Lengthy commutes aren't just a daily annoyance -- they can do real damage to your relationship.

Researchers at Sweden's Umea University sifted through the records of two million households and found that when one partner commutes for longer than 45 minutes each day, the couple is 40% more likely to divorce.

They also concluded that the risk is highest in the first few years of long commuting but decreases after five years, because most families will have adapted by then.

It's yet another finding in a long line of studies exposing the wide range of problems long commuters face. A set of research reports over the past decade compiled by Slate paint an eerie picture for the 3.5 million long-distance commuters in the country.

Here's what Slate dug up:

40% of those who commute more than 90 minutes (each way) every day experience worry, compared to 28% of those with extremely short commutes, according to last year's Gallup-Healthways Well-Being Index.

The Gallup survey also noted that one in every three commuters that spend 90 minutes or more traveling home every day experience recurrent physical pain.

Long commutes increase the chance that we make fast food purchases, according to a study from Brown University, and researchers at UCLA and Cal State-Long Beach found that vehicle mileage has a stronger correlation with obesity than any other lifestyle factor.