Daniel Wolfram
This article was original written by colleague Ida-Marie Palm Varbæk for Welltica. https://welltica.com/could-your-birth-month-affect-how-long-you-live-here-is-what-the-data-shows/
Five studies agree: people born in the autumn tend to live longer than those born in spring.
Research spanning the US, Sweden, Denmark, Taiwan, and Austria found the same pattern between birth month and lifespan.
Tracking roughly 6 million Swedes, researchers discovered that people born in November carried the lowest premature adult mortality, while March births carried the higehst.
A separate analysis of 1,574 American centenarians also backed the claim. Those born between September and November had 37 to 47 percent higher odds of reaching age 100.
The findings are not new. In 2001, demographers Gabriele Doblhammer and James Vaupel concluded that autumn-born Austrians and Danes lived several months longer on average.
Why it matters when you are born
Researchers repeatedly argue that it all depends on when mothers are pregnant.
A mother pregnant through the darker winter months produces less vitamin D from sunlight, which may shape the immune system and cardiovascular development.
Seasonal infections are also a major factor. A fetus developing during flu or respiratory virus season may face immune signals that can be traced decades later.
Columbia University’s phenome-wide analysis of 1.75 million patient records identified 55 diseases with a statistical link to birth month. March births showed elevated cardiovascular risk, while October births carried a higher load of respiratory conditions.
