On Quitting Hitting: why it's time to stop spanking our kids

One thing about discipline is, it’s a pretty personal thing. We parents usually have deep-rooted beliefs all tangled up with our own childhood experiences, culture, and religion. Spanking in particular is probably the most controversial method, and the one that parents have the strongest feelings about.

Even though spanking isn’t something that most parents talk about socially, it’s quite prevalent. A 2011 survey of all fifty states found that 72 percent of people think that spanking is okay, while twenty-three percent think it’s okay for a teacher to spank a child – which is still legal in 19 states by the way! (1)

In general, I’ve always felt that parents need to be given a wide berth to do what feels right for their family. I shy away from speaking in a heavy-handed or preachy way about parenting topics that are personal and emotional. Not every decision should be based only on research. In some of these areas, however, the science points so overwhelmingly in one direction that I have to say something. Vaccines are one of those areas. And now spanking is another.

Estimates of actual spanking vary widely, but it’s probably safe to say that at least half of parents do it. These parents are almost always trying to do what’s best for their child and to teach them certain values. They see an immediate benefit because an unwanted behavior usually stops right then and there when a child is spanked. They typically explain, “I was spanked when I was a kid and I turned out okay.”

The two things I would say to this are:

1. Did you though?

2. When we’re looking at whether an intervention is helpful or harmful, the experience of one person doesn’t mean much. But the effect on thousands of kids is quite meaningful and lets us draw powerful conclusions.

Fortunately, we have excellent data on the long-term effects of spanking. They’re not nearly as obvious as those immediate benefits, but they’re scary and something all parents should be aware of.

Perhaps the least surprising side effect of spanking is that it clearly increases aggressive behavior in kids. An excellent 2010 study looked at 2461 moms from twenty states enrolled in a big “cohort” at the birth of their children. (2) This let researchers follow the group for years to get all kinds of data. Moms were asked about spanking at age three and then about how aggressive their children were at age five. Kids who were spanked frequently (more than twice per month) had one-and-a-half times more aggressive behavior at age five.

There’s a big push in pediatrics to minimize “ACEs” (adverse childhood experiences) during early childhood. These can be thought of as toxic stresses that can actually change a child’s brain for the worse and cause problems that persist through adulthood. ACEs don’t only affect individuals, but they cause ripple effects in society as well. Some ACEs are obvious and extreme, such as neglect, sexual abuse, or being taken from your illegal immigrant parents and put in a cage.

But it’s been suggested that spanking should be considered an ACE as well since it has been associated with increased suicide attempts, moderate to heavy drinking, and the use of street drugs. (3) (No, this does not mean that it will happen to your child if you spank. But it does mean that it may be a bit more likely.)

Perhaps a less intuitive consequence of spanking is that it can decrease cognitive, or thinking, skills in kids. Several studies have found an association of spanking with decreased vocabulary skills during both the preschool (4) and elementary school (5) periods. That’s scary. No one knows for sure why this happens, but perhaps the stress of spanking actually changes how a child’s brain develops.  Perhaps we shift more of our brain cells to detect and avoid threats rather than learning big words.

Perhaps the scariest effect of spanking is that it literally can change how kids’ brains can look! A 2009 study found that kids who have undergone harsh spanking have significantly reduced gray matter in crucial parts of their brains, like the pre-frontal cortex. (6) This gray matter is pretty important stuff and more of it leads to higher IQ, better decision making skills, and the ability to learn self-control. These are some of the most important tools in navigating that tricky period between being a kid and an adult.

I realize this is all pretty depressing, but bear with me for one more. Kids who have been spanked also tend to have something called a “hostile attribution bias” as they grow up. (7) That’s a fancy way of saying that they expect the world to be mean to them. So if they are walking on the sidewalk, and someone accidentally bumps into them, they are more likely to think it was malicious. That’s a not a great way to go through life (especially when your ability to regulate your emotions has also been compromised). This seems to occur more frequently due to spanking by fathers.

This is only a small slice of the research on spanking. There is one thing glaringly absent from the data, however – any good evidence that spanking leads to long-term improvement in behavior or desirable qualities in adulthood. I also read quite a few opinion pieces on spanking from a more religious angle. While the authors mostly backtracked from spanking as a primary discipline technique, they seemed to agree that spanking was okay as long as it was “done with love.” That’s a tough one for me - I can’t imagine hitting a kid with love unless I was maybe trying to kill a wasp on their back.

Again, I generally tread lightly over parenting topics where emotion and personal beliefs run deep. But one of my responsibilities as a pediatrician is to comb through good research and identify things that help or hurt kids. Spanking hurts kids. The evidence is clear, regardless of our own religious beliefs or upbringing. It’s also a public health issue, because it leads to students and citizens who more aggressive, have higher rates of destructive behaviors, and have less control over their emotions.

I want to make it very clear that I’m not arguing against discipline for kids. It’s our job to teach them boundaries and to teach them to be accountable when they violate those boundaries (over and over and over again. . .). Fortunately, there are plenty of techniques such as timeouts, taking away privileges, and positive reinforcement that have been proven to improve behavior - all without leading to a future generation of slackers, softies, and snowflakes.

1. http://www.surveyusa.com/50StateDisciplineChild0805SortedbyTeacher.htm

2. Taylor CA et al. Mothers’ spanking of 3-year-old children and subsequent risk of children’s aggressive behavior. Pediatrics. 2010;125(5): e1057-e1065.

3. Afifi TO et al. Spanking and adult mental health impairment: the case for the designation of spanking as an adverse childhood experience. Child Abuse Negl. 2017 Sep;71:24-31.

4. MacKenzie MJ et al. Corporal punishment and child behavioral and cognitive outcomes through 5 years of age: evidence from a contemporary urban birth cohort study. Infant Child Dev. 2012;21(1):3–33.

5. MacKenzie MJ et al. Spanking and child development across the first decade of life. Pediatrics. 2013 Nov;132(5):e1118-e1125.

6. Tomoda A. Reduced prefrontal cortical gray matter volume in young adults exposed to harsh corporal punishment. Neuroimage. 2009 Aug;47(Suppl 2):T66-T71.

7. Nelson DA, Coyne SM. Children’s intent attributions and feelings of distress: associations with maternal and paternal parenting practices. Journal of Abnormal Child Psychology. 2009 Feb;37:223.