Applied nutritional investigationDietary patterns and non-alcoholic fatty liver disease in a Greek case–control study
Introduction
Non-alcoholic fatty liver disease (NAFLD) is considered a potential new component of metabolic syndrome (MetS) [1]. It is characterized by excessive flux of fatty acids (FA) and triacylglycerol (TG) accumulation in the liver, primarily activated by dietary factors, obesity, and insulin resistance [2]. This results in increased inflammation and mitochondrial dysfunction in the liver—conditions that lead to fibrosis and cell apoptosis. Moreover, genetic and epigenetic factors, and gut microbiome dysfunction, further induce hepatic steatosis, inflammation, and oxidative stress. This multiple-hit model of NAFLD pathogenesis indicates the complexity of the disease and highlights the need to control liver and systemic inflammation.
As mentioned previously, diet is a major contributor to the pathogenesis of NAFLD but it also is an integral part of its treatment [3]. Overall, maintaining a normal body weight and a balanced diet has been shown to reduce inflammation and promote health. Regarding NAFLD, previous studies have demonstrated that excessive energy intake is a key determinant of disease onset and progression [4]. Increased consumption of fat, especially saturated fatty acids (SFA), and simple sugars also have been positively associated with the disease [5]. On the other hand, energy restriction, high protein, high ω-3 polyunsaturated fatty acids (PUFA), and antioxidants intake have been inversely associated with hepatic steatosis.
Many epidemiologic studies have examined the effect of single nutrients or foods on the risk for NAFLD; however, only a few have investigated the role of diet as a whole. Greater adherence to the Mediterranean diet decreases the risk for NAFLD and NAFLD-related diseases, but it also is believed to reduce the severity of the disease [6], [7]. The Mediterranean diet mainly consists of plant foods, fish, and low amounts of red meat. These food groups are rich in antioxidant vitamins and minerals, ω-3 PUFA, and dietary fibers, which are believed to be the components that give the Mediterranean diet its beneficial properties. On the other hand, dietary patterns characterized by increased consumption of red meat, fast foods, sweets, refined cereals, and sweetened soft drinks are rich in processed sugars and fat and have been associated with higher risk for NAFLD [8], [9], [10].
To our knowledge, there are no available data regarding dietary patterns of European patients with NAFLD. Against this background, the aim of this study was to assess a posteriori-derived dietary patterns of Greek patients with NAFLD and controls and to estimate the effect of these patterns on disease and its parameters.
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Study population
Study participants were randomly and consecutively recruited from volunteers visiting the Outpatient Clinics of the First Department of Propaedeutic Medicine, Laiko General Hospital, from June 2012 to February 2015. Adults with no self-declared concomitant liver injury at the time of recruitment (viral, autoimmune, genetic, or drug-induced), and no self-declared excessive alcohol intake were screened for the disease. We excluded individuals meeting the following criteria:
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>65 y of age,
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Presence
Results
The present sample consisted of 134 patients with NAFLD and 217 controls. The main characteristics of the sample are presented in Table 1. Patients were older, less educated, less physically active, and smoked more than controls (P < 0.05). Moreover, the patients had a higher prevalence of obesity and MetS and had higher levels of disease-related biochemical markers than controls (P < 0.05).
The following four dietary patterns derived from the factor analysis:
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The fast food–type pattern consisted
Discussion
In the present case-control study, four dietary patterns of 351 individuals with and without NAFLD were identified. We demonstrated associations between dietary patterns, NAFLD, and NAFLD-related biomarkers, independently of known confounding factors.
A greater adherence to a fast food–type dietary pattern was associated with higher odds for NAFLD. However, only individuals in the highest quartile compared with the lowest had a statistically significantly higher NAFLD risk, after adjusting for
Conclusion
Patients with NAFLD were more adherent to a fast food–type dietary pattern than to a prudent, high-protein, or unsaturated FA diet. It can be concluded that following a fast food–type dietary pattern significantly increases the odds of NAFLD, but also increases CRP and uric acid levels. Moreover, higher consumption of a prudent diet, characterized by vegetables, fruits, legumes, fish, and olive oil, and a diet rich in unsaturated FAsreduces several NAFLD-related biomarkers. Nevertheless, larger
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2022, South African Journal of BotanyCitation Excerpt :This dietary pattern also favors the substantial increase in the flow of fatty acids and concentration of triacylglycerides in the liver (Buzzetti et al. 2016), typical aspects of non-alcoholic fatty liver disease. These aspects, in turn, increase the inflammatory process and mitochondrial dysfunction in the hepatic tissue and subsequent fibrosis and programmed cell death (Kalafati et al. 2019). From another perspective, there is evidence that dietary patterns in particular, likewise specific nutrients and functional compounds, play important roles in the prevention and treatment of cardiovascular diseases (CVD) by positively modifying the main risk factors, particularly plasma lipoproteins (Eckel et al. 2014; Siri-Tarino and Krauss 2016).
Hepatic cytochrome P450 function is reduced by life-long Western diet consumption in guinea pig independent of birth weight
2021, Life SciencesCitation Excerpt :It is possible that this NAFLD related hepatic CYP dysfunction may have implications for the efficacy of liver-mediated drug clearance, which may further dysregulate whole-system homeostasis and exacerbate disease burden. Although postnatal WD is a known risk factor for NAFLD [9,16,17], recent evidence has also demonstrated that perturbed in utero fetal growth is an independent risk factor for the development of NAFLD [18]. Animal models and human population studies have both shown that in utero insults that reduce fetal growth are associated with the development of metabolic disease in later life [19–21].
Dietary patterns and risk of non-alcoholic fatty liver disease in adults: A prospective cohort study
2021, Clinical NutritionCitation Excerpt :Therefore, the analysis of dietary patterns consisting of complex foods with many nutrients has emerged as an alternative and complementary approach to examining the association between overall diet and the risk of NAFLD [8]. Findings from many cross-sectional studies [9–15] and case-control studies [16–20] in adults investigating the association between dietary patterns and NAFLD are mixed. In addition, these studies have methodological limitations such as the cross-sectional design.
Fatty liver index relationship with biomarkers and lifestyle: result from RaNCD cohort study
2023, BMC Gastroenterology
This study was funded by the project “Obesity and Metabolic Syndrome: Dietary Intervention with Greek Raisins in NAFLD/NASH. Investigation of Molecular Mechanisms” reviewed and approved by the Greek General Secretariat for Research and Technology (Cooperation 890/2009).