Children born "small for gestational age" - that is, significantly smaller than most babies born after the same number of weeks of pregnancy - are prone to developing "visceral" adiposity (fatness) of the abdomen, even without being overweight, research hints.
Visceral fat, also known as organ fat, is packed in between internal organs, as opposed to subcutaneous fat that is found underneath the skin. "Visceral adiposity" is a term used to describe the fat that accumulates around the abdominal organs.
Small for gestational age, or SGA children, the researchers explain, show a "catch-up" effect in infancy and tend to become overweight by the age of six years. Weight control is advocated as a preventive measure in these children, but that may not be enough.
Dr. Lourdes Ibanez of the University of Barcelona, Spain, and colleagues came to this conclusion after studying 64 children aged six years - 32 born appropriate for gestational age, and 32 born SGA who subsequently showed catch-up growth.
"We found that even in the absence of obesity and with a perfect matching for body mass index, six-year-old children born SGA had more visceral fat than children of the same age born appropriate for gestational age," Ibanez told Reuters Health.
SGA children had a total lean mass, total fat mass and blood levels of the appetite-regulating hormone leptin comparable to those in the control group.
However, SGA children had significantly higher insulin levels and significantly higher levels of a hormone linked to growth and development called IGF-1. SGA children also showed a "striking shift from abdominally subcutaneous to visceral fat."
While these results need to be confirmed in other populations and follow-up is required, they suggest that "preventing obesity may be not enough to prevent the development of a situation reminiscent of the metabolic syndrome in SGAs," Ibanez noted.