A recent study was reported as finding that switching to skim milk won’t prevent obesity among toddlers. These results are surprising, as health care providers (including dietitians) suggest consumption of low-fat milk after 2-years-of-age.
A closer look at the actual study left me questioning this reporting. The first thing that puzzled me was the grouping of milk-types. “Low-fat” milk included skim and 0.1%, while “high-fat” milk included 2% and whole. It was always my understanding that low-fat milk encompassed 2% milk. This grouping also meant that very few children were included in the low-fat milk group (only 14% at the initial 2-year assessment and 19% at the 4-year follow-up). The researchers stated that the low-fat milk drinkers had “higher odds” of being overweight or obese but did not state precisely what these odds were. I wish that I had the ability and the tools to determine if the findings would change if the 2% milk drinkers were incorporated into the low-fat milk group. I suspect that the odds of overweight and obesity might be different then.
Another major drawback of this study (which the researchers mention) is that they don’t examine the rest of the diet. That’s right, all they assessed was beverage consumption (milk, juice, and sugar-sweetened beverages… oddly, no mention of water). Without knowledge of the rest of the food that children were consuming, there is no way we can say with any certainty that consuming low-fat milk contributes to overweight and obesity.
Beverage consumption was also reported by the parents, not observed. Thus, there could have been inaccuracies in the reporting which contributed to the findings. It wouldn’t surprise me one bit if parents of overweight children were concerned about being judged and fudged the beverage consumption they reported to make themselves appear in a more positive light for providing their children with low-fat milk, and possibly, fewer sugar-sweetened beverages. Of course, this is just speculation. However, there are many reasons why self-reports of behaviours may be inaccurate and a number of those reasons may confound the results.
While these findings seem to contradict the widespread belief that low-fat milk is healthier for children than full-fat milk, as you can see there are a number of reasons why these results may also be meaningless. Don’t switch your child from 1% to full-fat milk on the basis of reports such as this. The whole diet and lifestyle is far more important in determining your child’s weight and health than the type of milk consumed.