Beneficial effects of the ketogenic diet on nonalcoholic fatty liver disease: A comprehensive review of the literature

Abstract

Summary Nonalcoholic fatty liver disease (NAFLD) is a major cause of chronic liver disease, characterized by hepatic fat accumulation and possible development of inflammation, fibrosis, and cancer. The ketogenic diet (KD), with its drastic carbohydrate reduction, is a now popular weight loss intervention, despite safety concerns on a possible association with fatty liver. However, KDs were also reported to be beneficial on hepatic pathology, with ketone bodies recently proposed as effective modulators of inflammation and fibrosis. If the beneficial impact of weight loss on NAFLD is established, less is known on the effect of macronutrient distribution on such outcome. In a hypocaloric regimen, the latter seems not to be crucial, whereas at higher calorie intake, macronutrient ratio and, theoretically, ketosis, may become important. KDs could positively impact NAFLD for their very low carbohydrate content, and whether ketosis plays an additional role is unknown. Indeed, several mechanisms may directly link ketosis and NAFLD improvement, and elucidating these aspects would pave the way for new therapeutic strategies. We herein aimed at providing an accurate revision of current literature on KDs and NAFLD, focusing on clinical evidence, metabolic pathways involved, and strict categorization of dietary interventions.

The psychological impact of COVID-19 pandemic on patients included in a bariatric surgery program

“…The strong connection between mental status and food behavior warrants first of all an accurately targeted psychological support in order to favor compliance to dietary treatments. However, some dietary manipulations including certain foods [34,35], food supplements [36,37], and dietary patterns [38][39][40][41][42][43] together with pharmacological treatment [44,45] have been shown to impact appetite and mood and/ or proved particularly beneficial in subjects with severe obesity and in post-bariatric patients. Such measures should be therefore taken into consideration in the next months in order to favor dietary adherence and metabolic improvement, leveraging a multidisciplinary approach to treat those severely obese seeking bariatric surgery and those who have lost weight but need lifelong follow-up after bariatric surgery [46].…”

Peroxisome Proliferator-Activated Receptors and Their Novel Ligands as Candidates for the Treatment of Non-Alcoholic Fatty Liver Disease

“…Interestingly, these changes are associated with an alteration in the composition of the gut microbiota [160]. Ketone bodies produced in response to carbohydrate restriction can induce additional protective effects in NAFLD, such as anti-oxidant and anti-inflammatory effects [161]. Another recent study analyzed the effects of isocaloric diets rich in animal proteins or plant proteins for 6 weeks in diabetic patients with NAFLD and found that both high-protein diets reduce liver fat [162].…”

Scientific evidence underlying contraindications to the ketogenic diet: An update

“…60 A relevant body of evidence suggests a protective role of KDs in its pathogenesis, possibly going beyond simple weight loss: virtually all studies assessing liver fat content report positive results after all kinds of KDs, including those with a high fat content. 9 Noteworthy, malnutrition is a common issue in chronic liver disease. 61 The 2019 Guidelines of the European Association for the Study of the Liver therefore recommend consuming an adequate number of calories and protein.…”

“…95 However, administration of a KD to frail and/or elderly subjects might not be advisable due to several reasons. However, it has been proposed that the KD might be a possible bridge treatment for those with AN in order to avoid starvation and increase patient compliance, 9 although no clinical evidence has been reported to support this hypothesis to date.…”