Healthnotes Newswire (September 28, 2000)—According to a study published this month in the journal Cancer, certain dietary factors and a vitamin may influence the survival rate of people with stomach cancer.¹

In this study, a group of 382 patients with stomach cancer were interviewed about their diet in the year prior to their cancer diagnosis. These patients were then followed over the next ten years, and survival statistics were collected.

The authors of the study found that patients who were in the top 33% for alcohol intake had a 40% lower chance of surviving the ten-year follow-up period. Alternatively, patients in the top one-third for vitamin E intake were 25% more likely to survive for ten years. Other dietary factors, including total dietary fat, animal fat, sugar, and vitamin C, did not correlate with chances of survival.

When researchers considered only patients with a family history of stomach cancer, survival rates decreased dramatically in the patients whose diets were in the top one-third for animal protein, animal fat, and N-nitrosodimethylamine (a chemical formed in the cooking of meats). However, mortality rates were decreased by 50% in patients with a family history of stomach cancer if they were in the top one-third for vegetable fat or starch intake.

Although substantial evidence exists showing alcohol intake not to be a clear risk factor for the development of stomach cancer,² this is the first study to show a correlation between drinking and poor prognosis. This is also the first study to show a relationship between dietary vitamin E and improved chances of survival from stomach cancer. Supplemental vitamin E, when administered together with selenium and beta-carotene, has already been shown to reduce stomach cancer risk.³

Perhaps the most important finding of this study was the correlation of animal-fat intake with worse outcomes in the patients with a family history of stomach cancer. There is a growing body of research showing that animal fat is associated with worse outcomes from other types of cancer, including prostate,⁴ breast,⁵ and pancreatic cancer.⁶

This new study is the first to suggest that the relationship between dietary animal fat and cancer outcome is limited to a specific subset of cancer patients. The reason for this finding is unclear. The authors theorized that the lack of association between animal-fat intake and survival among patients without a family history of stomach cancer was a statistical aberration, due entirely to chance.

This type of observational study, along with other studies that have examined the relationship between dietary animal fat and cancer outcomes, is considered only preliminary evidence. The weakness of this study is that it did not assess whether changing the diet after the cancer diagnosis would affect survival. Regardless of the limitations of this new study, it can be considered another piece of evidence that dietary factors do indeed influence the prognosis of cancer patients.

The effects of alcohol and vitamin E consumption on stomach cancer prognosis may be good news to the 21,500 Americans who will be diagnosed with stomach cancer this year.⁷ Currently, only 21% of those diagnosed with stomach cancer will survive for five years after diagnosis.⁸ But perhaps even more important is the association between dietary intake of animal fats and survival. Even today, the suggestion that diet can influence the outcomes of cancer treatment remains controversial. However, with this new study, along with the many others that confirm its findings, the evidence that diet is a major factor in the prognosis of cancer patients becomes increasingly difficult to ignore.