Using census data for more than 1 million people in Austria, Denmark and Australia, scientists at the Max Planck Institute for Demographic Research in the northern German town of Rostock found the month of birth was related to life expectancy over the age of 50.

Seasonal differences in what mothers ate during pregnancy and infections occurring at different times of the year could both have an impact on the health of a newborn baby and could influence its life expectancy.

Babies born in the autumn weighed more than those born at springtime. In later life, low birth weight was associated with increased blood pressure, cholesterol levels, some forms of obesity and a decrease in lung function.

In Austria, adults born in autumn (October-December) lived about seven months longer than those born in spring (April-June), and in Denmark adults with birthdays in autumn outlived those born in spring by about four months.

In the southern hemisphere, the picture was similar. Adults born in the Australian autumn -- the European spring -- lived about four months longer than those born in the Australian spring.

The study focused on people born at the beginning of the 20th century, using death certificates and census data. Although nutrition at all times of the year has improved since then, the seasonal pattern persists, Doblhammer said.

In a separate study, Doblhammer analyzed the birth weight of about 3,000 twins born in the United States in the 1970s and 1980s and found that those born in spring and summer weighed less than those born in autumn.

Dr. Mercola's Comments:

When I first examined this study, it was clear to me that there was a foundational connection to sun exposure and vitamin D metabolism, so I asked Krispin Sullivan, (one of the leading experts in vitamin D) for her insights, which she shares below. Krispin will be publishing her book "Naked at Noon" on the benefits of vitamin D early next year. Her site has more information on this topic. Optimal levels of vitamin D in the mother seem to regulate D binding proteins and D receptors in the newborn (contributing to stronger bones and better tooth enamel as well as extended life span). It will be in the chapter on fertility, pregnancy and childbirth in Dr. Krispin's book. The effects of D deficiency during pregnancy on the offspring cannot be made up later with D supplements. Related Articles: Vitamin D Is Not A Vitamin But A Steroid Hormone Precursor Breakthrough Updates You Need to Know on Vitamin D Test Values and Treatment for Vitamin D Deficiency