LGI Diet and NAFLD
Research type
Research Study
Full title
Effects of an iso-energetic low glycemic index (GI) diet on liver fat accumulation and gut microbiota composition in patients with non- alcoholic fatty liver disease (NAFLD)
IRAS ID
262245
Contact name
Amina Al-Awadi
Contact email
Sponsor organisation
University of Nottingham
Duration of Study in the UK
3 years, months, days
Research summary
Research summary: Non-alcoholic fatty liver disease (NAFLD) is a growing global health problem which may arise as a consequence of dietary habits and inactive lifestyle. It develops when a person’s liver cells consist of more than 5% of fat. People with NAFLD often suffer from recurrent high blood sugar which puts them at high risk of developing diabetes. We think that liver fat accumulation is highly affected by eating certain foods with a high Glycaemic index(GI), (meaning that they result in higher blood sugar levels soon after being eaten) on a daily basis. So, a diet containing more foods with low GI could be beneficial to treat or manage NAFLD. The GI of food is a ranking system of carbohydrates on a scale from 0- 100 depending on how quickly each type of carbohydrate raises blood sugar after eating. Foods with a GI ˃70 are ranked as high GI foods, whereas foods with a GI ˂55 are classed as low GI foods. Consumption of a large amount or proportion of high GI foods is linked to higher levels of specific bacteria in the gut (called gut microbiota) which may trigger increased liver fat accumulation.
The purpose of this study is to compare liver fat contents in people with NAFLD after following a low GI diet versus a high GI diet without calorie restrictions. We propose two different diets, each to be followed for 2 weeks by all study participants. We will also examine their gut bacteria composition before and after each period. This will help us to develop treatment and strategies to manage the factors that increase NAFLD progression.Summary of results- This 2-week dietary intervention trial investigated the effects of low glycemic index (LGI) versus high glycemic index (HGI) diet in 16 participants with non-alcoholic fatty liver disease (NAFLD). Changes in hepatic fat accumulation, blood biomarkers and gut microbiota composition were determined in 7 participants who completed the study.
The LGI diet resulted in an observable reduction in liver fat levels relative to baseline values using both MRI scan (Magnetic Resonance Imaging) and transient elastography (CAP-FibroScan™) methods, with a significant positive correlation between the two methods. These observations were compatible with changes in blood sugar biomarkers, lipids, and inflammatory biomarkers. The LGI diet was also associated with a significant reduction in body weight, BMI (body mass index), and appetite scores. Both LGI and HGI diets resulted in changes in the composition of the gut microbiome when compared with baseline profiles.
This study demonstrated the feasibility of undertaking a 2-week intervention enabling comparison between LGI and HGI diets. Whilst recognising the small sample size, the observed study outcome measures are compatible with the hypothesis that a LGI diet results in a reduction in liver fat compared with a HGI diet. Replication in a larger, longer trials is necessary.REC name
East Midlands - Nottingham 2 Research Ethics Committee
REC reference
19/EM/0291
Date of REC Opinion
13 Nov 2019
REC opinion
Further Information Favourable Opinion