When flu season approaches, you may want to consider a new research-backed prescription to boost your immune system and live longer—and it might be closer to home than you think: People with strong social relationships have fewer health problems, are happier, and have increased longevity, researchers found.

People who have satisfying social connections with family, friends, and acquaintances are found to experience benefits just as important as those that come with a good night’s rest, a healthy diet, and a smoke-free environment, according to the Harvard Women’s Health Watch newsletter.

Researchers are exploring how biological and behavioral factors play into the benefits of social interaction. For example, caring behaviors are found to release stress-reducing hormones, which can affect the immune system, coronary arteries, gastrointestinal function, and insulin regulation.

But the quality of the relationships matter. In one study, disappointing and negative interactions with family and friends are tied to poorer health, and other research indicated that couples in marital turmoil experience signs of reduced immunity.

A lack of connections also is tied to depression, cognitive decline, and a mortality risk greater than obesity and physical inactivity. One study suggests that the absence of strong relationships increases the risk of premature death from all causes by 50 percent.

So, take time to foster meaningful relationships with those around you. Choose activities that are most likely to bring joy to you and the people you care about.

Delegate or discard tasks that eat into your time, or do them with family or friends. And if you can’t get together with everyone you’d like to see, make plans to visit them in the future. Show that you care, and you’ll be better positioned to ward off the flu and feel better all year long.