Those surrounded by loved ones live longer.

One large-scale study of people 65 and older found that over a five-year period, those with no social ties were two to three times more likely to die than people with close bonds with friends, family or community organizations.

People who have tied the knot are healthier.

A 2004 study by the Centers for Disease Control showed that married couples live longer and have fewer cases of heart disease, back pain, headaches and serious psychological distress. Plus, they’re 50 percent less likely to be smokers. Married women are also 20 percent less likely to die of heart disease, suicide and cirrhosis of the liver when compared with single women, according to a Harvard study.

Married couples are more financially secure than singles.

By the time they’re close to retirement, married people have well over twice as much in assets as singles, note Linda J. Waite and Maggie Gallagher in The Case for Marriage.

Women who have had kids reduce their risk for some cancers.

Each birth reduces a woman's risk of developing breast cancer by 7 percent, according to a study published in The Lancet. Additionally, the more times
a woman has given birth, the less likely she is to develop ovarian cancer, says the American Cancer Society.

Puppy love pays off in better heart health.

A 2006 study found that dog owners in Victoria, British Columbia, got almost twice as much daily exercise as people who didn’t own canines. Research published in the British Journal of Health Psychology also suggested that dog owners have lower blood pressure and cholesterol, and suffer from fewer serious medical problems.