Dietary insulin index and dietary insulin load in relation to non-alcoholic fatty liver disease: a cross-sectional study.

ABSTRACT

OBJECTIVE: Postprandial hyperinsulinaemia plays a key role in the development of non-alcoholic fatty liver disease (NAFLD). Diet is a potential factor affecting serum insulin levels. This study aimed to examine the relations of dietary insulin index (DII) and dietary insulin load (DIL) to the risk of NAFLD. DESIGN: This study was a cross-sectional study. DII and DIL were calculated using the dietary data obtained from the FFQ. Fatty liver index ≥ 60 and the confirmation of a gastroenterologist were required to diagnose NAFLD. SETTING: Community-based study. PARTICIPANTS: A total of 3158 people (46·7 % male), aged 40·57 ± 8·25 years, participated in this study in Tehran, Iran from April 2016 to December 2019. RESULTS: The prevalence of NAFLD was 29·9 % (21·59 % in males and 33·74 % in females). In the fully adjusted model controlled for sex, age, energy intake, BMI, smoking, physical activity and education, DII was significantly associated with the increased risk of NAFLD in males (OR 2·74, 95 % CI = 1·75, 4·31; P-trend = ≤0·001) and females (OR 2·26, 95 % CI = 1·39, 3·69; P-trend = 0·005). A significant relationship was also detected between DIL and NAFLD in females (OR 2·90, 95 % CI = 1·70, 4·93; P-trend ≤0·001) but not in males (OR 1·33, 95 % CI = 0·84, 2·10; P-trend = 0·13). CONCLUSIONS: Adherence to a diet with a high DII and DIL may be related to the increased risk of NAFLD. These results may be useful for healthcare providers to design appropriate preventive measures for people at risk of NAFLD.