Hypotheses concerning roles of dietary energy, cured meat, and serum tocopherols in adult glioma development

We conducted a pilot study to determine whether: (1) high levels of energy intake increase glioma risk; (2) the previously observed relationship betwe en cured meat consumption and glioma risk can be attributed to confounding by energy intake, and (3) alpha-tocopherol modifies caloric intake and gamm a-tocopherol modifies cured meat consumption. We identified 40 age-sex-race matched glioma sets, and obtained serum vitamin C and alpha- and gamma-toc opherol levels for 23 of these sets. Glioma risk increased with quartile of total dietary energy adjusted for fat, protein, and nitrite-containing mea t consumption (odds ratio = 1.0, 2.7, 5.8, 8.2; p value for trend test = 0. 02). Although positive associations between individual cured meats and glio ma risk decreased when adjusted for caloric intake, the small sample size m akes it difficult to interpret the results. Serum alpha-tocopherol appeared to modify the effect of calories and serum gamma-tocopherol may modify the effect of cured meat on glioma risk. While the observed interaction is pre dicted by experimental research, our findings are based on small numbers. L arger studies are needed to further evaluate our preliminary findings.