Well calcium is very important for your body it helps by building strong bones and teeth. Calcium also plays an important role in muscle contraction, transmitting messages through the nerves, and the release of hormones. If people aren't getting enough calcium in their diet, the body takes calcium from the bones to ensure normal cell function, which can lead to weakened bones.
Iron is an important component of hemoglobin, the substance in red blood cells that carries oxygen from your lungs to transport it throughout your body. ... If you don't have enough iron, your body can't make enough healthy oxygen-carrying red blood cells. A lack of red blood cells is called iron deficiency anemia... hope this helps