Yogurt improves insulin resistance and liver fat in obese women with nonalcoholic fatty liver disease and metabolic syndrome: a randomized controlled trial.

Abstract

BACKGROUND:

Because consumption of conventional yogurt has beneficial effects in a healthy population, and insulin resistance (IR) is the mutual pathogenesis in nonalcoholic fatty liver disease (NAFLD) and metabolic syndrome (MetS), we hypothesized that yogurt would ameliorate IR in patients with NAFLD and MetS.

OBJECTIVES:

The aim of this study was to investigate the effects of yogurt on IR and secondary endpoints including liver fat, gut microbiota, and serum biomarkers of inflammation and oxidative stress in obese women with NAFLD and MetS.

METHODS:

One hundred obese women aged 36-66 y with both NAFLD and MetS were randomly assigned to consume 220 g/d of either conventional yogurt or milk for 24 wk. At baseline and week 24, we measured anthropometric indices, serum glucose, insulin, lipids, and cytokines in all participants, and liver fat and gut microbiota in 20 participants randomly selected from each group.

RESULTS:

Forty-eight participants from the yogurt group and 44 from the milk group completed the intervention. Compared with milk, yogurt significantly decreased the homeostasis model assessment of insulin resistance (-0.53; 95% CI: -1.03, -0.02), fasting insulin (-2.77 mU/L; 95% CI: -4.91, -0.63 mU/L), 2-h insulin (-25.5 mU/L; 95% CI: -33.0, -17.9 mU/L), 2-h area under the curve for insulin (-29.4 mU/L · h; 95% CI: -44.0, -14.8 mU/L · h), alanine aminotransferase (-4.65 U/L; 95% CI: -8.67, -0.64 U/L), intrahepatic lipid (-3.44%; 95% CI: -6.19%, -0.68%), and hepatic fat fraction (-3.48%; 95% CI: -6.34%, -0.63%). Yogurt also decreased serum LPS (-0.31 EU/mL; 95% CI: -0.48, -0.14 EU/mL), fibroblast growth factor 21 (-57.76 pg/mL; 95% CI: -86.32, -29.19 pg/mL), lipids, and biomarkers of inflammation and oxidative stress, and altered gut microbiota composition. Mediation analysis showed that yogurt may improve IR by reducing serum lipids, inflammation, oxidative stress, and LPS.

CONCLUSIONS:

Yogurt was better than milk at ameliorating IR and liver fat in obese Chinese women with NAFLD and MetS, possibly by improving lipid metabolism, reducing inflammation, oxidative stress, and LPS, and changing the gut microbiota composition. This trial was registered at www.chictr.org.cn as ChiCTR-IPR-15006801.

• Authors: Yang Chen, Rennan Feng, Xue Yang, Jiaxing Dai, Min Huang, Xiaoning Ji, Yong Li, Akinkunmi Paul Okekunle, Guanghui Gao, Justina Ucheojor Onwuka, Xiuyu Pang, Cheng Wang, Chunlong Li, Ying Li, Changhao Sun
• Journal: The American journal of clinical nutrition (Am J Clin Nutr) Vol. 109 Issue 6 Pg. 1611-1619 (06 01 2019) ISSN: 1938-3207 [Electronic] United States
• PMID: 31136662 (Publication Type: Journal Article, Randomized Controlled Trial, Research Support, Non-U.S. Gov't)
• Copyright: Copyright © American Society for Nutrition 2019.

Chemical References

• Fats
• fibroblast growth factor 21
• Fibroblast Growth Factors

Topics

• Adult
• Aged
• Fats (metabolism)
• Female
• Fibroblast Growth Factors (genetics, metabolism)
• Gastrointestinal Microbiome
• Humans
• Insulin Resistance
• Liver (metabolism)
• Male
• Metabolic Syndrome
• Middle Aged
• Non-alcoholic Fatty Liver Disease (diet therapy, metabolism, microbiology)
• Obesity (diet therapy, metabolism)
• Oxidative Stress
• Yogurt (analysis)