Effects of short‐term energy restriction on liver lipid content and inflammatory status in severely obese adults: Results of a randomized controlled trial using 2 dietary approaches

Abstract

Short-term very-low-energy diets (VLEDs) are used in clinical practice prior to bariatric surgery, but regimens vary and outcomes of a short intervention are unclear. We examined the effect of 2 VLEDs, a food-based diet (FD) and a meal-replacement plan (MRP; LighterLife UK Limited, Harlow, UK), over the course of 2 weeks in a randomized controlled trial. We collected clinical and anthropometric data, fasting blood samples, and dietary evaluation questionnaires. Surgeons took liver biopsies and made a visual assessment of the liver. We enrolled 60 participants of whom 54 completed the study (FD, n = 26; MRP, n = 28). Baseline demographic features, reported energy intake, dietary evaluation and liver histology were similar in the 2 groups. Both diets induced significant weight loss. Perceived difficulty of surgery correlated significantly with the degree of steatosis on histology. There were reductions in the circulating inflammatory mediators C-reactive protein, fetuin-A and interleukin-6 between baseline (pre-diet) and post-diet. The diets achieved similar weight loss and reduction in inflammatory biomarkers. There were no significant differences in perceived operative difficulty or between patients' evaluation of diet satisfaction, ease of use or hunger frequency. Non-alcoholic fatty liver disease histology assessments post-diet were also not significantly different between diets. The results of this study show the effectiveness of short-term VLEDs and energy restriction, irrespective of macronutrient composition, although the small sample size precluded detection of subtle differences between interventions.

Efficacy of low‐ and very‐low‐energy diets in people with type 2 diabetes mellitus: A systematic review and meta‐analysis of interventional studies

“…This included 52% (16/31) of studies using a VLED and 85% (11/13) using an LED. Sufficient information on losses to follow‐up was provided by 26 studies; however, we found that in 15 of the 17 studies declaring any losses to follow‐up, participants were excluded from the analysis, with a median (IQR; range) of 4 (1‐8; 1‐14) participants dropping out . The remaining two studies opted for an intention‐to‐treat analysis, reporting 21 (14% of all participants) and four (4%) drop‐outs, respectively .…”

“…Patient characteristics such as age, sex and duration of diabetes, were included in 39, 39 and 28 studies, respectively, and drug treatment before and during the study in participants dropping out. 44,47,[50][51][52][53][54][55][56][57][58][59][60][61] The remaining two studies opted for an intention-to-treat analysis, reporting 21 (14% of all participants) and four (4%) drop-outs, respectively. 13,48 Adherence was not quantitatively or systematically assessed in the large majority of studies.…”

Effects of combined low‐dose spironolactone plus vitamin E vs vitamin E monotherapy on insulin resistance, non‐invasive indices of steatosis and fibrosis, and adipokine levels in non‐alcoholic fatty liver disease: a randomized controlled trial

“…Despite its high prevalence and despite intensive research, the treatment of NAFLD remains an unmet medical need . Weight loss and exercise remain the cornerstones of its management, but both are difficult to achieve and sustain . Vitamin E improves hepatic steatosis and inflammation and may be administered in selected patients with NASH…”

Nutritional science: Diet, lifestyle and health

“…The bariatric surgery team, hepatologists, histopathologists, molecular biologists and nutritionists/physiologists collaborated to undertake this study (Baldry et al . ). To examine the effects of the diets on the liver, biopsies of participants in the two diet groups were taken during surgery.…”

“…While there were no differences in liver fat content or indices of inflammation between the groups, the histological assessment of the liver biopsies showed lower levels of fat and less fibrosis than would be expected from people with this degree of obesity and not on a reduced energy diet (Baldry et al . ). These projects show the benefits of linking clinical practice and nutritional science to provide insights into the metabolic and nutritional disturbances seen in gastrointestinal and bariatric surgery patients.…”