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.