Some elements affect the development of the body. For example iodine affects height (higher amounts make you taller) and makes the body more resistant to radiation. In the case of food, it mostly depends on your metabolism. If you have a very fast metabolism (like me) than you could eat the whole market, you still wouldn't gain any wight. If you have a slower metabolism, it may be harder to lose weigh. Of course all vegetables, fruit and other food contain vitamins and minerals, which are vital to our health. Calcium (contained in high amounts in milk and dairy products) is used to develop bones, teeth and nails. A lack of this element can cause weaker bones. A sign of calcium deficiency are small white lines or your nails. Iron is another important element (contained in high amounts in spinach (bleh!) and red meat). Iron deficiency make the body weaker, and more susceptible to illnesses. It is also known as anemia. Of course there are many other factors too.