A study published in Nutrition Today finds naturally calcium-rich milk is the most reliable source of this bone-building nutrient, superior to calcium-fortified soy and rice beverages and many orange juice brands.

The study reveals that much of the calcium settles to the bottom of fortified soy and rice beverage containers, even after vigorous shaking. Researchers say that simply adding calcium to beverages does not make them nutritional substitutes for milk. In addition to calcium, milk provides protein, phosphorus, vitamins A and D, and many other nutrients.

"The calcium that you'll find added to many soy beverages will have settled to the bottom of the container," said Robert P. Heaney, MD, FACP, FACN, Osteoporosis Research Center at Creighton University, Omaha, Neb.

"Hand shaking wasn't enough; we found that really vigorous shaking, such as with a hardware store paint shaker, would have been needed to suspend the calcium in these beverages so you can put them in the glass and drink them," said Heaney.

This study shows that the nutrition label for milk is accurate for calcium in that the amount listed on the label is the same as what is actually in a glass of milk.

With 85% of shoppers looking at the Nutrition Facts Label when choosing which foods to buy, and almost eight out of ten Americans not meeting their calcium requirements, this information is critical for health-conscious shoppers.

In this study, milk scored higher than all four soy or rice beverages, and eight of ten orange juice products. Scores comparing calcium liquid suspension for two of the orange juice products were nearly the same as milk. Due to the inconsistent quality of calcium-fortification in soy/rice beverages and orange juice brands, the researchers concluded milk is the most reliable calcium source.