Diet, Weight Loss and Nonalcoholic Fatty Liver Disease (NAFLD) pp. 301-312
Authors: (Maria Cristina Elias, Edison R. Parise, Luciana Carvalho, Fany Govetri Sena Crispim, Bruna Elias Rebello, Division of Gastroenterology and Hepatology, Federal University of São Paulo, Brazil)
Abstract: It is estimated that 20 to 30% of the adult population in developed countries are suffering from nonalcoholic fatty liver disease (NAFLD), and 3.5 a 5% from nonalcoholic steatohepatites (NASH). In obese subjects there is an estimated prevalence of 50 to 90% of NAFLD, and 19% of NASH (Preiss and Sattar 2008). Dyslipidemia, viceral obesity, insulin resistance, and type 2 diabetes mellitus are risk factors usually present in NAFLD, linking the disease to metabolic syndrome, a common finding in many of NAFLD patients (Collantes, Ong et al. 2004; Perez-Aguilar, Benlloch et al. 2004; Adams, Angulo et al. 2005; Angelico, Del Ben et al. 2005; Suzuki, Lindor et al. 2005; Utzschneider and Kahn 2006; Merat, Aduli et al. 2008). .At present, there is no standard recommended treatment for NAFLD/NASH (Mendez-Sanchez, Arrese et al. 2007). The treatment includes lifestyle modifications, and the use of pharmacological agents, as antioxidants, lipid lowering and insulin sensitizers (Siebler and Galle 2006; Cave, Deaciuc et al. 2007; Mendez-Sanchez, Arrese et al. 2007). The nutritional treatment is related to diseases associated with NAFLD, as obesity, dyslipidemia, diabetes mellitus and hypertension (Nehra, Angulo et al. 2001; Grattagliano, Portincasa et al. 2007). The American Gastroenterological Association (AGA) recommends a target of 10% of the baseline weight as an initial goal of weight loss if overweight is present (i.e. BMI higher than 25 kg/m²). Weight loss should be gradual (over 6 months). According to the researchers, it can be reached by associating dietary restriction to physical activity. Both of them seem to act favorably in IR (Iniative 2000; Suzuki, Lindor et al. 2005; Adams and Angulo 2006; Siebler and Galle 2006; Grattagliano, Portincasa et al. 2007; Mendez- Sanchez, Arrese et al. 2007; Yamamoto, Iwasa et al. 2007). Researches have also shown the effectiveness of weight loss in the normalization of liver enzymes, in the reversal of insulin resistance and hepatic steatosis, with a balanced diet, rich in fiber, antioxidants, and n – 3 fatty acids (Ueno, Sugawara et al. 1997; Okita, Hayashi et al. 2001; Delzenne, Daubioul et al. 2002; Harrison, Kadakia et al. 2002; Dixon, Bhathal et al. 2004; Yamamoto, Iwasa et al. 2007; Elias, Parise et al. 2009).