The effects of onion consumption on treatment of metabolic, histologic, and inflammatory features of nonalcoholic fatty liver disease

BACKGROUND: The aim of this study was to evaluate the effects of onion powder consumption on treatment of Non-alcoholic Fatty Liver Disease (NAFLD) in an experimental model of disease. METHODS: Sprague–Dawley rats were fed high-fat (HF) diet for seven weeks to induce the NAFLD. Then, they were treated by either the same diet (HF), or high-fat diet plus 7 % onion powder (HF + onion), or chow diet (control), or chow diet plus 7 % onion powder (control + onion)ad libitum for four weeks. Serum levels of fasting glucose, triglyceride, cholesterol, liver enzymes, insulin, and hepatic tumor necrosis factor-alpha (TNF-α) gene expression were determined. Hepatic histology was examined by Hematoxylin and Eosin stain. RESULTS: Dietary food intakes and weigh gain were significantly more in animals fed control + onion diet in comparison to the other groups. Animals fed control or control + onion diet had significantly lower plasma levels of hepatic enzymes, lipid profile, glycemic indices, and hepatic TNF-α gene expression as compared with HF diet fed groups; however, there was no significant difference in the histopathologic features of NAFLD among different groups. CONCLUSION: Our results indicate that onion consumption can be effective in NAFLD management when it is combined with a healthy diet. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s40200-016-0248-4) contains supplementary material, which is available to authorized users.