Calcium can be found in diary products, leafy green vegetables, nuts and seeds (i.e. almonds, brazil nuts, and sesame seeds), tofu (bean curd) and dried fruits. Cereal, if it is fortified with calcium carbonate, is also a good source. Hard water may also provide calcium. Meat, however, is not a good source of calcium.
Other factors contribute to calcium intake. Vitamin D is essential to for absorption of calcium. Calcium is transported into the body by a special carrier protein which requires vitamin D. Furthermore, uronic acid, a component of dietary fiber, and oxalic acid, both found in certain fruits and vegetables, can help bind calcium. Conversely, some substances can hinder the absorption of calcium.
Phytic acid, found in bran, whole cereals and raw vegetables are some calcium blockers. Saturated fats can also lessen calcium absorption. Calcium is lost in faeces, urine and sweat.
Good Sources of Calcium: Tofu, cheddar cheese, cows milk, spinach (boiled), dried figs, soy cheese, chick peas (boiled), baked beans, and broccoli.
Fair Sources of Calcium: Brown bread, brazil nuts, dried apricots, French beans (boiled), cottage cheese, and sesame seeds.
Poor Sources of Calcium: Spaghetti (boiled) and brown rice.
(Consumer Healthcare, Research and Development)