People who had low birth weights and those breastfed for short periods may be more likely to develop chronic inflammation linked to heart disease in adults, a study said Wednesday. Researchers in the United States found a “significant” association in almost 7,000 people between birth weight or duration of breastfeeding and higher levels of C-reactive protein (CRP), an indicator of inflammation, in blood samples of young adults. The protein is produced by the liver and levels increase when a person suffers from inflammation. “Each pound of additional birth weight predicted a CRP concentration that was five percent lower,” said a statement from Northwestern University, whose experts took part in the study published in the journal Proceedings of the Royal Society B.