A new study has shown a link between the prevalence of ADHD and solar intensity (SI) in the US and nine countries abroad. Using three datasets (across 49 U.S. states and across 9 non-U.S. countries) a relationship between sunlight intensity and ADHD prevalence was found.

These results suggest that exposure to lots of sunshine has a preventative effect:  Sunshine may help to prevent ADHD.  

A big effect

This “Sunshine Effect” was not a small factor. It explained 34%–57% of the variance in ADHD prevalence.  This effect was not related to birth weight status, infant mortality, average income (socioeconomic status), latitude, or other factors which might have accounted for this effect.

It is also important to note that this effect was specific to ADHD. No similar “sunshine effect” was found for the prevalence of autism spectrum disorders or major depressive disorder.

The authors speculate that preventative effect of high sunshine intensity might be related to an improvement of daily sleep rhythms. Circadian clock disturbances have been associated with ADHD.

The take home message is clear

Clearly, more research is needed to confirm these initial findings.  If confirmed, these results have very important implications for understanding the causes of ADHD, and for how the difficulties associated with ADHD are handled by parents, schools, and the society more generally.

In my opinion though, we do not need to wait for further research to take action. There are many reasons to make sure that kids get out in the sun: to activate Vitamin D, to get exercise, which is good for your mood, your brain, and your body.  Being outdoors also is likely to get kids more in the flow of informal social activity which can help with social development.

So now there is one more reason to shut off the electronics and get your kids outside: it may help to prevent ADHD.

Didn’t your grandma say: “Get some fresh air and sunshine. Its good for you.”  How right she was.