UNIT 1 - LIVER AND GALLBLADDER DISEASE MANAGEMENT |
|
What's damaging the liver?
Nonalcoholic fatty liver disease Article review Video review |
OBJECTIVES:
- Identify factors that causes damage to the liver
- Discuss on Nonalcoholic fatty liver disease
- Nutrition Guide for Clinicians, Neal Barnard, MD, 2009
- Nutrition Facts, Michel Greger, MD
- Souza MR, Diniz Mde F, Medeiros-Filho JE, et al. Metabolic syndrome and risk factors for nonalcoholic fatty liver disease.
What's damaging the Liver?
Anything that put inside our mouth may affect our liver. Alcohol is commonly known as a cause of liver damage but there are so many things that can damage liver cells and people always caught unaware. Too much sugar for example, can harm the liver. Too much refined sugar in many different forms including high-fructose corn syrup which is always used in processed products causes a fatty buildup that can lead to liver disease. Remember that liver uses fructose to make fat, and some studies show that sugar can be as damaging to the liver as alcohol even in person who is not overweight. Studies also show that people who drink soft drinks habitually are more likely to develop non-alcoholic fatty liver disease (NAFLD) which may be due to the high fructose component in these beverages.
Some herbal supplements and plant substances processed in the laboratories and taken as alternative remedy may not be good for the liver as well. One example is an herb called kava which is widely used for many types of ailments widely used in some countries in the South Pacific the United States. It has been banned or restricted in some countries but is continually utilized even in some developed countries. It is always prudent to consult with physicians who had training and exposure to this type of discipline as it won't also make sense to consult with physicians who had no education on integrating herbs or plant substances in medical care.
Obesity is another factor that may cause damage to the liver tissues. Extra fat can build up in the liver cells and lead to non-alcoholic fatty liver disease (NAFLD). It is a reversible damage in the liver and so management should be considered as it may lead to scarring which is an irreversible condition also known as cirrhosis.
Too much intake of certain Fat soluble vitamins such as Vitamin A taken as a pill can also cause liver damage. We need vitamin A and it's always fine to get it from fruits and vegetables. But high doses of vitamin A supplementation can be a problem to the liver.
Tans fats is another food component that causes liver damage. Trans fat is a man-made fat found in many different forms of food and baked goods. It improves texture, taste and shelf life of food and so it's mostly used as additive in various processed goods. Often times, trans fat is hidden behind the name "partially hydrogenated" ingredients. A diet high in trans fat will result to weight gain which is not favorable for the liver.
Some herbal supplements and plant substances processed in the laboratories and taken as alternative remedy may not be good for the liver as well. One example is an herb called kava which is widely used for many types of ailments widely used in some countries in the South Pacific the United States. It has been banned or restricted in some countries but is continually utilized even in some developed countries. It is always prudent to consult with physicians who had training and exposure to this type of discipline as it won't also make sense to consult with physicians who had no education on integrating herbs or plant substances in medical care.
Obesity is another factor that may cause damage to the liver tissues. Extra fat can build up in the liver cells and lead to non-alcoholic fatty liver disease (NAFLD). It is a reversible damage in the liver and so management should be considered as it may lead to scarring which is an irreversible condition also known as cirrhosis.
Too much intake of certain Fat soluble vitamins such as Vitamin A taken as a pill can also cause liver damage. We need vitamin A and it's always fine to get it from fruits and vegetables. But high doses of vitamin A supplementation can be a problem to the liver.
Tans fats is another food component that causes liver damage. Trans fat is a man-made fat found in many different forms of food and baked goods. It improves texture, taste and shelf life of food and so it's mostly used as additive in various processed goods. Often times, trans fat is hidden behind the name "partially hydrogenated" ingredients. A diet high in trans fat will result to weight gain which is not favorable for the liver.
Nonalcoholic Fatty Liver Disease
Nonalcoholic fatty liver disease (NAFLD) comprises a spectrum of conditions characterized by hepatic fat accumulation in the absence of alcoholic abuse, with fat making up at least 10% of the liver tissue (steatosis). Nonalcoholic steatohepatitis (NASH), in which fat accumulation is accompanied by inflammation, is the most common type of NAFLD and the most common form of liver disease in many developed and even developing countries. Clinically, NASH may be indistinguishable from alcoholic hepatitis, but it is most often a subclinical disease.
The progressive accumulation of triglycerides in hepatic tissue results from increased delivery of fatty acids to the liver, decreased export of fatty acids from the liver, or impaired oxidation of fatty acids within the liver. Insulin resistance is thought to play a key role in disease development by causing alterations in lipid metabolism, leading to increased uptake of fatty acids by the liver and increased oxidation of lipids within it.
Most patients remain asymptomatic, although nonspecific symptoms such as fatigue, malaise, and tenderness of the upper-right abdomen, may occur. In more serious cases, the pathologic features resemble those of alcoholic liver disease and may include fibrosis, inflammation, necrosis, and cirrhosis.
The progressive accumulation of triglycerides in hepatic tissue results from increased delivery of fatty acids to the liver, decreased export of fatty acids from the liver, or impaired oxidation of fatty acids within the liver. Insulin resistance is thought to play a key role in disease development by causing alterations in lipid metabolism, leading to increased uptake of fatty acids by the liver and increased oxidation of lipids within it.
Most patients remain asymptomatic, although nonspecific symptoms such as fatigue, malaise, and tenderness of the upper-right abdomen, may occur. In more serious cases, the pathologic features resemble those of alcoholic liver disease and may include fibrosis, inflammation, necrosis, and cirrhosis.
NON-ALCOHOLIC FATTY LIVER DISEASE RISK FACTOR
- Obesity, especially abdominal obesity.
- States of insulin resistance (typically related to obesity, diabetes mellitus, and the metabolic syndrome).
- Hyperlipidemia, especially hypertriglyceridemia.
- Severe or rapid weight loss.
- Total parenteral nutrition.
- Drugs (eg, glucocorticoids, synthetic estrogens, and certain pesticides).
- Pregnancy. Rarely, fatty liver occurs during pregnancy.
TREATMENT
Weight loss is essential for overweight patients with NAFLD. Even modest weight loss (-5% of body weight) may have significant beneficial effects by alleviating diabetes and hypertension.
Exercise may be beneficial, with or without associated weight loss. Use of pharmacologic weight loss agents may be beneficial, although this treatment has not yet been adequately studied. Morbidly obese patients (BMI>35 kg/m2) may consider surgical options, such as gastric bypass.
Diabetes mellitus in NAFLD patients should be treated as appropriate. Insulin-sensitizing drugs (eg, metformin, pioglitazone) may be especially useful and are also under investigation for use in nondiabetic patients with fatty liver, as they may reduce steatosis. Treatment of hyperlipidemia may decrease the progression of disease.
Weight loss is essential for overweight patients with NAFLD. Even modest weight loss (-5% of body weight) may have significant beneficial effects by alleviating diabetes and hypertension.
Exercise may be beneficial, with or without associated weight loss. Use of pharmacologic weight loss agents may be beneficial, although this treatment has not yet been adequately studied. Morbidly obese patients (BMI>35 kg/m2) may consider surgical options, such as gastric bypass.
Diabetes mellitus in NAFLD patients should be treated as appropriate. Insulin-sensitizing drugs (eg, metformin, pioglitazone) may be especially useful and are also under investigation for use in nondiabetic patients with fatty liver, as they may reduce steatosis. Treatment of hyperlipidemia may decrease the progression of disease.
NUTRITIONAL CONSIDERATIONS
Obesity, diabetes, and insulin resistance syndrome are implicated in the genesis of nonalcoholic fatty liver diseases. These conditions involve steatosis and oxidative stress, both of which can be modulated by diet. Preliminary research suggests that weight reduction on a low-fat, high fiber diet may be an effective treatment for NAFLD.
Weight Loss
Loss of excess weight may reduce the risk for developing NAFLD and effectively the hepatic steatosis and NASH. Compared with a rate of 20% in the general population, NAFLD affects up to 75% of obese individuals. Gradual, moderate weight loss (about 10% of body weight) usually reduces steatosis and may lead to improvement in liver function tests and histology. However, rapid weight loss exceeding about 1 lb per week in children and about 3.5 lbs per week in adults may result to necroinflammation, portal fibrosis, steatohepatitis, and bile stasis, along with worsening fibrosis.
Plant-based diets may be particularly helpful for both prevention and treatment of certain characteristic traits of NAFLD. Clinical trials have not yet evaluated the effect of low-fat, high-fiber vegetarian diets on NAFLD, as they have for cardiovascular disease and diabetes. However, these diets typically cause weight loss and can lower the concentrations of blood fats (eg, triglycerides) that contribute to nonalcoholic fatty liver disease. such diets are also associated with reduced insulin resistance, another precursor of NAFLD, and greater antioxidant protection, compared with omnivorous diets.
In addition, iron accumulation aggravates insulin resistance and oxidative stress. Plant-based diets have somewhat less iron bioavailability and vegetarians have lower body-iron stores.
Alcohol Avoidance
Alcohol intake strongly predicts blood triglyceride concentrations, and dyslipidemias (including elevated triglycerides) are present in a majority of individuals with nonalcoholic fatty liver disease. Some evidence indicates that steatosis correlates directly with alcohol intake. Consumption of more than 40 grams of alcohol per day doubles the risk of fatty liver and other liver diseases. Women may be affected at even lower levels of intake (eg, 20 to 30 g/d).
Obesity, diabetes, and insulin resistance syndrome are implicated in the genesis of nonalcoholic fatty liver diseases. These conditions involve steatosis and oxidative stress, both of which can be modulated by diet. Preliminary research suggests that weight reduction on a low-fat, high fiber diet may be an effective treatment for NAFLD.
Weight Loss
Loss of excess weight may reduce the risk for developing NAFLD and effectively the hepatic steatosis and NASH. Compared with a rate of 20% in the general population, NAFLD affects up to 75% of obese individuals. Gradual, moderate weight loss (about 10% of body weight) usually reduces steatosis and may lead to improvement in liver function tests and histology. However, rapid weight loss exceeding about 1 lb per week in children and about 3.5 lbs per week in adults may result to necroinflammation, portal fibrosis, steatohepatitis, and bile stasis, along with worsening fibrosis.
Plant-based diets may be particularly helpful for both prevention and treatment of certain characteristic traits of NAFLD. Clinical trials have not yet evaluated the effect of low-fat, high-fiber vegetarian diets on NAFLD, as they have for cardiovascular disease and diabetes. However, these diets typically cause weight loss and can lower the concentrations of blood fats (eg, triglycerides) that contribute to nonalcoholic fatty liver disease. such diets are also associated with reduced insulin resistance, another precursor of NAFLD, and greater antioxidant protection, compared with omnivorous diets.
In addition, iron accumulation aggravates insulin resistance and oxidative stress. Plant-based diets have somewhat less iron bioavailability and vegetarians have lower body-iron stores.
Alcohol Avoidance
Alcohol intake strongly predicts blood triglyceride concentrations, and dyslipidemias (including elevated triglycerides) are present in a majority of individuals with nonalcoholic fatty liver disease. Some evidence indicates that steatosis correlates directly with alcohol intake. Consumption of more than 40 grams of alcohol per day doubles the risk of fatty liver and other liver diseases. Women may be affected at even lower levels of intake (eg, 20 to 30 g/d).
Article Review
Vegetarian diet, food substitution and nonalcoholic fatty liver
Dietary interventions and strategies to optimize management of NFLD
Dietary interventions and strategies to optimize management of NFLD
Video Review
|
|
|
|
|
|
Unit Task
Submit your Reflective Journal after watching the videos, reading the lesson and article.