الفهرس 
Normal Nutrition and LiverOnly 14 pages are availabe for public view
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Abstract
Liver is the largest vital organ in the body and composed of many different cell types which are divided into parenchymal cells (hepatocytes) and non-parenchymal cells. The liver plays a crucial role in different metabolic processes of the body.
It acts as a factory. Concerning protein metabolism, it plays a major role in the metabolism of amino acids and proteins. It is the main site of amino acid degradation (deamination) and of urea synthesis. The liver also functions as a glucostate by maintaning glucose homoeostasis through: glycogenesis, glycogenolysis, gluconeogenesis, and glucolysis. Moreover it acts a crucial role in lipid metabolism and energy homeostasis through converting excess dietary glucose into fatty acids that are then exported to other tissues for storage and under chronic energy over-load situations the liver may serve as a surrogate reservoir for storing of excess fat, leading to the development of hepatic steatosis and steatohepatitis. Liver also has a fundamental role in regulating metabolism of vitamins and minerals including vit. A, iron and cupper.
Liver acts as a detoxifier by degradation and / or detoxification of harmful substances including foreign exogenous compounds (xenobiotics) or endogenous toxic substances through different metabolic pathways including biotransformation, urea cycle and glutamine cycle. Alcohol has its specific detoxification enzymes as alcohol dehydrogenase, microsomal ethanol-oxidizing system and catalase.
Different nutritional status will be reflected on the liver. Malnutrition refers to all deviations from adequate and optimal nutritional status, including undernutrition and over-nutrition. Both undernutrition and overnutrition affect liver function deviating it from normal state.
Undernutrition in infants and children is commonly known as protein energy malnutrition. It is classified to either dry (marasmus), oedematous (kwashiorkor) or combined type (marasmic kwashiorkor). Kwashiorkor is always associated with fatty liver. Several theories to explain its occurrence in kwashiorkor have been proposed: endocrine abnormalities, increased fat synthesis, redistribution from adipose tissue, reduced lipoprotein synthesis, abnormalities of lipoprotein lipase, and peroxisomal dysfunction. Also, the role of oxidative stress on the development of kwashiorkor has become the main focus of research. There is controversy whether hepatic steatosis occurs in marasmus or it is only a manifestation of kwashiorkor.
Obesity also has a negative impact on liver. The association between obesity and liver injury has been known since the 1800s. Several papers in the mid-1900s further reported a relationship between steatosis, progressive liver injury, and obesity. Obesity, a component of metabolic syndrome, is considered a major determinant for development of hepatic steatosis; what is commonly known as NAFLD. NAFLD is a spectrum of histologic liver disease ranging from steatosis to non-alcoholic steatohepatitis (NASH) to cirrhosis and in some patients to hepatocellular carcinoma. Insulin resistance and oxidative stress play the pivotal role in the accumulation of triglycerides within hepatocytes.
As malnutrition affects liver and lead to hepatopathy, also different liver diseases lead to malnutrition which in turn leads to progressive deterioration of liver functions. For example, Protein calorie malnutrition is found in 65–90% of patients with advanced liver disease and in almost 100% of candidates for liver transplantation. The primary etiologies of malnutrition are poor oral intake, altered sense of taste, nausea, early satiety due to massive ascites and malabsorption.
Malnutrition in that group of patients is associated with increased morbidity and mortality rates. Patients with cirrhosis who are malnourished have a higher rate of hepatic encephalopathy, infection, and variceal bleeding. They are also likely to have refractory ascites. There is a correlation between poor nutritional status and a decreased survival rate. Malnutrition is identified as an independent predictor of mortality in patients with cirrhosis.
The treatment of many liver diseases involves multi-drug regimens which can be associated with a variety of side effects. Although therapy with prescription medication is often unavoidable, lifestyle interventions can play a key role in maintenance of overall health augmenting medical therapy in patients with chronic liver disease. Lifestyle modifications are strongly recommended for patients with non-alcoholic fatty liver disease (NAFLD), hepatitis C virus (HCV), as well as patients who have undergone liver transplantation. These lifestyle modifications typically encompass both dietary intervention and physical activity goals.
Hippocrates, the ‘‘Father of Western medicine’’ wrote his famous dictum ‘‘Let food be thy medicine and medicine thy food’’ and started the philosophy of ‘‘food as medicine’’. Many foods proved to have beneficial effects on the liver by acting as oxygen radical scavenger, increasing regenerative power of hepatocytes, having anti-infilamatory and anti-fibrotic properties, anti-cancer, anti-fatigue, hepatoprotection, and so on. Marine foods, vegetables including broccoli, artichoks, garlic and carrot, olive oil, honey and many herbs are very recommended for hepatic patients and also to maintain our livers healthy.