No- in fact, quite the opposite. Studies have shown that cooking food in cast iron can significantly increase the iron content of the food- but many Americans don’t get nearly enough iron in their diet- which can lead to iron deficiency anemia- the most common nutrient deficiency in the world, especially for women. So, while too much iron can theoretically hurt you, it’s such a rare occurrence that it’s a negligible factor, and in fact, using cast iron appliances can actually make you healthier.