Research into possible plant food sources of B12 have found that either no significant amount of B12 is present or that any B12 present is a structurally similar analogue that cannot be utilised by the body. Vegetarians generally obtain adequate B12 from dairy products. Vegans tend to have lower vitamin B12 intakes which may or may not reach recommended levels. Vegans should be advised to ensure their diet includes foods that are fortified with vitamin B12. A range of vitamin B12 fortified foods is available, including yeast extracts, vegetable stocks, vegetable burger mixes, soya milks , margarines, breakfast cereals and herbal soft drinks.
Vitamin D is present in vegetarian diets in dairy products .
Vegans tend to have low vitamin D intakes, fortified margarines being the main dietary source. However, it is assumed that sufficient amounts of the vitamin can be obtained by dermal synthesis due to the action of sunlight on exposed skin. Vegans or vegetarians consuming limited dairy products and who are not exposed to sunlight may be advised to take supplementary vitamin D. Groups at risk of insufficient vitamin D include infants and elderly persons confined indoors. Vegans should ensure their diet includes other sources of riboflavin. Studies of the mineral status of vegetarians have concentrated on iron and zinc , meat and meat products being a major source for both of these minerals.