Study after study shows that married people eat better and are less likely to smoke and drink excessively. All of these healthy behaviours help explain why married people tend to live longer. However, men married to women tend to see additional longevity benefits than women married to men, for several possible reasons.

Sociological and psychological research historically suggests a "marriage gap" in benefits, often concluding that men tend to benefit more from marriage in terms of physical health and longevity. Studies frequently show that married men have lower rates of heart disease, better mental health outcomes, and longer lifespans compared to single men, often because wives traditionally take on the role of "health monitors," encouraging better diets and regular medical checkups. For women, the benefits are often more concentrated in financial stability and wealth accumulation, as married households generally have higher median incomes and more assets. however, the "benefit" is highly dependent on the quality of the union; women in low-quality or high-stress marriages often face worse health outcomes than their single counterparts. In modern times, as gender roles evolve and domestic labor becomes more balanced, the gap is narrowing, with both partners in healthy marriages reporting higher levels of overall life satisfaction and emotional support than those living alone.