Objectives: Infection with specific pathogens may lead to increased adiposity: a specific adiposity-promoting effect of Ad36 human adenovirus, without the involvement of neurological mechanisms, was reported. The aim of this study is to investigate whether non-diabetic patients with earlier Ad36 infection show greater degrees of overweight obesity, of Insulin Resistance (IR), assessed by homoeostasis-model assessment (HOMA), and/or of other related factors. Moreover, the relationship, if any, among these factors and an earlier Ad36 infection, and the hypothesis of a mechanism involving IR are investigated. Subjects: Ad36 seropositivity is assessed in 68 obese and 135 non-obese subjects, along with body composition, HOMA and laboratory investigations. Results: Age, body mass index (BMI), waist-hip ratio, blood pressure, insulin, HOMA and triglycerides are significantly greater in the Ad36 seropositive group. Ad36 seropositivity, along with HOMA and total cholesterol, explains BMI variance. No Ad36 seropositivity effect to HOMA could be envisaged by the same statistical model. Conclusion: A significant association of Ad36 seropositivity with obesity and with essential hypertension in human beings is suggested by our study; this association is mostly significant in women. Our results do not support that any Ad36 adipogenic adenovirus effect is operating in human obesity through an insulin-resistance-related mechanism. Ad36 seropositive status could also be a hallmark of a clinical-metabolic profile possibly preceding obesity and diabetes in non-obese patients.

A possible opposite, if not antagonistic, role of coffee with regard to overweightness and insulin resistance, similar to that reported in hepatocarcinoma and cirrhosis, is envisaged in the natural history of NAFLD.

Ad36 seropositivity is not associated with a significant difference of IR in NAFLD patients, but is associated with a greater adiposity. Ad36 seropositivity is associated with a lower occurrence of NAFLD and bright liver, which, conceivably, is not directly mediated by IR.

Liver US BLS appears to be a useful tool, both alone and along with other US measurements and body weight changes, for the assessment of clinical-metabolic amelioration in patients treated with dietetic interventions. The clinical-diagnostic role, if any, of other assessed laboratory analyses, in the subset of NAFLD, does not appear to be definite.

The combination of coffee consumption and HRT could lower insulin resistance in postmenopausal women. In overweight women, greater insulin sensitivity is associated with intake of espresso coffee and not with HRT; in normal weight women, only HRT is associated with lower insulin resistance.