Psychological and behavioral responses to genetic test results indicating increased risk of obesity: does the causal pathway from gene to obesity matter?.

BACKGROUND: Common obesity-associated genetic variants may exert their effects through increasing eating or decreasing metabolism. Such differences might influence individual responses to obesity genetic test results.
METHODS: This was an experimental analogue study: 191 participants were asked to imagine they had received a genetic test result indicating high eating-based (n = 37) or high metabolism-based (n = 41) risk of obesity, an enzyme test result indicating high eating-based (n = 35) or high metabolism-based (n = 41) risk of obesity, or no risk information (n = 37). Outcomes included perceived risk, self-efficacy (confidence in ability to eat healthily), response-efficacy (confidence that eating healthily will reduce risk), and intention to eat healthily.
RESULTS: The groups receiving increased obesity risk information reported greater perceived risk and intention to eat healthily than the no risk information group (both p < 0.01). There were main effects of test type on perceived risk (genetic vs. enzyme: 3.91 vs. 3.55, p = 0.031) and of causal pathway on worry (eating vs. metabolism: 3.33 vs. 2.86, p = 0.049), but no effects of either manipulation on any other outcomes.
CONCLUSION: Personal risk information indicating increased obesity risk may increase motivation to eat healthily, regardless of whether the risk is described as genetic or non-genetic or as acting through an eating-based or metabolism-based causal pathway.