All were ranked from one to 10 based on their face and on their body, and completed a lengthy questionnaire about their self-esteem.
Doctoral student Tania Reynolds said women evaluated as less attractive were more motivated to diet and be thin if their husbands were attractive.
"The results reveal that having a physically attractive husband may have negative consequences for wives, especially if those wives are not particularly attractive," she said.
However, the extra motivation to stay fit and healthy didn't necessarily apply to women the researchers deemed to be more attractive than their husbands.
Men's motivation remained low regardless of how hot their partner was.
Co-author Andrea Meltzer, an Assistant Professor of Psychology, said the study clearly highlights the need to understand how a couple's relationship influences a woman's self-esteem.
"The research suggests there might be social factors playing a role in women's disordered eating," Ms Reynolds agreed.
"It might be helpful to identify women at risk of developing more extreme weight-loss behaviours, which have been linked to other forms of psychological distress, such as depression, anxiety, substance abuse and dissatisfaction with life."
She said the best way for men to boost their partner's self-esteem - and attractiveness - is to simply remind them they're beautiful.
