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

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.