How season of birth affects health and aging

We investigate how the season of birth affects human health and aging. For this purpose, we use five waves of the Survey of Health, Aging, and Retirement in Europe (SHARE) dataset and construct a health deficit index for 21 European countries. Results from log-linear regressions suggest that, on average, elderly European men age faster when they were born in spring and summer (compared to autumn). At given age, they have developed about 3.5 percent more health deficits. The bulk of the season effect is neither mediated through body height nor through education. In a subsample of Southern European countries, where the seasonal variation of sunlight is smaller, the season of birth plays an insignificant role for health in old age. In a subsample of Northern countries, in contrast, the season or birth effect gets larger. At given age, elderly Northern European men born in spring have developed on average 8.7 percent more health deficits than those born in autumn. In non-linear regression we find that the season effect increases with age suggesting that the speed of aging is also influenced by the season of birth.