Blood may be thicker than water, but water is still pretty damn essential to our health and well-being. In fact, in comparing the health benefits of our friendships vs. family relationships, research reveals that friends actually improve our physical and mental health far more than family members.

William Chopik, a Michigan State University assistant professor of psychology, conducted two separate studies involving nearly 280,000 people [1], and both studies concluded the same thing: "Friendships predict day-to-day happiness more and ultimately how long we'll live, more so than spousal and family relationships."

Friends literally boost our health and longevity.

Chopik is not the first to discover the health benefits of friends — especially for older folks. One study that followed nearly 1,500 older people for 10 years revealed that those who had a large network of friends were 22 percent less likely to die during the 10 years. WebMD expounded [2]:

"Close relationships with children and relatives, in contrast, had almost no effect on longevity. Lynne C. Giles, one of the researchers who conducted the study, emphasized that family ties are important, they just seem to have little effect on survival."

In addition to living longer, those who enjoy strong social support from friends also have fewer immune problems or cardiovascular issues and lower levels of the stress hormone cortisol.

Family can be great, but can also come with D-R-A-M-A.

Of course, family bonds can be beneficial, but they can also be fraught with deep-seated negative feelings like resentment, shame, and distrust. Dealing with the pressures and stresses of familial relationships can exacerbate existing health conditions or lead to new ones, like high blood-pressure, anxiety, poor sleep, and more. Lacking support from friends worsens things even more. Associate professor of psychology at Brigham Young University Julianne Holt-Lunstad claimed that [3] "as one's social network gets smaller, one's risk for mortality increases," in fact posing a risk factor almost as high as that of regular cigarette smoking.

Friendship is optional, not obligatory.

Let's face it: some family members are seriously stressful to be around, but you put up with them because, well, "they're family!" According to Chopik, the optional nature of friendships means that we're free to curate the company we keep, thus we don't have to endure nearly as much stress-inducing BS. We can choose the people who are supportive and healthy to be around and weed out the ones that aren't. Basically, we can have a no-haters rule for friends, and we don't always have that option with family.

Bottom line: keep investing in good friends.

Not unlike financial investments that compound interest over time, investing in friendships can only compound your good health and general satisfaction over time. As Chopik puts it, "Keeping a few really good friends around can make a world of difference for our health and well-being. So it's smart to invest in the friendships that make you happiest."