Stomach cancer is one of the common cancers worldwide including developing countries and is identified as one of the most lethal among the diet related cancers. In Nigeria, there is paucity of data and information about the prevalence of stomach cancer and without doubt this disease is on the increase. Youth engage in the consumption of western diets which have been identified in the literature as one factor that is closely associated with cancers. This shift to western diets by most youth may be due to lack of nutritional knowledge on the health consequences of their eating habits. In years to come, there may be an increase in the incidence of diet -related cancers and other chronic diseases if nutrition education is not put in place especially among the youth. Not many studies in Nigeria have focused on nutrition education of the youth in relation to the prevention of chronic diseases ; prominent among which is stomach cancer. This study is aimed at providing nutrition related education to university undergraduates in order to create awareness about nutrition with a view to preventing a rise in the incidence of stomach cancer and other chronic diseases. A quasi -experimental design was used for this study. Multi -stage sampling was used to select 436 male and female undergraduates between 16 -25 years old from two universities in south- west Nigeria (one control and one experimental ). The intervention consisted of lectures on nutritional factors of stomach cancer one hour weekly for 8 weeks and a placebo lecture on HIV/AIDS stigmatization for the control group. A validated self -structured questionnaire was used to collect the data for the pretest and posttest . Demographic characteristics were analyzed with percentages; variables were analyzed using t -test and ANCOVA set at 95% confidence interval. Nutrition education improved knowledge of nutrition in the participants (p<0.00). The experimental group displayed higher nutrition knowledge compared to control . Level of study affected participants’ nutrition knowledge; students of lower level study performed better (p< 0.00). Gender also affected participants’ nutrition knowledge; females performed better than males (p<0.00). More nutrition education should be encouraged in school setting s to improve knowledge of nutrition in order to prevent a possible dietary risk of stomach cancer and other chronic diseases.