Circadian fluctuations in saliva biochemical composition: A pilot study

Area of Science:

• Biochemistry
• Chronobiology
• Oral Health

Background:

• Saliva is a non-invasive diagnostic fluid.
• Circadian influences on saliva biochemistry are not well understood.

Purpose of the Study:

• To investigate circadian variations in unstimulated whole saliva composition.
• To assess the impact of daily rhythms on salivary pH, protein, glucose, and ions.

Main Methods:

• Eight healthy adults provided saliva samples over 24 hours at six time points.
• Analyzed pH, total protein, glucose, and ions.
• Used repeated measures ANOVA for statistical analysis.

Main Results:

• No significant circadian variations found for calcium, phosphate, peroxide, pH, or total protein.
• Significant circadian fluctuations observed for lactate, nitrate, nitrite, ammonium, and glucose.
• Specific analytes showed distinct time-of-day peaks.

Conclusions:

• Circadian rhythm has a limited effect on the overall biochemical profile of unstimulated saliva.
• Specific salivary analytes fluctuate significantly over 24 hours.
• Standardized saliva collection times are crucial for accurate diagnostics.