New research suggests that breastfeeding exclusively for up to six months may help reduce the risk of attention-deficit/hyperactivity disorder (ADHD) symptoms in children later in childhood. The study, which analyzed data from over 37,000 families in Norway, found that the longer a child was breastfed exclusively, the lower their reported ADHD symptoms were at ages 3, 5, and 8.
ADHD is a common neurodevelopmental disorder affecting millions of children and adults. Symptoms can include inattention, hyperactivity, and impulsivity, interfering with daily life, school, and relationships. In children, these may manifest as frequent daydreaming, forgetfulness, fidgeting, difficulty following instructions, and challenges with social interaction.
The study's senior author, Berit Skretting Solberg, a psychiatrist and researcher at the University of Bergen, stated that while heredity is a significant risk factor for ADHD, other factors also play a role. "Our study suggests that the extent of breastfeeding may also help protect against the development of ADHD symptoms in young children," Solberg said in a press release.
Breast milk is rich in nutrients and compounds like long-chain fatty acids, amino acids, antibodies, and beneficial bacteria that support early development. The researchers found that the association between breastfeeding and lower ADHD symptoms was present in both boys and girls, with the strongest effects observed at ages 3 and 5. While any amount of breastfeeding showed some link, the effect increased with longer and more exclusive feeding, peaking at six months.
Scientists are exploring the reasons behind this connection, acknowledging that ADHD is typically caused by a combination of genetics, brain development, and environmental factors. Previous research has noted that mothers with ADHD sometimes breastfeed for shorter durations and are more likely to have children with ADHD symptoms. Conversely, children with ADHD traits can sometimes present breastfeeding challenges.
To isolate the potential effect of breastfeeding, the researchers accounted for genetic predispositions to ADHD, sociodemographic variables, and household influences through sibling comparisons. "Even after these adjustments, there was a clear but moderate protective effect of the duration of exclusive breastfeeding on later ADHD symptoms," Solberg noted.
However, the study authors cautioned that their findings are based on observational data and may not establish causality. The study population was also noted to be more educated and more likely to breastfeed for longer periods than the general Norwegian population. The researchers suggest the protective effect might be even more pronounced in populations with lower breastfeeding rates. Further research is recommended to fully understand the relationship between breastfeeding and ADHD.
In the United States, the Dietary Guidelines for Americans recommend exclusive breastfeeding for the first six months of life when feasible. While approximately 84% of new mothers in the U.S. initiate breastfeeding, the rate of exclusive breastfeeding drops significantly over time, with only about 27% continuing at six months postpartum.