NEW YORK - The chicken nuggets are coming home to roost. By the time today's teens are middle age, the rate of heart disease could be 16 per cent higher because of the extra pounds they are carrying around today, a U.S. study suggests.
A second study, by Danish researchers, documents a connection between excess weight in even younger kids and heart disease in adults -- especially boys.
The two reports in Thursday's New England Journal of Medicine may well be underestimating the future health effects of childhood obesity, said Dr. David Ludwig, director of an obesity program at Children's Hospital Boston.
"We've simply never had a generation that's been this heavy from so early in life. The consequences of that are unprecedented and unknown," said Ludwig, who was not involved in the research.
While the U.S. projections were based on a computer model, the Danish study is a large, decades-long look at what happened in real life to 277,000 children as they grew up. Some 14,500 of them -- twice as many men as women -- had heart disease or died from it before age 60.
The researchers found that the more overweight a child was between ages 7 and 13, the greater the risk of heart disease was in adulthood. The relationship was strongest in boys and increased with age.
For example, an average-size 13-year-old boy had a 12 per cent risk. But for a boy of the same age and height who weighed about 25 pounds more, the risk went up by one-third, to 16 per cent.
"Our findings suggest that as children are becoming heavier worldwide, greater numbers of them are at risk of having a (coronary heart disease) event in adulthood," said the researchers from the Institute of Preventive Medicine in Copenhagen.
Today, about a third of U.S. youngsters are either overweight or obese. Increasing numbers of obese children are being diagnosed with type 2 diabetes, high blood pressure, bad cholesterol and other obesity complications that were seldom seen in children before.
Some of those complications are risk factors for heart disease, which could explain the link between childhood weight and a higher risk of heart disease, the Danish researchers suggest. Or it could be because many heavy children -- although not all -- become heavy adults, they said.
Their study used detailed health records kept for every schoolchild in Denmark. They calculated the body mass index, which is based on height and weight, for children born between 1930 and 1976. Using hospital discharge records and a death registry, they tracked the children from age 25 to find out who had heart disease by age 60.
One of the researchers, Jennifer Baker, said previous studies that have looked at the issue have been inconsistent, and this is the "first to convincingly demonstrate that excess weight in childhood is associated with heart disease in adulthood."
The U.S. researchers used obesity figures for U.S. teens in 2000 to estimate that as many as 37 per cent of men would be obese when they reached 35, compared to 25 per cent now. For women, as many as 44 per cent would be obese; now the rate is 32 per cent.
Using a computer model, they estimated that by the time the teens are 50, the rate of heart disease will rise 5 per cent to 16 per cent -- as many as 100,000 extra cases. They also projected heart disease deaths could rise by as much as 19 per cent.
"If we do nothing, the health consequences are really going to be quite dramatic," said Dr. Kirsten Bibbins-Domingo, of the University of California, San Francisco, lead author of the study.
Projections of increasing rates of heart disease and deaths between ages 35 and 50 were particularly striking, she said.
"This is an age when people are normally working, they're raising their families. They're not worried about going to the doctor or worried about dying or having a heart attack," said Bibbins-Domingo.
The researchers noted that their predictions are based on current treatments and trends for obesity and heart disease, and changes in prevention and treatment could make a difference.
