Science Says Babies Born In These Months Tend To Be Healthier

If you happen to have a May birthday, you can breathe a (small) sigh of relief. Research shows that May babies have a slightly lower risk of getting certain diseases than their fall and winter counterparts. Scientists from Columbia University studied medical records from 1.7 million patients treated in New York between 1985 and 2013, and found a link between the development of certain diseases and the birth months of the patients (via Time). Skeptical? John Perry, a senior investigator scientist at the University of Cambridge, says, "It's not horoscopes or the alignment of planets" (via U.S. News & World Report). Researchers speculate that the mothers' greater exposure to sunlight during May, June, and July, and consequently higher vitamin D levels, may play an important role.

A British study of 450,000 births similarly found that summer babies generally had better health outcomes as adults. Ken Ong, programme leader at the Medical Research Council Epidemiology Unit, University of Cambridge, communicates in an email, "Children who were born in the summer were slightly heavier at birth, taller as adults, and went through puberty slightly later, relative to those born in winter months" (via Today).

Ong also emphasized that maternal health seems to play a significant role in these research results (via Today). Dr. Perry adds, ​​"It's hard to think the amount the mother goes out in the sun has an impact on a baby's health in two decades' time" — but that does seem to be the case (via U.S. News & World Report).

Researchers in both studies emphasize that, while the associations are real, a person's birth month still plays a minor role when it comes to the baby's overall health. Other factors, such as diet and lifestyle, are still much more influential. Nicholas Tatonetti, the senior author of the Columbia University study and an assistant professor at Columbia University Medical Center, adds, "It's important not to get overly nervous about these results because even though we found significant associations the overall disease risk is not that great. The risk related to birth month is relatively minor when compared to more influential variables like diet and exercise" (via Time).