New Canadian research has found that children who drink whole milk are leaner than those who drink low-fat and skimmed versions.
The study, published this week in theAmerican Journal of Clinical Nutrition, also found that kids who consume whole milk have higher vitamin D levels.
Carried out by a team from St. Michael's Hospital in Toronto, the researchers looked at 2,745 children ages two to six years.
The team surveyed parents on milk consumption, measured the children's height and weight to calculate Body Mass Index (BMI), and took blood samples to assess vitamin D levels.
Of those surveyed 49 percent drank whole milk (with a 3.25 percent fat content), 35 percent drank two percent milk, 12 percent drank one percent milk and four percent drank skim milk. Less than one per cent of children drank some combination of the four types of milk.
The researchers found that the children who drank whole milk had a Body Mass Index score 0.72 units lower than those who drank 1 or 2 per cent milk, comparable to the difference between having a healthy weight and being overweight commented the study's lead author Dr. Jonathon Maguire.
In addition, children who drank one cup of whole milk each day had higher vitamin D levels, comparable to those who drank nearly 3 cups of one percent milk.
The team suggested that the higher vitamin D levels could be explained by the vitamin being fat soluble. As it dissolves in fat rather than water, milk with a higher fat content therefore contains more vitamin D.
There could be an inverse relationship between body fat and vitamin D stores, and as children's body fat increases, their vitamin D levels decrease.
Although the research didn't look at why there was a link between whole milk and lower BMI scores, Dr. Maguire suggested that because of its higher fat content children who drank whole milk felt fuller than those who drank the same amount of low-fat or skim milk. Children who don't feel full could be more likely to snack on other foods, which possibly are less healthy or higher in calories, and in the end consume more calories overall than those who drink whole milk.
Current guidelines from Health Canada, National Institutes of Health and American Academy of Pediatrics go against the findings from the study, recommending two servings of low fat (one percent or two percent) milk for children over the age of two to reduce the risk of childhood obesity, with Dr. Maguire commenting that the new research indicates a need to look again at existing nutritional guidelines.
Childhood obesity has tripled in North America in the past 30 years while consumption of whole milk has halved over the same period.