Your body can absorb this vitamin more easily in a soluble powder form than in a large tablet. I take a dose of vitamin C with breakfast and dinner, or before bed. Plain ascorbic acid may irritate a sensitive stomach, so take it with food or look for a buffered or nonacidic form. Since vitamin E is fat soluble, it must be taken with food to be absorbed. I usually take vitamin E at lunch.
Selenium is a trace mineral with antioxidant and anticancer properties.
Selenium and vitamin E facilitate each other's absorption, so take them together. Vitamin C may interfere with the absorption of some forms of selenium so take them separately. Doses above 400 micrograms a day may not be healthy. I take mixed carotene as a supplement with my breakfast. Read the label to make sure it gives you lycopene , the red pigment in tomatoes that helps prevent prostate cancer.