The nutrient essential for the production of red blood cells is vitamin B12. This vitamin plays a critical role in the formation and maturation of red blood cells, along with folate and iron. Adequate B12 levels are essential to prevent anemia and maintain optimal energy levels. Vitamin B12 is primarily found in animal products, such as meat and dairy, making it particularly important for individuals following plant-based diets to consider supplementation or fortified foods. Ensuring sufficient intake supports overall health.