It's helpful to learn as much as possible about conditions like ADHD. However, sometimes learning more information requires being careful about what the information actually means.
A recent study found that kids with attention deficit-hyperactivity disorder were breastfed a shorter amount of time than other kids.
Yet, this study does not mean breastfeeding a child less will cause the child to develop ADHD. In fact, it may be that kids with ADHD end up breastfeeding for a shorter time on their own.
It's also important to understand what we do and don't know about the potential relationship between breastfeeding and ADHD. Which means more research is needed.
The study, led by Aviva Mimouni-Bloch, MD, of the Pediatric Neurology and Developmental Unit at Loewenstein Rehabilitation Hospital in Israel, looked at breastfeeding rates among children who did and did not have ADHD.
The researchers gathered data on 56 kids aged 6 to 12 who were diagnosed with ADHD between 2008 and 2009.
These children were compared to 51 unrelated children without ADHD and to 52 siblings of children with ADHD who did not have ADHD themselves.
The information gathered included the children's medical histories, how they were fed in their first year of life and basic demographic information, such as age, race/ethnicity and socioeconomic background.
All this information was gathered from the parents' thinking back on their children's early life, so the study results are only as reliable as the parents' collective memories of their children's early lives.
The researchers found that the children who had ADHD had been breastfed for shorter periods of time than the children in the other groups had been.
Among the children with ADHD, 43 percent had been breastfed at 3 months old, compared to 69 percent of the siblings group and 73 percent of the unrelated children without ADHD.
At 6 months old, 29 percent of the children with ADHD were breastfed, compared to 50 percent of the siblings and 57 percent of the unrelated children without ADHD.
At 1 year old, 13 percent of the children with ADHD were breastfed, compared to 25 percent of the siblings and 33 percent of the unrelated children without ADHD.
When the researchers looked at all the factors related to the children, they found four different factors were more likely among the children with ADHD.
Children with ADHD were less likely to have been breastfed at 3 months old, more likely to be male, more likely to have had parents who divorced and more likely to have an older mom.
For each additional year of a mother's age, the child was 10 percent more likely to be diagnosed with ADHD.
This study's findings, however, do not mean that breastfeeding does or does not cause ADHD or helps children avoid developing ADHD.
Glen Elliott, MD, PhD, a clinical professor at the Stanford University Department of Psychiatry and Behavioral Sciences and a dailyRx Contributing Expert, notes that making sense of these findings requires caution.
“This intriguing study emphasizes the care one must take in interpreting results," Dr. Elliott said. "The investigators found a strong association between ADHD and brief duration of breastfeeding as an infant. In much of the article, the implication is that the latter caused the former."
In other words, the authors suggest that the ADHD may have been prevented in some children if they had been breastfed longer — but it's not that simple. Dr. Elliott notes that cause and effect is difficult to identify.
"As the authors clearly explain in their discussion, even a strong correlation does not mean that brief or no breastfeeding increases the risk for ADHD," Dr. Elliott said. "Or, as physicians must remind themselves repeatedly, 'correlation does not mean causation.'"
He notes that any relationship could even go in the opposite direction.
"For example, it may be that infants with ADHD are more difficult to breastfeed, so quit sooner," Dr. Elliott said. "Or the two may have nothing to do with each other, with the correlation arising from some other set of factors altogether.
The authors also suggested that any possible causation could go the other direction: "Indeed, a shorter duration of breastfeeding in the ADHD group might be the result, rather than the cause, of ADHD," the authors wrote.
"Whether feeding behavior at the breast of a child who is about to develop ADHD leads to premature weaning is an important question that our retrospective, uncontrolled design cannot answer," they wrote.
What all this means is that the amount of breastfeeding a child receives may not necessarily cause or prevent a child from developing ADHD.
Parents may still choose to breastfeed for as long as possible for the other benefits until this relationship is better understood.
"Still, lots of evidence supports the value of breastfeeding, and perhaps someday this may be yet another reason for encouraging the practice," Dr. Elliott said.
The study was published online April 6 in Breastfeeding Medicine. No information was provided regarding funding. The authors declared no conflicts of interest.