For more than a century, sociologists have predicted a decline in faith. Measuring religious belief is very difficult, but what we do know is that Americans born after 1980 are less likely to identify with a religion than were members of any previous generation at the same age . It remains to be seen, though, whether their beliefs will change in adulthood: members of other generations have become more religious after marrying and having kids .
If Millennials do eventually become religious, they may reap some unexpected fringe benefits. For one thing, compared with the nonreligious, religious people report more satisfaction with their love lives  and sex lives . Frequent church attendance has also been associated with lower rates of smoking and drinking, a greater tendency to exercise , reduced risk of cancer, and improved cardiovascular health . A research review conducted on behalf of the National Institutes of Health went so far as to declare that “church/service attendance protects healthy people against death” .
So religion affects the course and even duration of your life. What about the converse: How does your life—specifically your early life—affect your religion? Over the decades, studies have identified a number of contributors to religiosity, many of them unsurprising—like attending religious services as a child . Family also matters a lot: studies have found that kids with married parents of the same faith are most likely to keep the faith they grew up with . Those with divorced parents, however, are less likely than their peers to affiliate with a religious institution (though they’re no less likely to feel “closeness to God”) . And kids of certain faiths, such as young Mormons, evangelicals, and Jews, are more likely to stay in the fold than are those of other denominations .