Abraham Maslow proposed a hierarchy of needs. Foremost, primitive needs must be met (basic physiological, and sense of safety) before social needs can be met (e.g., intimacy). Subsequently, one can pursue more conceptual needs (e.g. morality and self-actualization).

Evidence suggests negative emotions can be damaging. In an article titled "The undoing effect of positive emotions", Barbara Fredrickson et al. hypothesized positive emotions undo the cardiovascular effects of negative emotions. When people experience stress, they show increased heart rate, higher blood sugar, immune suppression, and other adaptations optimized for immediate action. If unregulated, the prolonged physiological activation can lead to illness, coronary heart disease, and heightened mortality. Both lab and survey research substantiate that positive emotions help people under stress to return to a preferable, healthier physiological baseline.[119] Other research shows that improved mood is one of the various benefits of physical exercise.[118]