In this systematic
and meta-analytic review, we examined the current evidence on positive
psychological variables between individuals who consumed meat and individuals
who abstained from meat consumption. After systematically searching five online
databases for primary research on positive psychological outcomes in meat
consumers and meat abstainers, 19 studies with 94,204 participants (nmeat
consumers = 82,449, nmeat abstainers = 9,964) met
the inclusion/exclusion criteria. The primary outcomes were self-esteem,
satisfaction with life, and positive mental health. The secondary outcomes were
positive affect, psychological well-being, vigor, optimism, happiness, and
meaning in life. Individuals who consumed meat had greater positive mental
health (g = 0.21, 95% CI [0.08, 0.31], p = .001) than meat
abstainers. No significant differences were found between the groups on
self-esteem (g = 0.19, 95% CI [-0.01, 0.38], p = .06) and
satisfaction with life (g = 0.02, 95% CI [-0.04, 0.07], p = .57).
The majority of studies examining the secondary outcomes showed no group
differences. The evidence was limited, requiring more studies to determine the
role of study quality in diet-health relations. Study designs precluded
inference of causal and temporal relations. With respect to clinical practice,
our findings add to the current controversial diet-health debate.
