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Giving children foods to which people added calcium to help build up their bones may be a waste of time, say experts. The mineral is added to many breakfast cereals, snack bars and drinks as producers can attract the parental market. But scientists have found that such products do not produce significantly stronger bones, nor do they reduce the chance of a child suffering fractures （骨折）. 　

It is thought that calcium unnaturally added to food passes through the body too quickly to be properly absorbed and therefore fails to perform the same functions as foods which are naturally rich in calcium, such as milk, cheese and leafy green vegetables.

It is now built into such things as Kellogg’s Coco Pops, breakfast bars such as the Frosties Cereal and Milk bar, some Tropicana orange juices and even the calcium-enriched water called Danone Activ.

The theory is that if children build strong bones, it will protect them better against problems such as osteoporosis in later life. But the research casts doubt on the usefulness of such products.

Experts analyzed 19 studies where children aged between 3 and 19 were given extra calcium in their diet in this way. They then measured the effect by measuring their bone mineral density and mineral content. The team found few significant increases in bone mass and none in the two bones which can most likely lead to fracture — the lower spine （脊骨） and upper part of the thigh （大腿）.

A small effect was noted in bone density in the arm, but it cut the risk of fracture by just 0.2 percent, according to the report published in the Cochrane Library. The influential publication is produced by the International Health Research Organization, the Cochrane Collaboration. The chief researcher Professor Frank R Greer of the University of Wisconsin said the findings for children prove the same as those seen in adult studies. “You can get some short-term improvements but as soon as you stop the supplements it goes right back to where it was,” he said.

1．According to the text, food with added calcium can _________.

       A．increase the bone mass significantly

       B．put a mass of calcium in the lower spine and upper part of the thigh

       C．satisfy the parents’ desire to make their children healthy

       D．make the children’s bones significantly stronger to let them suffer no fractures

2．Which of the following is TRUE about the food to which calcium is added? 

       A．Calcium in it has more effect on children than on adults.                   

       B．Your bones will be too strong to break as a consequence of it.           

       C．It can increase the mass of the lower spine and the thigh effectively.  

       D．If you stop eating it, the effect on your bones will disappear.

3．Experts hold a _________ attitude towards the food to which people added calcium. 

       A．positive               B．negative               C．neutral                           D．not clear

4．Which kind of food is naturally rich in calcium? 

       A．Kellogg’s Coco Pops                            B．Frosties Cereal and Milk bar

       C．leafy green vegetables                          D．Danone Activ