The friends you choose may be affecting your physical health

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People often say that you have to choose your friends well, and now there is scientific evidence that doing so can help people’s physical health

According to a new psychological study by researchers at the University of Auckland, people with positive experiences in their personal relationships appear to be in better physical health.

Previous research has focused on how conflict or relationship satisfaction can influence stress levels and blood pressure. In this study, however, the researchers looked at how any type of relationship, good or bad, affects a person’s health on a day-to-day basis.

New research published in Social Psychological and Personality Science examines the effects of positive and negative relationship experiences on the body, as well as how these experiences and health outcomes change from day to day.

“Both positive and negative experiences in our relationships contribute to our daily stress, coping and physiology, such as blood pressure and heart rate reactivity,” says lead author Brian Don, from the University of Auckland. “Also, it doesn’t just matter how we feel about our relationships in general; the ups and downs are important too,” he adds.

The study application

For the study, over the course of three weeks, 4,005 participants completed daily check-ins via their smartphone or smartwatch, providing assessments of their blood pressure, heart rate, stress, coping. Every three days, the participants also shared reflections on their closest relationship, detailing their positive and negative experiences.

The results showed that, on average, people with more positive and less negative experiences had less stress, better coping skills, and less systolic blood pressure reactivity, which translated into better physiological functioning in daily life. In contrast, the variability—or daily ups and downs—of negative relationship experiences, such as conflict, particularly predicted outcomes such as stress, coping, and overall systolic blood pressure.