Consumption of milk, and therefore intakes of calcium, is falling at the expense of sweetened beverages, according to a new US study.
It children between the ages of three and seven tend to consume more sweetened beverages, such as cola, juice, and juice drinks, then they consume significantly less milk, and have lower intakes of calcium and vitamin D, two essential micronutrients, according to findings published in this month’s Journal of the American Dietetic Association.
“The possibility that children who over-consume sugar-sweetened beverages may do so at the detriment of essential nutrients such as calcium and vitamin D warrants further investigation,” wrote lead author Kathleen Keller from Columbia University in New York.
“This is of great nutritional concern because calcium and vitamin D work together as key nutrients in achieving optimal bone health.”
As the dairy industry continues to promote its products as a key source of healthy dieting, research linking milks, cheeses, whey and yoghurts to improved health is increasingly being sought.
Osteoporosis is one such area being focused on by the industry. The disease is characterised by low bone mass, which leads to an increased risk of fractures, especially in the hips, spine and wrists.
Keller and her co-workers recruited 126 twins aged from three to seven, and performed two experiments in order to investigate if a relationship existed between consumption of sweetened beverages and milk (and calcium), and if such a relationship was linked to a child’s age and weight status.
The children were given ad libitum lunches and allowed to choose between a variety of sugar-sweetened and calcium-rich beverages.
A negative relationship between sweetened beverage intake and milk intake was observed, with more sweetened beverages meaning less milk, and vice versa. A negative relationship was also observed between sweetened beverage intake and calcium intake.
When the researchers considered the age of the children, they found that the older the child, the lower the milk intake, and the higher the intake of sweetened beverages.
“These intriguing findings should be interpreted with caution,” wrote Keller. “Intake of a test meal may not reflect children’s usual intake, and thus foods and nutrients consumed at these meals may not be good predictors of long-term consumption or health risk.”
Despite such limitations, the researchers added: “It was surprising that such low intakes of milk were recorded in children that were, on average, not yet 5 years old and who consumed the meal with their mothers present.
“Mean energy consumption from milk at the meal was approximately 24 kcal and intake of calcium was approximately 200 mg. If this is representative of children’s usual consumption, the recommended adequate intake of 800 mg/day for this age group would not be achieved,” they added.
Source: Journal of the American Dietetic Association
March 2009, Volume 109, Issue 3, Pages 497-501
“Increased Sweetened Beverage Intake Is Associated with Reduced Milk and Calcium Intake in 3- to 7-Year-Old Children at Multi-Item Laboratory Lunches”
Authors: K.L. Keller, J. Kirzner, A. Pietrobelli, M.-P. St-Onge, M.S. Faith