr. Nicholas Gonzalez, a pioneer in using diet to treat pancreatic cancer, would argue that no one diet is appropriate for all people. Rather than focusing on fat or calories, Dr. Gonzalez believes that some people benefit from acid diets and some from alkaline diets. The choice depends on whether their sympathetic or parasympathetic nervous system is dominant.
What foods fight pancreatic cancer?
Many common foods contain certain flavonoids that kill human pancreatic cells in the lab.
In one study from the University of Illinois, researchers pretreated aggressive human pancreatic cell lines with apigenin for 24 hours before applying a chemotherapeutic drug. In another study the flavonoids were used without chemo drugs.
The apigenin inhibited an enzyme which decreased anti-apoptotic genes in the pancreatic cancer cells. Apoptosis means that the cancer cell self-destructs because its DNA has been damaged. In other words, the apigenin allowed more apoptosis to occur.
In one of the cancer cell lines, the number of cells undergoing apoptosis went from 8.4% in untreated cells to 43.8% in cells treated with apigenin, even before any chemotherapy drug.
Although the researchers do not believe that pancreatic cancer patients could eat enough flavonoid-rich foods to reach effective levels for treatment, they said prevention is a different matter.
Eating lots of fruits and vegetables throughout your life gives what they called a “chronic exposure” to these flavonoids, which would certainly help to reduce the risk of cancer.
Foods rich in apigenin and luteolin include:
- Chinese cabbage
- bell peppers
- red wine
Herbs rich in apigenin and luteolin include: