My friend’s twins both developed a stutter around first and second grade. This is isn’t an uncommon development for twins and it can be quite easily treated with speech therapy. My cousin’s children both received speech therapy at their school during third grade and neither stuttered again after that year. Not every child is as lucky however, and some children never quite recover from their childhood stutter. Another factor at hand could have been that my friend breastfed for at least six months, which can help children recover from stuttering more quickly than children who were not breastfed or were breastfed for a period shorter than six months.

A new study conducted by doctoral student Jamie Mahurin-Smith at the University of Illinois at Urbana-Champaign found that children who stutter can often recover more easily when they have been breastfed for at least the minimum time of six months to a year. "Long-chain fatty acids in human milk play an important role in the development of neural tissue," says Mahurin-Smith.

The study used 47 children who had suffered from stuttering at an early age. After examining their breastfeeding history, it was found that more children were able to recover and return to fluent speech if they had been exclusively breastfed as infants. Also, boys were more likely to develop stutters and were also more likely to recover if they had been breastfed as an infant, and were even less likely to develop a stutter at all if they breastfed for over a year.

"We've known for years that both genetic and environmental factors contributed to stuttering, but our understanding of the specific environmental variables in play has been murky," Mahurin-Smith said. "These findings could improve our understanding of stuttering persistence and recovery."

Other studies have also shown a correlation between breastfeeding and language development. One study conducted in 1997 found that infants that have been breastfed for over nine months were much less likely to develop language impairments than babies who were breastfed for a shorter period of time and had a better chance of producing variegated babbling earlier, which is an indicator of healthy language development.

These developments have usually been attributed to the fatty acids found in breast milk, but not in formula. It’s specifically docosahexaenoic acid and arachidonic acid (DHA) that play such a key role in neural issue development and Mahurin-Smith hypothesizes that early influences or delays in neurodevelopment could cause difficulties with speech fluency later in life.

DHA is the fatty acid that is most predominant in the brains of mammals, and babies who are lacking enough DHA has synthesize it from other fatty acids and incorporated into the brain, but not at the most efficient speed. This can lead to impairments in the brain structure and may be responsible for speech impairments like stuttering.

Source: University of Illinois at Urbana-Champaign (2013, August 5). Breastfeeding may protect against persistent stuttering. ScienceDaily.