Dairy's Role in Building Strong, Healthy Bones for Life
Dr. Robert Heaney

Dairy foods are an excellent source of several essential nutrients that work together to help protect bones. Researcher and bone-health expert, Dr. Robert Heaney from Omaha, Nebraska's Creighton University answers questions about milk and healthy bones, and why serving milk at school is important.

Interview Questions

• Are there certain populations in the United States that are more at risk for calcium and vitamin D deficiency?
• When do we need to start worrying about osteoporosis and bone health?
• Why are dairy foods the best foods for strengthening bones?
• How does the calcium in milk compare to calcium-fortified beverages?
• What are your thoughts on schools serving milk in plastic, resealable bottles instead of cartons?
• Can you address the nutritional value of flavored milk? And do you feel that flavored milk should be served in schools?
• Do you recommend that people who are lactose intolerant avoid eating dairy foods?

Are there certain populations in the United States that are more at risk for calcium and vitamin D deficiency?
Virtually the whole population has a relatively low calcium intake, and most of us are at risk for calcium deficiency. The same is true for vitamin D, except for infants and toddlers. They tend to get enough calcium from formula that contains vitamin D, or from vitamin D drops the pediatrician prescribes.

When do we need to start worrying about osteoporosis and bone health?
We think about people at the far end of life as having osteoporosis. But bone health is a potential problem throughout life. For example, milk-avoiding children have almost twice as many fractures before age 8 than kids who drink the recommended amounts of milk. We don't think of it as osteoporosis, but it's really not different from the little old lady who falls down and breaks a bone because she's not had enough calcium. It's a life-long problem.

Why are dairy foods the best foods for strengthening bones?
Dairy foods contain such a complete package of all of the nutrients needed for bone health, that it's difficult to match them with supplements or other foods. Together, milk, cheese, and yogurt provide nine essential nutrients, including calcium, potassium, phosphorus, protein, vitamins A, D and B12, riboflavin, and niacin. And milk costs less per calorie than other food in the diet. So you actually save money if you get your bone strengthening from milk, than if you get it any other way.

How does the calcium in milk compare to calcium-fortified beverages?
I don't think it is helpful to try to contrast the calcium in milk to the calcium in other beverages. The advantage of milk is that it is more than calcium. If we just focus on calcium, then I think we miss the importance of all the other nutrients it provides that are so important for total health. Milk provides all the nutrients a growing body, not just the bones, need. The nutrients are more densely packaged than in other food types. So if children's food intake is spotty or uncertain, milk will give them the most benefit for the least effort.

What are your thoughts on schools serving milk in plastic, resealable bottles instead of cartons?
If it is at all possible, a school should make the switch to the plastic, resealable containers. Based on a nationwide School Milk Pilot Test, we know that packaging makes a difference. In the study kids consumed more milk when it was served in plastic bottles.

Can you address the nutritional value of flavored milk? And do you feel that flavored milk should be served in schools?
I favor milk consumption because of its many nutritional benefits, and because without it we are not likely to meet the recommendation of the 2005 Dietary Guidelines for Americans to consume 3 cups of milk or milk equivalent daily. That goes for flavored milk, too. If the choice is between flavored milk and no milk, there shouldn't be any question. You've got to go with flavored milk because that's where kids are going to get the nutrient package they need. The nutritional value is essentially the same for both, and that's where we need to focus. Also, milk has been displaced by other carbonated and sweetened, fruit-flavored beverages that offer very little except taste. We need milk at school so that it doesn't get knocked off the table, as it were. It's not just a problem at school. It's a problem at home, too. We have to get milk back on the lunch and dinner tables.

Do you recommend that people who are lactose intolerant avoid eating dairy foods?
Your body can build up a tolerance to lactose over a period of only a few weeks by gradually building up your milk intake. So no, I don't recommend that people with lactose intolerance avoid dairy products. Within two or three weeks of increasing consumption, you should be able to tolerate three servings of milk per day without any symptoms. There are other "helps," too, such as Lactaid® that can be added to milk to help your body digest the sugar or lactose-reduced milk, which tastes a little sweeter. So there are lots of ways to get around lactose intolerance. Find answers to more questions about lactose intolerance.

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