MUMS who breastfeed could be adding to their babies’ brainpower, according to a study by Durham University.
The study was carried out on 128 mammal species, including humans.
As a result, researchers discovered the longer the “maternal investment” – pregnancy and the period of breastfeeding – the larger the baby’s brain.
The fallow deer, which has about the same body weight as humans, is pregnant for seven months and suckles its young for six months.
It has a brain six times smaller than that of a human, who have nine-month pregnancies with suckling often lasting considerably longer.
Anthropologists from Durham’s Evolutionary Anthropology Research Group analysed statistical evidence on brain and body size and maternal investment in other mammals including gorillas, elephants and whales.
The study also shows that mothers-to-be with “higher metabolic rates” – which usually means that they eat well and spend energy by staying fit and active – are helping their babies to have a faster brain growth.
Michelle Swain, 33, from Barnes, Sunderland, who breastfed her two children, said: “I don’t know whether to believe this specific study, but I do believe that breast is best and can only be good for the future development of your baby.”
The study’s lead investigator was Professor Robert Barton from the university’s Department of Anthropology.
He said: “We already know that large-brained species develop slowly, mature later and have longer lifespans but what has not always been clear is why brains and life histories are related.
“One theory is that large brains increase lifespan by making the animal more generally flexible in its behavioural responses to unpredictable challenges, permitting slower life histories.
“However, our findings suggest that the slow-down in life histories is directly related to the costs rather than the benefits of growing a large brain.
“The necessary benefits to offset these costs could come in other ways, such as improving specific perceptual and cognitive abilities, rather than through some generalised flexibility.
“Our findings help us to understand what the implications are of evolutionary changes at different stages, before and after birth, but we now need to do more research to pinpoint exactly how changes to the pre and postnatal growth phases affect the brain structure.”