FRIDAY, April 20 (HealthDay News) -- Adults who were obese as children are at increased risk for liver cancer, a new study suggests.

Researchers looked at the birth weight and body-mass index (a measurement of body fat based on height and weight commonly called BMI) of more than 165,000 men and 160,000 women in Denmark born between 1930 and 1989.

Of those participants, 252 developed hepatocellular carcinoma, the most common form of liver cancer in adulthood.

The study authors calculated that at age 7, the risk of developing hepatocellular carcinoma increased by 12 percent for every one-point increase in BMI. By age 13, that risk increased to 25 percent. Therefore, as units of BMI increased into adulthood, so did the risk of developing hepatocellular carcinoma. This was consistently similar across both genders and all ages.

Other factors associated with liver cancer include alcoholism, infection by hepatitis B and C, and other liver diseases. But the study results did not change when participants with these factors were removed from the study, which indicates that childhood obesity was the major factor in the development of hepatocellular carcinoma, the researchers said.

The study was slated for presentation Thursday at the International Liver Congress in Barcelona.

"Childhood obesity not only leads to the development of many adverse metabolic conditions -- such as type 2 diabetes and heart disease -- but also fatty liver disease, which may subsequently result in liver cancer," Dr. Frank Lammert, a scientific committee member of the European Association for the Study of the Liver, said in an association news release.

"The importance of maintaining a healthy childhood BMI cannot be underestimated," Lammert said in the release. "These alarming study results point to a potential correlation between childhood obesity and development of liver cancer in adulthood."

Data and conclusions presented at meetings should be considered preliminary until published in a peer-reviewed medical journal.

More information

The American Liver Foundation has more about liver cancer.