Almost everyone has seen the advertising slogan "Got Milk?" Famous actors, rock stars, and athletes are seen on TV, in magazines, and on billboards sporting a "milk mustache" and promoting milk as a healthy beverage choice. And with good reason!
Milk is an important source of calcium, a mineral that may be in short supply in the diets of some of our children. Recent studies reveal that few American children are meeting all of the recommendations outlined in the U.S. Department of Agriculture (USDA) Food Guide Pyramid and the Dietary Guidelines for Americans, especially for dairy products. In fact, a study in 1997 of more than 3,000 children showed only one percent of these children met their daily calcium recommendations.
Calcium is essential for the formation of bones and maintenance of bone strength necessary for physical activity throughout life. Bone mass is developed during childhood through young adulthood, with an estimated 40-45 percent of development during adolescence. By age 20, adult bone mass is almost fully formed. After early adulthood, calcium in the bones can be lost, but not replaced. Adequate intake of calcium to build strong bone mass early in life can help prevent osteoporosis, a condition in which bone mass and density is lost, leading to increased risk of bone fractures.
Calcium also is important for the proper functioning of the heart, muscles, and nerves, and it helps maintain healthy blood flow. A diet rich in low-fat dairy foods, fruits, and vegetables can help lower blood pressure, and some studies suggest that certain components of milk and other dairy foods may reduce the risk of breast and colon cancer.
Diet and Early Childhood
Unfortunately, many children and teens do not get adequate calcium in their diets. According to the USDA, 80 percent of teen girls and 60 percent of teen boys do not consume enough calcium to maintain good health. Furthermore, many preadolescent and adolescent females who are concerned about body weight abstain from dairy products to reduce their fat intake. During the last 30 years, milk consumption declined 23 percent in the U.S., while consumption of carbonated beverages increased 188 percent. The heavy soft drink consumption by our nation's youth is even more troubling because the phosphorus in many carbonated beverages affects the calcium metabolism of the body, causing a calcium-phosphorus imbalance and contributing to bone loss. Caffeinated soft drinks also may play a role in bone loss because caffeine causes the body to excrete extra calcium through the urine.
Alternatives to Dairy Products
Some children may be unable to consume milk and dairy products due to allergies or other conditions. However, there are other ways to meet the USDA's recommended levels of calcium intake.
Lactose intolerance is a problem for individuals who have an absence or relative deficiency of the enzyme lactase, which is necessary to digest the milk sugar called lactose. The inability to digest lactose varies among individuals. The symptoms of lactose intolerance generally appear around age 3 or 4, when the child's body gradually stops producing lactase. Symptoms may include bloating, flatulence, cramps, nausea, and diarrhea.
Many children who are lactose intolerant also are intolerant of soy products. Therefore, it is important for caregivers, parents, and children to become label readers so they can identify terms that indicate the presence of milk and other foods linked to intolerance. Also, some children have only a partial lactose intolerance and therefore can digest milk and other dairy products in small amounts. Reduced-lactose milk is widely available as are lactase enzyme preparations that can be added to milk and other dairy foods to make lactose digestible. In addition, aged cheeses and yogurts usually are acceptable because lactose is broken down in the manufacturing process.
There are other non-dairy foods that contain calcium. For example, an 8-oz glass of calcium-fortified orange juice contains at least as much calcium as an 8-oz serving of milk. A variety of breakfast cereals and breads are fortified with calcium. Also, for children in families that practiced vegetarianism or for young adults who choose not to eat meat or other animal products, tofu and certain types of beans are excellent sources of calcium. Dark green leafy vegetables are low in calories and contain healthy doses of calcium; however, it takes at least five servings of collards a day to get the same amount of calcium that is in 3-4 glasses of milk. For children who will not drink milk and do not consume enough calcium, many pediatricians suggest that parents give children a daily calcium supplement, which is available without prescription.
Calcium intake also may be affected in children with Phenylketonuria (PKU), a genetic metabolic disorder in which the amino acid phenylalanine cannot be used properly. PKU has been associated with mental retardation, hyperactivity, irritability, and seizures. Dietary management of PKU requires balancing phenylalanine, protein, and caloric intake, and foods containing large amounts of protein such as meats, legumes, eggs, and dairy products, as well as foods containing aspartame, are omitted from the diet.
Encourage Calcium Consumption
Many health experts recognize inadequate calcium consumption among children and teens to be a growing problem and a serious threat to their healthy growth and development. Childcare providers and parents play a key role in helping young children learn the knowledge and skills necessary for healthy dietary behaviors, which includes teaching young children the importance of eating well and consuming adequate calcium to build strong bones. The following tips are important for helping children build strong bones:
Marilyn Massey-Stokes, Ed.D., CHES, Associate Professor, Texas Tech University and
- Talk about the importance of developing healthy eating habits at an early age.
- Teach the importance of eating enough calcium-rich foods each day, including low-fat or non fat dairy products and calcium-fortified orange juice.
- Provide nutritious meals and snacks that include calcium-rich foods.
- Avoid fast food, which generally is low in calcium.
- Encourage kids to drink fewer soft drinks and other caffeinated beverages.
- Promote regular physical activity, particularly weight-bearing exercises such as walking, jogging, aerobics, etc.
- Be a positive role model! Practice nutritious eating habits, and be physically active.
Pamela David, R.D., Nutrition Consultants, Birmingham, AL
Milk Matters Calcium Education Campaign, 31 Center Dr., Room 2A32, Bethesda, MD 20892-2425; 301-496-5133; www.nichd.nih.gov/milk/milk.cfm
National Dairy Council, 10255 W. Higgins Rd., Suite 900, Rosemont, IL 60018;
National Institute of Child Health and Human Development, www.nichd.nih.gov/milk/milk_facts.htm
Keep Kids Healthy, www.keepkidshealthy.com/nutrition/calcium.html
Kids Health, kidshealth.org/parent/food/general/calcium.html