Parents are advised to make sure their children drink milk and eat other calcium-rich foods to build strong bones. Soon, they also may be urged to make sure their kids eat salmon, almonds and other foods high in magnesium — another nutrient that may play an important role in bone health, according to a study to be presented Sunday, May 5, at the Pediatric Academic Societies (PAS) annual meeting in Washington, DC.
“Lots of nutrients are key for children to have healthy bones. One of these appears to be magnesium,” said lead author Steven A. Abrams MD, FAAP, professor of pediatrics at Baylor College of Medicine in Houston. “Calcium is important, but, except for those children and adolescents with very low intakes, may not be more important than magnesium.”
While it is known that magnesium is important for bone health in adults, few studies have looked at whether magnesium intake and absorption are related to bone mineral content in young children. This study aimed to fill that gap.
Researchers recruited 63 healthy children ages 4 to 8 years old who were not taking any multivitamins or minerals to participate in the study. Children were hospitalized overnight twice so their calcium and magnesium levels could be measured.
Participants filled out food diaries prior to hospitalization. All foods and beverages served during their hospital stay contained the same amount of calcium and magnesium they consumed in a typical day based on the diaries. Foods and beverages were weighed before and after each meal to determine how much calcium and magnesium the subjects actually consumed. In addition, parents were given scales to weigh their child’s food for three days at home after the first inpatient stay and for three days at home prior to the second inpatient stay so that dietary intake of calcium and magnesium could be calculated accurately.
While hospitalized, children’s levels of calcium and magnesium were measured using a technique that involved giving them non-radioactive forms of magnesium and calcium, called stable isotopes, intravenously and orally. Urine was collected for 72 hours. By measuring the stable isotopes in the urine, the researchers could determine how much calcium and magnesium were absorbed into the body. Bone mineral content and density were measured using total body dual-energy X-ray absorptiometry.
Typically, when parents think about their children’s health, they don’t think about their bones. But building healthy bones by adopting healthy nutritional and lifestyle habits in childhood is important to help prevent osteoporosis and fractures later in life.
Osteoporosis, the disease that causes bones to become less dense and more prone to fractures, has been called “a pediatric disease with geriatric consequences,” because the bone mass attained in childhood and adolescence is an important determinant of lifelong skeletal health. The health habits your kids are forming now can make, or literally break, their bones as they age.
Why Is Childhood Such an Important Time for Bone Development?
Bones are the framework for your child’s growing body. Bone is living tissue that changes constantly, with bits of old bone being removed and replaced by new bone. You can think of bone as a bank account, where (with your help) your kids make “deposits” and “withdrawals” of bone tissue. During childhood and adolescence, much more bone is deposited than withdrawn as the skeleton grows in both size and density.
For most people, the amount of bone tissue in the skeleton (known as bone mass) peaks by their late twenties. At that point, bones have reached their maximum strength and density. Up to 90 percent of peak bone mass is acquired by age 18 in girls and age 20 in boys, which makes youth the best time for your kids to “invest” in their bone health.
Results showed that the amounts of magnesium consumed and absorbed were key predictors of how much bone children had. Dietary calcium intake, however, was not significantly associated with total bone mineral content or density.
“We believe it is important for children to have a balanced, healthy diet with good sources of minerals, including both calcium and magnesium,” Dr. Abrams concluded.
Keep Dairy Handy
A recent study reveals that teens ages 14 to 18 typically down 18 ounces of soft drinks daily, which is more than double their milk intake. To help your teen meet his calcium quota, encourage him to have at least four 1-cup servings of dairy a day. Stock up on yogurt, yogurt smoothies, low-fat string cheese, and calcium-fortified cereal bars. Besides providing a healthy dose of calcium and vitamin D, dairy products offer a package of nutrients- including riboflavin, phosphorus, potassium, protein, zinc, and essential amino acids - all of which aid bone development.
If your teen is lactose intolerant, try having her build up her tolerance by consuming small amounts of milk with food, such as a half-cup of milk on cereal, then gradually increasing amounts. According to the American Academy of Pediatrics, teens with lactose intolerance should still drink as much milk as they can tolerate. “Drinking milk fosters good bacteria in the intestine that digests lactose,” explains Robert P. Heaney, M.D., professor of medicine at Creighton University, in Omaha. Lactose-free milk is also an option, as are dairy products with low levels of lactose, such as cheddar and Swiss cheeses and yogurt containing active cultures.
The Pediatric Academic Societies (PAS) are four individual pediatric organizations that co-sponsor the PAS Annual Meeting – the American Pediatric Society, the Society for Pediatric Research, the Academic Pediatric Association, and the American Academy of Pediatrics. Members of these organizations are pediatricians and other health care providers who are practicing in the research, academic and clinical arenas. The four sponsoring organizations are leaders in the advancement of pediatric research and child advocacy within pediatrics, and all share a common mission of fostering the health and well-being of children worldwide.
American Academy of Pediatrics