Cutting Back on Fat Is Safe for Kids
He says that the unrestricted group had better cholesterol levels than expected, "which may have also accounted for the lack of difference at the last follow-up." Tershakovec, who was not involved in the study, is director of the Lipid-Heart Clinic at Children's Hospital of Philadelphia.
Obarzanek points out that going through puberty causes a natural decline in LDL levels. And the small increase at the end of the study may have been due to the adolescents entering adulthood.
The average age at the end of the seven years was 17, she says, and this is the beginning of their LDL level approaching adulthood levels. "We know that adult levels of LDL levels are higher than children's, so there will be a natural rise no matter what we do.
"But the idea is to make the rise a little bit smaller than what it would have been ordinarily," she says.
High-density lipoprotein or HDL cholesterol, the "good" cholesterol, remained similar between the two groups throughout the study. The lower-fat diet did not appear to affect its levels.
However, Gregory Miller, PhD, who is vice chairman of nutrition research at the National Dairy Council in Rosemont, Ill., is concerned about how these study results can be applied to real life.
"They say that it's safe to put kids on a low-fat diet when they're closely followed by pediatricians and nutritionists and are getting a lot of dietary advice on a regular basis," he says, "But this might not work in the real world.
"The children [in the study] were in a very controlled environment," Miller says, "But the reality is that in the real world, where people aren't nutritionists and they're not getting a lot of intervention from a dietician or nutritionist, they may not interpret [a reduced-fat diet] correctly." Miller was not involved in the study.
Tershakovec feels that the fear is unwarranted. He points out that there have been cases in scientific literature where reduced-fat diets caused problems in children, but it generally occurred when the family had gone overboard in restricting fat.
"One message that's important to get across," he says, "is that people who got into trouble are those who gave their child a diet that was inappropriately restrictive. They cut down too much on calories, nutrients, everything -- in addition to fat."
Obarzanek agrees. "There were cases where people just got overzealous. The incidences where we saw problems were where parents were starving their kids, or maybe the kids were doing it to themselves. It was more a calorie reduction rather than just fat reduction."
Parents should get some guidance before they start reducing calories and fat in children, Tershakovec says. "But this study shows that you can make the changes safely in children. Along with promoting a lower-fat diet, the hope is that you'll also be promoting a healthy lifestyle."