While having an unhealthy lifestyle as a child can make it difficult to be fit as an adult, it doesn't destine you to a lifetime of disorders, according to a new study.

Even youngsters at high risk of developing high cholesterol levels were able to improve their levels through their lifestyle choices as they grew into adulthood, researchers found.

The researchers, who measured the cholesterol levels of 539 youths and then remeasured them 20 years later, also found that the people at risk for high cholesterol in both childhood and adulthood were the most ones likely to have smoked and gained more body fat over that 20-year period.

The results suggest that weight gain and lifestyle choices such as smoking "have the potential to shift" young people from having a high risk to a low risk of developing high cholesterol levels, the researchers from the University of Tasmania in Australia and the University of Turku in Finland concluded.

The researchers recorded the cholesterol readings when the participants were 9, 12 or 15 years old, and again 20 years later between 2004 and 2006.

Of the 539 participants, 12 percent were found to have low levels of the "good" cholesterol as adults, an indicator of poor health. But among those who had not improved their lifestyle factors since youth, that rate was 26 percent.

Among adults with high cholesterol, those who initially hadn't seemed to be at risk for developing the condition were more likely to have increased body fat and be less fit than those who had remained in the low-risk group as they aged.

The researchers defined being "high-risk" as having a total cholesterol level of at least 240 milligrams per deciliter; a "bad" cholesterol level of 160 milligrams per deciliter or higher, and a "good" cholesterol level of less than 40 milligrams per deciliter. The study participants' height, weight, waist circumference, skin-fold thickness, smoking behaviors, cardiorespiratory fitness and socioeconomic factors were also recorded at the beginning and end of the study.

"Good" high-density-lipoprotein (HDL) cholesterol helps guard against heart attacks and slows arterial plaque buildup, whereas "bad," low-density-lipoprotein (LDL) cholesterol narrows and hardens the inner walls of arteries, increasing the risk of heart attack, according to the American Heart Association.

The findings "emphasize that preventive programs aimed at those who do not have high-risk blood lipid and lipoprotein levels in youth are equally important if the proportion of adults with high-risk levels is to be reduced," the researchers said.

Pass it on: Even if you are at risk for high cholesterol as a kid, you can decrease your risk into adulthood by losing weight and stopping smoking.

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