Treat “regular social contact” as a health expense — don’t wait until you’re feeling down to reach out. Infrequent social contact is linked to higher mortality, but causality remains unclear.

It requires some money and time to arrange meetups. The hard part is making the effort to schedule them even when you’re in a good mood.

A meta-analysis pooled 70 prospective studies with 3.4 million participants and mean follow-up of 7 years. Social isolation, loneliness and living alone were associated with higher mortality. After adjustment for confounders such as age and health, weighted mean odds ratios were 1.29, 1.26 and 1.32, respectively. The effect sizes were similar and larger below age 65 than in older adults.

Holt-Lunstad J, Smith TB, Baker M, Harris T, Stephenson D (2015). Loneliness and social isolation as risk factors for mortality: a meta-analytic review. Perspectives on Psychological Science, 10(2), 227-237. https://doi.org/10.1177/1745691614568352

This topic remains debated. These findings are purely correlational; no randomized controlled trials have been conducted to prove cause and effect. It’s also true that people with poorer health are more likely to become isolated or have fewer social interactions. The authors argue that social relationships are as important to health as smoking or obesity, yet there’s no randomized evidence showing that increasing social contact actually lowers mortality. This point does not contradict Section 3’s advice to “cut back on draining relationships”; that section focuses on eliminating toxic connections, while this one stresses the value of maintaining those that replenish your energy.