Calcium Builds Strong Bones
~ March 1998 No.36 ~
Calcium is the most abundant mineral in the body; the bones and teeth accounting for about 99% of the total body stores. Under normal conditions, the composition of bone is relatively constant, with a calcium to phosphorus ratio of 2:1.
The process of bone building is a complex event that involves minerals and hormones that can be greatly influenced by dietary factors. Rickets, a disease common in many third world countries in infants and children, is caused by problems with calcium/phosphorus metabolism and / or low levels of vitamin D. Fortification of some foods with vitamin D has been one way of combating rickets. Loss of bone calcium is a major concern for most people, particularly women, as they age. Osteoporosis, in which the bones of the body thin, has become a major health problem. In an attempt to reverse bone calcium loss, many recent dietary recommendations have been made that encourage an increase the amount of calcium consumed per day.
Increasing calcium intake is not as easy as it may seem, particularly for those who do not like or who do not tolerate milk products. There are other dietary sources of calcium listed below. However, besides the amount of calcium in the diet, bone formation is influenced by other things such as hormones. Recent research is showing that a combination of diet and hormone treatment may be the best defense against osteoporosis.
|Compound||Chemical Formula||% of Bone Ash*|
|*Note: bone ash is approximately 55% of bone on a dry matter basis. Therefore calcium phosphate would contribute (0.84 x 55) = 46.2 % to the weight of bone dry matter.|
|Product||Serving size||Amount of Calcium|
|2% milk:||250 ml||315 mg|
|skim milk:||250 ml||317 mg|
|cheddar cheese:||45 g||324 mg|
|yoghurt (from skim milk):||125 g||203 mg|
|cod (panfried):||90 g||27 mg|
|mackerel (canned):||90 g||167 mg|
|sardines (canned):||90 g||393 mg|
|almonds:||75 g||175 mg|
|sesame seeds:||58 g||673 mg|
|broccoli:||180 g||158 mg|
|spinach:||190 g||176 mg|
|turnip:||212 g||126 mg|