Title

Sex and Age-Related Differences in Perceived, Desired and Measured Percent Body Fat Among Adults

Document Type

Article - Merrimack Access Only

Publication Title

Journal of Human Nutrition and Dietetics

Publisher

The British Dietetic Association Ltd.

Publication Date

10-2015

Abstract/ Summary

Background: Body image distortion/discrepancy leads to psychological stress, disordered eating and mental and physical disease. To begin to assess body image distortion/discrepancy, we compared perceived, desired and measured percentage body fat in male versus female and college-aged versus non-college aged individuals. In addition, we assessed the acute stress response to body composition measurement. Methods: Body fat percentage of 15 college aged (‘College Students’; CS) (mean = 19 years) and 16 non-college aged (‘Non-College Aged Students’; NCS) (mean = 39 years) males and females was assessed with the BodPod Body Composition Tracking System (Life Measurement Instruments, Con- cord, CA, USA). Participants indicated their perception of body fat and their desired body fat using a somatomorphic matrix. Salivary cortisol, heart rate and blood pressure were also measured. Data were analysed by analy- sis of variance and alpha was set at 0.05. Results: Mean (SD) percentage body fat of males [15.2% (6.1%] was signifi- cantly lower than that of females [28.4% (6.4%)] (P < 0.0001). Both CS and NCS females perceived their body fat to be lower (5%) than measured body fat and desired their body fat to be lower (12%) than measured (P < 0.05). CS and NCS male participants demonstrated the opposite result; both CS and NCS male populations perceived their body fat to be higher (5%) than measured body fat and desired their body fat to be higher (4%) than measured (P < 0.05). No differences between any groups were observed in heart rate, blood pressure or cortisol response to body fat mea- surement. Conclusions: Sex-related but not age-related differences in perceived, desired and measured percentage body fat were observed.