Salivary Testosterone in Men: Diurnal Variation and Post-Prandial Responses

To investigate whether salivary (free) testosterone is subject to similar prandial variations reported for serum total testosterone.

Study 1:

Assessment of diurnal variation in salivary testosterone adjusted for prandial state in 20 healthy men.

Study 2:

Measurement of salivary and serum testosterone and related biomarkers before and after a standard 75g oral glucose load in 40 men.

For 1st part of study -volunteers:

Inclusion criteria

• Aged 20-60 years
• Male

Exclusion criteria

• Subjects with learning disability or those lacking mental capacity to give consent.
• On (prescribed and over-the-counter) medication and herbal remedies known to affect androgen metabolism.
• Known hypogonadism.
• Conditions known to affect androgen metabolism, including chronic inflammatory diseases, chronic liver disease, chronic kidney disease and thyroid dysfunction.
• Any co-morbidity.
• Periodontal disease.
• Dental work 48 hours prior to the test.
• Exercise on the day, prior to and during sampling periods.
• Brushed teeth within 1hr prior to sample collection.
• Obesity defined as a body mass index (BMI) of greater than 29.9 kg/m2As

2nd part of study for glucose load - oral glucose tolerance test (OGTT):

Inclusion criteria

• Aged over 40-60 years.
• Attending for routine 75 g OGTT

Exclusion criteria

• Subjects with learning disability or lacking mental capacity to give consent.
• On (prescribed and over-the-counter) medication and herbal remedies known to affect androgen metabolism.
• Known hypogonadism.
• Conditions known to affect androgen metabolism, including chronic inflammatory diseases, chronic liver disease, chronic kidney disease and thyroid dysfunction.
• Subjects with difficult venous access.
• Periodontal disease.
• Dental work 48 hours prior to the test.
• Brushed teeth within 1hour prior to sample collection.
• Exercise on day prior to and during the OGTT.