Gender differences in facial skin dielectric constant measured at 300 MH z

Background/purpose Skin tissue dielectric constant ( TDC ) measurements at 300 MH z provide non‐invasive data on free and bound tissue water. TDC ‐data is available for some body sites, but most is for female forearm. Contrastingly, there are no data on face‐skin or comparative data between genders. Our goals were to obtain facial‐ TDC reference values and determine if TDC ‐values differ between genders. Methods TDC was measured at forehead, cheek, and forearm in 60 young adults (30 men) to a 1.5‐mm depth. Measured TDC ‐values were compared with TDC ‐values calculated using skin‐thickness data. Results Measured TDC ‐values ranged from 39.6 ± 2.9 at male‐forehead to 28.2 ± 2.4 at female forearm and were significantly different ( P  < 0.001) among each site in the order forehead > cheek >forearm. Male TDC ‐values were greater than female TDC ‐values ( P  < 0.01) with differences from 5.6% at forehead to 11.3% at forearm. Calculated TDC ‐values incorporating site and gender skin‐thickness differences yielded TDC ‐values at the most 3% different from measured values. Conclusion Gender differences should be considered in clinical studies in which men and women are included in a common study population with respect to experimental design and data interpretation. This is especially true if absolute TDC ‐values are of interest rather than changes in TDC ‐values on the same subject subsequent secondary to an intervention.