Researchers have found an association between when mothers wean their babies and type 1 diabetes risk.
US scientists discovered that introducing babies to solid food both early and late was linked to an increased chance of being diagnosed with the autoimmune disease.
Exposing infants who are less than four months of age to solid food doubles the risk, while weaning at six months or older triples the risk.
The findings contradict NHS guidelines, which recommend weaning should begin when a baby is around six months old.
Scientists in Denver, Colorado, found a "safe window" between four and five months, the ideal time to start consuming solid food.
About 300,000 people in Britain have type 1 diabetes, which is when the body's own defence systems target cells in the pancreas that create insulin. The disease usually takes hold of the body during childhood.
Researchers pinpointed nearly 2,000 infants with a greater genetic vulnerability to type 1 diabetes and followed their progress, with their diet monitored. In all, 53 developed the disease.
The authors, headed by Brittni Frederiksen, from the University of Colorado, wrote in the
journal JAMA Pediatrics : "Our data suggest that there is a complex relationship between the timing and type of infant food exposures and T1DM (type 1 diabetes mellitus) risk.
"In summary, there appears to be a safe window in which to introduce solid foods between four and five months of age; solid foods should be introduced while continuing to breastfeed to minimise T1DM risk in genetically susceptible children."
Copyright Press Association 2013