Endocrine Abstracts

Introduction: Beneficial influence of vegetarian dietary habits in reducing common risk factors of metabolic syndrome has been recently evidenced. However, adiponectin production and secretion has been scarcely studied in vegetarians, despite its important potential in recovering metabolic homeostasis by reducing inflammation and insulin resistance.

The aim of this study was to evaluate the influence of vegetarian diet on serum adiponectin levels and it’s association to the established inflammatory and metabolic biomarkers.

Methods/design: Total serum adiponectin (ADN), leukocytes (L), CRP, plasma glucose (PG), insulin (INS), and uric acid (UA) were measured in healthy, non-obese, age-matched vegetarian (n=40; M/F=16/24) and omnivore subjects (n=39; M/F=15/24). HOMA-2 model was used for the assessment of β-cell function (BS), insulin sensitivity (IS), and insulin resistance index (IRI).

Results: Serum ADN levels were significantly higher in female vegetarians than the respective omnivore controls (14.2±5.82 mg/l vs 10.82±3.29 mg/l; P=0.017), whereas no dietary-associated difference was observed in male vegetarian and omnivore subjects respectively (6.87±2.57 mg/l vs 6.74±3.07 mg/l; P=0.898). Stepwise multiple regression analysis identified uric acid as the significant negative determinant of ADN in vegetarians (r_partial=−0.4585, P=0.002), while in omnivore subjects only BMI was found to be significantly associated to ADN levels (r_partial=−0.4439, P=0.016). In comparison to controls, significantly lower INS (47.6±19.2 pmol/l vs 57.7±23.7 pmol/l; P=0.042) and IRI (1.01±0.42 vs 1.22±0.49; P=0.041), as well as higher BS (115.5±42.9% vs 94.2±35.3%; P=0.019) were found in vegetarians.

Conclusion: Vegetarian dietary habits result into improved insulin sensitivity and β-cell function. Gender diversity in adiponectin response and inverse association to uric acid indicate distinct effects of vegetarian diet to adipose tissue metabolism.

Disclosure: This work was supported by the Croatian Ministry of Science, Education and Sports (grant numbers 022-0222148-2125 and 045-1191348-0139).