Overweight children could be eating their way into problems - no news there. But an increasing body of scientific literature suggests that obesity precedes the development of blood lipid disorders, such as abnormally high cholesterol, and that even in very young children, overweight or obesity can set off a cascade of early risk factors for cardiovascular disease.
A study published in a recent issue of the American Journal of Clinical Nutrition has found that normal-weight children may be hypercholesterolemic (abnormally high cholesterol), and that this condition predisposes young girls to the development of overweight and obesity later in childhood.
The Bogalusa Heart study, which examined the early natural history of cardiovascular disease in children and young adults, enrolled 58 children with hypercholesterolemia and 215 children with normal cholesterol levels when they were five to six years old, and followed them for the next six years.
The group was equally divided between girls and boys, and 41 per cent of the children were black. None of the children were obese at the start of the study.
The only difference between the two groups other than cholesterol levels was that the non-hypercholesterolemic children were significantly taller than the hypercholesterolemic children.
In the following years, the hypercholesterolemic girls' body mass indexes (BMI) increased at a greater rate than the non-hypercholesterolemic girls', and by age 11-12 years, 45.2 per cent of the hypercholesterolemic girls were overweight or obese, in comparison to 21.6 per cent of the non-hypercholesterolemic girls. This effect was independent of race. In the same age range for boys, BMIs were no different for hypercholesterolemic and non-hypercholesterolemic subjects.
Although the relationship between hypercholesterolemia and weight gain is unclear, the authors propose that abnormally high cholesterol may be a marker of an altered metabolism, which later results in excess adiposity. When the result is obesity, blood lipid disorders can become exacerbated, and blood pressure and insulin concentrations may increase.
Full findings are published in the American Journal of Clinical Nutrition, 2002;76:730-5.