Nutrition Guide for Individuals w/Liver Disease-->可可转移

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GENERAL NUTRITIONAL GUIDELINES FOR INDIVIDUALS WITH LIVER DISEASE After being diagnosed with liver disease, among the first questions that patients typically ask concern nutrition. Unfortunately, one cannot expect to walk into the doctor's office and request "a diet for liver disease". Such an across-the-board diet simply does not exist. Many factors account for the unfeasibility of a standardized liver diet, including variations among the different types of liver disease (for example, alcoholic liver disease versus primary biliary cirrhosis) and the stage of the liver disease (for example, stable liver disease without much damage versus unstable decompensated cirrhosis, complicated by encephalopathy). Other medical disorders unrelated to liver disease, such as diabetes or heart disease, must also be factored into any diet. Each person has his or her own individual nutritional requirements, and these requirements may change over time. Nutrition and liver disease can be a complicated subject. That is why I devoted an entire chapter to this topic in my book: "Dr. Melissa Palmer's Guide To Hepatitis And Liver Disease". The following information, which is excerpted from my book, contains just a few highlights that an individual should keep in mind nutritionally. Notwithstanding the above information, an example of an optimal diet for a person with stable liver disease (modifications to be made as per individual needs) might contain all of the factors listed below. 1) 60 - 70 percent carbohydrates - primarily complex carbohydrates, such as pasta and whole-grain breads. 2) 20-30 percent protein - only lean animal protein and/or vegetable protein. 3) 10 - 20 percent polyunsaturated fat. 4) 8-12 eight ounce glasses of water per day. 5) 1,000 to 1500 milligrams of sodium per day. 6) Avoidance of excessive amounts of vitamins and minerals, especially vitamin A, vitamin B3, and iron. 7) No alcohol. 8) Avoidance of processed food. 9) Liberal consumption of fresh organic fruits and vegetables. 10) Avoidance of excessive caffeine consumption - no more than 1-3 cups of caffeine-containing beverages per day. 11) Vitamin D and calcium supplement. PROTEIN Proteins are the major building blocks that the body uses to make body components such as muscles, hair, nails, skin, and blood. Proteins also make up important parts of the immune system called antibodies, which help fight off disease. Since protein is such a vital component of the body, many people mistakenly believe that the more protein they consume, the better. Not only is this belief misguided, but also for someone with liver damage such an approach to nutrition can actually be downright dangerous. The trouble is that a damaged liver cannot process as much healthy liver. And, when a damaged liver gets unduly overloaded with protein, encephalopathy (a state of mental confusion that can lead to coma) may occur. Finally, diets high in protein have been demonstrated to enhance the activity of the cytochrome P450 enzyme system, which is responsible for drug metabolism. This enhanced activity increases the likelihood that a drug may be converted into a toxic byproduct capable of causing liver injury. Protein intake must be adjusted in accordance with a person's body weight and the degree of liver damage present. Approximately 0.8 grams of protein per kilogram (2.2 pounds) of body weight is recommended in the diet each day for someone with stable liver disease. People with unstable liver disease or decompensated cirrhosis need to lower the percentage of protein content in their diets so that it falls between approximately 10 to 15 %. And, they need to eat only vegetable sources of protein. A diet high in animal protein (which typically contains a lot of ammonia) may precipitate an episode of encephalopathy among these people. Vegetarian diets, on the other hand, have a low ammonia content and have been shown to be much less likely than animal protein diets to induce encephalopathy. It is important to keep in mind that some popular weight-loss diets involve the consumption of a very high animal protein content. People with cirrhosis are advised to avoid any such diets. CARBOHYDRATES The major function of carbohydrates is to provide a ready supply of energy to the body. The liver plays a crucial role in carbohydrate metabolism. Before sugars are able to supply energy to the body, they are routed to the liver, which is in charge of deciding their fate. Thus, it may immediately send sugar into the blood stream to provide an instant energy boost. Or, the liver may send glucose to the brain or muscles, depending upon what activities are being performed at the time, (for example, taking a test versus exercising). Or it may decide to store glucose (in the form of the starch glycogen) for later use. Converting foods other than carbohydrates into energy is stressful, even to a normal liver. By eating an unbalanced diet that is low in complex carbohydrates, a person with liver disease will add to the stress that the disease has already caused the liver. In fact, this is one reason why so many people with liver disease feel fatigued. Simply put, their diets are working against them. People with liver disease should strive for a diet consisting of approximately 60 - 70 % carbohydrates, with complex carbohydrates (starches and fibers) predominating. A well-balanced diet will include at least 400 grams of carbohydrates. If there are too few carbohydrates in a person's diet, this will likely result in excessive protein and fat intake. FAT Fats are the body's most efficient means for storing excess energy. Gram for gram, fats contain more than double the amount of calories of other nutrients. That is why a diet high in fat is likely to result in more weight gain than a diet high in calories from protein or carbohydrates. It is important for people with liver disease to minimize their fat intake by avoiding foods that are high in fat content. Excess fat can result in a fatty liver or nonalcoholic steatohepatitis (NASH). Not only can a fatty liver cause liver disease, it may contribute to the worsening of other liver diseases. For example, it has been demonstrated that people with hepatitis C and a fatty liver are likely to develop scarring in the liver at an accelerated rate. Furthermore, although uncommon, it is possible for someone with NASH to develop cirrhosis and liver failure. In fact, fatty livers are felt to be so unhealthy that they are not even considered viable for use in transplantation. As a general rule, no more than 30% of a person's caloric intake should come from fat. People who are overweight should aim for something in the neighborhood of 10%. While it is important to eat as little fat as possible, eating a small amount of the more healthy fats does have some benefit. For example, people need some fat in order to properly absorb the four fat-soluble vitamins - A, D, E, and K. Without some fat, these vitamins may become deficient in the body, even if they are taken in supplemental form. This type of vitamin deficiency sometimes occurs in people with cholestatic diseases such as primary biliary cirrhosis. VITAMINS AND MINERALS The liver is the body's main warehouse for storing nutrients. It absorbs and stores excess vitamins and minerals from the blood. If a person's diet does not supply an adequate amount of these nutrients on a given day, the liver releases just the right amount of them into the bloodstream. However, the liver has only a limited capacity for processing vitamins and minerals. Any excess amounts that the liver is unable to process are generally eliminated from the body. Yet, at some point, the liver can become damaged due to the strain of processing an overabundance of certain vitamins and minerals (particularly iron, vitamin A and niacin). If a person eats a healthy, well-balanced diet, all the vitamins and minerals for daily needs and activities should be amply supplied. Despite this, many people feel that they should take vitamin and/or mineral supplements "just to be on the safe side". While this may be fine for an overall healthy person, it may be downright dangerous for someone with liver disease. Thus, excessive doses of vitamin and mineral supplements may do much more harm than good to an already damaged liver. However, there are exceptions to this rule. First, not everyone eats a healthy well-balanced diet. Also, some people follow strict vegetarian diets. Under these circumstances, vitamin and mineral supplementation may be necessary. People with certain liver diseases, especially cholestatic diseases, such as primary biliary cirrhosis, absorb some vitamins poorly. Thus, these people may also require supplementation. Moreover, people with alcoholic liver disease have a need for vitamin supplementation due to the nutrient-depleting effects of alcohol on the body. On the other hand, some liver diseases actually result in an overload of a certain vitamin or mineral. An example of this is hemochromatosis, which is a liver disease of iron overload. Alternatively, there are liver diseases that may be associated with iron deficiency. This may be due to internal bleeding, which can occur in people with bleeding esophageal varices due to decompensated cirrhosis. Therefore, the requirements of vitamins and mineral in the diet of a person with liver disease must be evaluated on an individualized basis. An in-depth review of every vitamin and mineral is beyond the scope of this article, and the reader is referred to my book for a detailed discussion. However, in general it is important to keep in mind that excessive doses of iron, vitamin A and niacin have been found to be toxic to the liver. Thus, individuals with liver disease are generally advised to avoid these supplements. And, since osteoporosis (a disease characterized by reduced bone mass resulting in an increased risk for bone fractures), is common to many liver diseases, it is a good idea for all people with chronic liver disease to take a calcium supplement. Calcium supplementation should be limited to no more than 1000 to 2000 milligrams per day and should be taken with a vitamin D supplement (which is usually included in the calcium tablet). Since stomach acid is needed to properly absorb calcium, antacids, such as Tums, which reduce stomach acid, are poor sources of calcium. Finally. Individuals suffering from ascites- a complication of cirrhosis resulting in an abnormal accumulation of fluid in the abdomen need to limit their intake of sodium. For every gram of sodium consumed, the accumulation of 200 milliliters of fluid results. The lower the consumption of sodium in the diet, the better controlled this excessive fluid accumulation is. For people with ascites, sodium intake should be restricted to less than 1,000 milligrams per day and preferably under 500 milligrams. This goal is difficult, yet attainable. SOME TIPS ON DIET Dining out can present a challenging situation for a person on a special or restricted diet. The fat, sodium, and calorie content of restaurant foods are not included on the menu. For this reason, it is best to steer clear of fast-food establishments completely. When dining out, food should be ordered cooked "dry", meaning it should be prepared without butter, margarine, or oil. Most people with liver disease find that eating multiple small meals throughout the day is the best approach, as it maximizes energy levels and the ability to digest and absorb food. Finally, it must be stressed that all alcohol consumption should be avoided. This includes hidden alcohol contained in desserts, especially cakes and certain coffees. -Melissa Palmer, MD “Dr. Melissa Palmer's Guide To Hepatitis And Liver Disease”