Poster Topical Area: Vitamins and Minerals
Location: Hall D
Poster Board Number: 492
Objective: The goal of this study was to evaluate the impact of whole egg and egg components in growing rats fed a methyl group-restricted diet.
Methods: Five wk old, male Sprague Dawley rats (N=48) were randomly assigned to one of four modified AIN-93 dietary treatment groups: a casein-based diet (n=12), a casein-based diet supplemented with choline (1.3%) (n=12), an egg white protein-based diet (n=12), or a whole egg-based diet (n=12). All diets provided protein at 20% (w/w). Corn oil was added to both casein-based diets, as well as the egg white protein-based diet to account for the additional lipid contribution of the whole egg (17.7% total lipid). At wk 2, half of the rats in each dietary group were assigned to a folate-restricted (FR) diet for the remainder of the 8 wk study period. Folate restriction was achieved with a custom-formulated vitamin mix devoid of folate. Rats were given ad libitum access to food and water for the duration of the study and body weight was recorded daily 5 days/wk. Mean values were compared using a two-way ANOVA (P< 0.05) followed by the Tukey's Honest Significant Difference (HSD) post hoc test for multiple comparisons.
Results: Cumulative body weight gain did not differ in rats fed the casein-based diet, the casein-based diet supplemented with choline or the whole egg-based diet, regardless of dietary folate status. Rats fed a FR egg white protein-based diet gained 18% (P = 0.04) more weight than their respective folate-sufficient controls.
Conclusions: These data suggest that a methyl-restricted diet results in greater weight gain in growing rats fed an egg white protein-based diet, which may reflect epigenetic changes which ultimately impacts phenotype, including body weight.
Iowa State University