Milk & Calcium intake in Children

Children's Dairy Intake in the United States: Too Little, Too Fat?

Kranz S, Lin P, Wagstaff DA J Pediatr. 2007;151:642-646; Epub 2007 Jul 24

Kranz and colleagues note that the most bioavailable food form of calcium occurs in dairy products, thus most professional organizations and advisory boards recommend that children obtain their daily calcium goals through dairy intake. However, whole milk contains almost double the amount of calories per unit volume (3.5% milk fat) compared with nonfat milk (less than 0.5% milk fat) without any additional calcium.

This study sought to compare daily calcium intake by US children. The authors used data from the 1999-2002 National Health and Nutrition Examination Survey (NHANES) and compared them against recommendations of the US Department of Agriculture's MyPyramid plan. The authors note that the American Academy of Pediatrics' (AAP) recommendations for dietary calcium exceed those of MyPyramid.

NHANES data were provided by subjects in an interview. The dietary data used in this study involved 24-hour dietary recall. The study included over 7000 children with dietary intake data, along with physical examination parameters. The current USDA dietary goals are 2 cups of dairy per day for children 2-8 years and 3 cups per day for children older than 8.

Only the youngest age group, 2- to 3-year-olds, met the 2-cups-per-day recommendation on the basis of their average intake. Children 4-8 years fell just short of 2 cups per day, while children 9-18 took in under 2 cups per day, far short of the goal of 3 cups per day for children older than 8.

In general, younger children obtained the majority of their dairy intake (approximately two thirds) from milk, but milk intake accounted for only half of dairy intake in the oldest children. When looking at the fat content of milk consumed, it was evident that whole milk and reduced-fat milk (2% milk fat) comprised a large majority of intake: 87% for children 2-3 years and 78% for children 4-8 years.

Even older children took in high proportions, with whole or reduced-fat milk comprising approximately 75% of milk intake for children older than 8 years, although there was a relative decrease in whole-milk consumption relative to reduced-fat milk.

The authors concluded that dietary intake of calcium is insufficient for children 4-18 years in the United States, and that the dairy products consumed are often unnecessarily high in fat.

Viewpoint

It has taken barely a generation for milk to go from a "luxury" item in childhood diets to a potential "villain." Although the AAP recommends whole milk for children under 2 years old, we could clearly advocate that our patients should consume lower-fat varieties at older ages.^[1] The authors also highlight that there has been a decline in dairy intake during adolescence, when dietary calcium needs increase significantly compared with young childhood. In this study, adolescents in the 14- to 18-year range took approximately 38% of recommended calcium.

Among the many topics to discuss at adolescent visits, diet and calcium intake specifically should remain an important one.