Supplements for vegans and vegetarians

Plant-based diets reliably under-deliver on five nutrients: vitamin B12 (essentially absent from plants), iron (non-heme form is 2–3× less absorbable), omega-3 EPA/DHA (algal oil is the best plant source), vitamin D3 (cholecalciferol from lichen, not D2), and zinc (lower bioavailability from grains). Calcium can be adequate from fortified plant milks but is worth tracking. Iodine deficiency is rising in vegans who avoid sea vegetables. Choline intake is lower than omnivore averages and matters in pregnancy. The list below ranks the plant-friendly supplements with the strongest published evidence for vegans and vegetarians.