Weight gain by kids as young as 5 years old—and up through their teen years—can influence their health later in life, according to a recently released study spanning a quarter of a century.

Following kids and teens ages 5 to 19 years old (and up to 30 to 48 years old at the end of a follow-up segment), researchers found that risk factors for diabetes can begin in childhood, and that weight management is important even in those early years.

The first leg of the study was a multistage survey conducted between 1972 and 1978. The follow-up study was conducted between 2000 and 2004. The 814 boys and girls in the study were recruited from one school district in the Cincinnati area.

The main focus of the study, as described by the researchers, was to follow the risk for, and development and progression of, the metabolic syndrome. The researchers aimed to use the data from the two studies to draw a correlation between metabolic syndrome in childhood and in adulthood. They classified kids as having pediatric metabolic syndrome if they exhibited three or more of the following factors:

• A body mass index (BMI) over the 90th percentile
• A large waist
• High blood glucose levels
• Low HDL cholesterol (the “good” cholesterol)
• High triglycerides
• High blood pressure

At the study’s start, 18.2 percent of the students were at risk for overweight and 7 percent were already overweight. Thirty-two of them had pediatric metabolic syndrome.

The prevalence of metabolic syndrome in this group rose from 3.9 percent in the initial study to 26.6 percent in the follow-up study. Nearly half of the 814 adults had a large waist circumference (described as 88 cm or more for females and 102 cm or more for males).

Adult BMI was strongly associated with pediatric BMI. Of the kids who were at risk for becoming overweight, 63 percent were determined obese in the follow-up study.

In addition to pediatric metabolic syndrome, the other factors with the biggest impact on the development of type 2 diabetes in adulthood included age, race, and parental history of diabetes. Black men and women had twice the risk of developing type 2 diabetes as whites did.

Researchers concluded that early weight management is key. The correlation between the increase in BMI and the increased risk of metabolic syndrome demonstrates the link between weight and metabolic syndrome, obesity, and type 2 diabetes later in life. Weight management in early and middle adult years likely plays a significant role in warding off type 2 diabetes and metabolic syndrome, according to the researchers.

This study was published online Nov. 5, 2007, in The Journal of Pediatrics.