A common nutrient deficiency in vegan diets is vitamin B12. This vitamin is primarily found in animal products, so individuals following a vegan diet must find alternative sources or consider supplementation. B12 is crucial for maintaining nerve function and producing red blood cells. Vegans can obtain B12 from fortified foods, such as plant-based milk and cereals, or take B12 supplements to meet their needs. Ensuring adequate levels of this vitamin is vital to prevent anemia and other health issues associated with deficiency, making awareness and education about B12 sources essential for vegans.