Some of these coagulants contain calcium compounds, thereby increasing the calcium content of the tofu. People wishing to include soy products in their diet for calcium benefits should check the labelling on the product for details of calcium content. Calcium is also now being added to a large variety of food products, including bread, breakfast cereals and orange juice. Although it is best to obtain calcium from foods containing it naturally, fortified products can provide a useful contribution to one's daily calcium intake. The amount of calcium absorbed through dietary intake depends on a range of factors, including the presence of other essential nutrients like Vitamin D. Vitamin D plays an important role assisting in the absorption of calcium from the intestinal wall.
Vitamin D is manufactured by the skin as a response to ultraviolet light in sunlight.
The best time to do this is during the early morning, mid-morning or late afternoon, so as to minimise sun damage to the skin. In Australia, most people are able to obtain enough Vitamin D through sun exposure, but there are a number of exceptions. Elderly people, particularly residents in nursing homes, may be confined indoors for a great deal of time and, therefore, miss out on adequate sun exposure. During winter, the shorter days provide less opportunity for people to gain a significant amount of sun and wearing more clothing cover reduces the amount of skin that is exposed. People who are unable to gain enough sun exposure for their daily Vitamin D requirements need to rely on dietary sources of Vitamin D or take supplements.