Gender differences in the saliva of young healthy subjects before and after citric acid stimulation

•Confirming the gender salivary differences before & after acid stimulation•Confirming the gender salivary differences by three sampling methods•Substantial gender differences in salivary pH and flow of saliva exist.•No gender difference in sAA was evident.

BackgroundGender differences in the function and anatomical features of salivary glands are well known. However, specific gender differences in the biochemical composition and salivary flow rate (SFR) remain uncertain. Collection methods affect the assessment of the salivary composition and SFR, which are also highly affected by acid stimulation.MethodsIn the present study, we analyzed the differences in salivary characteristics of SFR, pH and salivary α-amylase (sAA) for 28 females and 27 males before and after citric acid stimulation, as measured by 3 different collection methods sequentially.ResultsSalivary pH values were significantly lower in females than that in males, both before and after stimulation, irrespective of collection methods. Salivary pH consistently increased after acid stimulation in both genders. Mean SFR in females before acid stimulation was significantly lower than that in males in all 3 samples collected. No gender difference in sAA was evident.ConclusionSubstantial gender differences in biochemistry and flow of saliva exist, and these findings are robust, as evidenced by reasonable consistency of the data among different saliva sampling methods.