Babies born weighing less than 5.5 pounds at birth are more likely to drop out of high school, earn less as adults and age more rapidly, according to a new study.

The study, funded by the National Institute on Aging, analyzes 35 years of data on more than 12,000 individuals from the Panel Study of Income Dynamics, conducted since 1968 by the University of Michigan Institute for Social Research (ISR).

It found that babies with low birth weights are one-third more likely to drop out of high school; earn an average of 15 percent less as adults; and are burdened in their 30s and 40s with the health of someone that is 12 years older.

The study's authors, Robert Schoeni of the University of Michigan and Rucker Johnson of the University of California at Berkley, concluded that low birth weight babies born to families of all income sectors were at risk for lower success and health problems in adulthood.

However, the problem was more pronounced in lower income families without health insurance, Schoeni told Foxnews.com

He said researchers were able to conclude that the problem stemmed from low birth weight, rather than socioeconomic conditions by studying siblings.

"We looked at brothers, for example, raised in the same family with parents of the same economic and educational backgrounds and we think it's a low birth weight problem," he said.

The study also showed that increasing the income of the nation’s poorest families by just $10,000 lowers the probability of low-weight birth by 2.18 percent. This did not have the same effect among lower middle income and high-income families, however.

The study does not make recommendations on how to address the problem, but Schoeni said early intervention, both medically and educationally, during the formative years of childhood appears to help low birth weight children live more productive lives.

"There's a critical need to invest in those years because not only does it seem to have benefits in short run, but also in the long run," he said. "The investment can result in a reduction in poverty and negative labor outcomes, as well as increases in future earnings and improved health."

Schoeni said he and other researchers are now studying how low birth weight effects adulthood diseases such as obesity and high blood pressure.

The study also found:

— Compared to their normal birth weight siblings, low birth-weight children are 30 percent less likely to be in excellent or very good health in childhood. They also score significantly lower on reading, passage comprehension, and math achievement tests.

— Weighing less than 5.5 pounds at birth increases the probability of being in fair or poor health as an adult by more than 70 percent.

— The earnings penalty for being born with low weight increases with age, with a 10 percent reduction in hourly wages from ages 18 to 26; a 10.2 percent reduction at age 25; a 15.6 percent reduction at age 35; and a 22 percent reduction in wages from ages 37 to 52.