[Severe macrocytic anaemia and secondary hyperparathyroidism in a vegan].

Nutritional deficiency anaemia in vegans is common and usually due to lack of vitamin B12, as this vitamin is found almost exclusively in animal-based food products. In this case report we present a 39-year-old male vegan with severe macrocytic anaemia due to vitamin B12 deficiency as well as secondary hyperparathyroidism due to severe vitamin D deficiency. We want to emphasize the importance of a detailed nutritional history for patients with anaemia, and the need for vitamin B12 and vitamin D supplements for people who comply with a vegan diet.