Bones are living organs that are strengthened by stores of calcium and other minerals. However, other parts of your body need those minerals, too. If your diet doesn't provide enough, your body will simply take them from the supply in your bones, according to the 2004 Surgeon General's Report on Bone Health and Osteoporosis. Your body needs Vitamin D to absorb calcium properly. Fat-free or low-fat milk is a good source of calcium because milk has a lot of calcium, and most milk is "fortified" or contains added Vitamin D.
Calcium
The optimal years for building strong bones are between the ages of 9 and 15 years, according to the National Institutes of Health, but it's never too early or too late to provide good care for your bones. About 90 percent of adult bone mass has been built by the time you're 17 years old, but bones continue to build density until you're about 30. Calcium helps you build bones and keeps them strong throughout your life, and milk is a good source of calcium.
Vitamin D
Your body needs vitamin D for calcium to work. Vitamin D is absorbed through the skin from sunlight but many people do not get sufficient vitamin D from the sun alone, according to the 2004 Surgeon General's Report on Bone Health and Osteoporosis. Vitamin D is found naturally in tuna fish, liver and fish liver oils. Many food products contain added vitamin D, including most milk. Check food labels to see if vitamin D is an ingredient and at what percent DV. One serving of vitamin D-fortified milk contains 100 International Units, half the federal minimum daily recommended amount for kids to 50-year-old adults. From age 51 to 70, people require twice the DV, or 400 IU; and for people ages 71 years and older, 600 IU, or 300 percent DV, is recommended.
Serving Size
Kids aged 9 to 15 years old need more calcium during critical growth-spurt years. Fewer than 10 percent of girls and just 25 percent of boys between 9 and 13 get enough calcium in their diets, according to the National Institutes of Health. The organization recommends that 9-to-18-year-old children receive at least 1,300 mg of calcium a day, or 130 percent of the recommended daily value. Women over the age of 50 should get at least 1,200 mg a day, or 120 percent DV. One serving size of one cup of low-fat or fat-free milk contains about 300 mg of calcium. Children and teens can get most of the calcium they need by drinking three cups of low-fat or fat-free milk.
Lactose Intolerance
You may be unable to drink milk if your body is unable to digest lactose, a natural sugar found in dairy products. If you get an upset stomach, cramps, bloating, diarrhea or gas after eating a dairy product, you may be lactose intolerant. The condition isn't common in young children and is even less likely if milk and dairy foods are taken along with meals, but talk to your child's pediatrician if you see symptoms that might indicate a problem. If a member of your family is lactose intolerant, you can still provide meals containing enough calcium and Vitamin D by offering non-dairy foods such as lactose-free or lactose-reduced milk; fortified soy or rice products; dark green vegetables such as spinach, bok choy, kale, collards and broccoli; and other fortified foods such as juice, tofu, breakfast cereal and bread.
Alternatives
You can supplement your diet with multivitamins that contain calcium and vitamin D, but it's a good idea to check with your doctor before taking them. Your body is able to absorb vitamins and minerals better from food than pills. Check food labels when you shop for groceries. Foods with at least 20 percent DV are considered high in nutrients like calcium and vitamin D; foods with 5 percent DV or less are considered low. Dark green vegetables such as broccoli, spinach, bok choy, kale, collards and fortified products such as tofu, juice, bread and breakfast cereals can be good sources of calcium. Good sources of vitamin D include tuna fish, liver, fish liver oils and fortified foods.
Controversy
The benefits of milk have been questioned. The Physicians Committee for Responsible Medicine reported in a June 2007 publication that studies have shown that levels of physical activity in youngsters may have more effect on adult bone development than calcium intake. A 12-year Harvard study found that women who drank more milk actually broke more bones than women receiving calcium from alternate sources. Similar studies have found much the same, indicating that other elements found in dairy products, such as animal proteins and salt, may actually accelerate calcium loss. Talk to your doctor if you have concerns.
