Campaigns for a healthy lifestyle should target children and teenagers too. Focussing on the middle-aged alone on weight loss and cholesterol issues might not be adequate, warn Australian experts.
Scientists from the Menzies Research Institute in Tasmania have published a nationwide study into the cholesterol levels of children as they grow over 20 years. Their objective was to examine the effect of lifestyle changes on the stability of blood lipid and lipoprotein levels from youth to adulthood.
The participants were 539 young adults who underwent measurement at baseline in 1985 when aged 9, 12, or 15 years and again at follow-up between 2004 and 2006.
Changes in adiposity, cardiorespiratory fitness, saturated fat intake, smoking, and socioeconomic position were measured.
The researchers found that substantial proportions of individuals with high-risk blood lipid and lipoprotein levels at baseline no longer had high-risk levels at follow-up.
Of the participants who had high-risk levels in youth, those with greater increases in adiposity or who commenced or continued smoking were more likely to maintain high-risk blood lipid and lipoprotein levels.
Participants who became high risk at follow-up had greater increases in adiposity, were less likely to improve their socioeconomic position, and tended to become less fit between surveys compared with those who maintained normal-risk levels.
These effects tended to remain after adjustment for all predictive lifestyle variables.
Alison Venn of the Menzies Institute said, "The building up of fatty deposits in the arteries, we've known for a long time that that process starts very early in life.
"But what this study really helps confirm is that even for those children who are showing early signs of risk for heart disease that improving their lifestyle - maintaining a healthy weight, giving up smoking and so on - that those things really make a difference."
Researcher Costan Magnussen found that even children with the risk factors for heart attacks were able to improve their health as they grew older. The research also revealed children from poorer backgrounds were less likely to become healthy adults. Said Venn, "Even when you take into account some of those obvious things like diet quality and smoking and so on, there still seem to be some effect of social circumstances independent of those lifestyle habits and it's really not clear what that is."
The study, published in the Archives of Paediatrics and Adolescent Medicine, has gained attention in the United States, where doctors are considering testing children's cholesterol.