Summer babies have a lot going against them. Forget having a sunny, happy birthday party — all their friends are out of town for summer vacation. And they're usually right at the cutoff date to start elementary school, so they end up as either the youngest or oldest kid in class. But it looks like summer babies get the last laugh, because a new study has found they might grow up to be healthier adults.
To see how birth month affected health later on, University of Cambridge researchers analyzed the health data of about 450,000 men and women from the U.K. Biobank study, which collects volunteers' health information across the country.
The results, published in the journal Heliyon, were fascinating. People born in the summer had a higher birth weight and were taller as adults than people born in any other season. Girls born in the summer also had their first period and started puberty later, which are indicators of better health as adults.
Why the differences? It could be all about sunshine. The seasons determine how much sunlight (think vitamin D) a fetus is exposed to in utero, and that can have a big effect on health. So summer babies are exposed to more vitamin D during the second trimester of pregnancy, which might translate into health benefits later on.
The researchers say that further research is needed to figure out exactly how vitamin D affects the fetus, so they're not about to recommend more vitamins for expecting moms. But in the meantime, people with summer birthdays can go ahead and gloat — they've earned it.