Informed Patient Conference 2006
June 10-11, 2006, Stanford California
Healthy Nutrition, Healthy Liver
Ms. Patsy Obayashi, MS, RD, CDE, Transplant Nutrition Specialist, Stanford University Medical Center
Why is your liver so important? Because you can’t “live” without it!
Protein helps build and repair muscle, and maintain fluid balance. It provides 8 essential amino acids found either in meat (a complete source of all 8 amino acids) or plants (an incomplete source; therefore, must be combined with other food sources to obtain all 8 amino acids).
- 1 gram protein = 4 calories (e.g. 1 ounce of meat = 7 grams of protein)
- Protein needs are based on lean or dry body mass (formula = 0.8 gram protein/kg body weight)
For example, a 125 pound person = 56.8 kg; then multiply 56.8 kg x 0.8 = 45 grams protein needed
- Is protein bad? No, it is essential. Too little can cause problems if the liver is compromised (e.g. hepatitis B); and too much can increase the workload of the liver.
(or glycemic control and the liver)
Glucose is the end-product in the digestion of carbohydrates. Glucose is the primary source of energy for muscles and the brain. The liver stores, releases and makes glucose in four different ways:
- glucogenesis (creation of glucose from non-carbohydrate sources)
- glycolysis (conversion of glucose into energy)
- glycogenesis (creation of glycogen from glucose)
- glycogenolysis (release of glycogen)
Advanced liver disease interferes with this function, which can cause poorly controlled glucose (blood sugar) fluctuations.
- 1 gram carbohydrates = 4 calories (which is the same for protein)
- Carbohydrates are meant to be burned, to be used an energy source; however, protein is not meant to be burned because it is for building and repairing the body.
How many carbohydrates do we need? Approximately 40-50% of our total calories should come from carbs. Too few carbs forces our body to burn protein and fat for fuel, which isn’t good. For example, an 1800 calorie diet includes 225 grams of carbohydrates/day (the goal is then 15 servings of 15 grams of carbohydrates each day).
Fats are used as a long-lasting fuel. The liver is involved because it makes bile, which the gallbladder then releases to help break down fats during digestion (high fat diets can over-stimulate the gallbladder). The liver also utilizes fats to make cholesterol, which is then carried through the blood in “lipoproteins”.
- High-density lipoproteins (HDL) = “good” cholesterol; want these to be high
- Low-density lipoproteins (LD) = “bad” cholesterol; want these to be low
Remember, HDL should be High, LDL should be Low. High density lipoproteins are good because they help mop up excess cholesterol in the bloodstream (regular exercise helps to increase HDLs).
There are Saturated Fats (solid at room temperature) and Mono or Poly-Unsaturated Fats (liquid at room temperature). The saturated fats are from meat sources and are much more harmful than the mono (from plant sources) and poly-unsaturated fats.
Omega 3 fatty acids are a subclass of poly-unsaturated fat that help prevent platelets from sticking to blood vessels (sticking causes clotting), which can decrease the risk of clogged arteries. Examples of this type of fat include soybean oil or fatty fishes.
Hepatitis, though, can result in reduced clotting ability. Therefore, omega 3 fatty acids may need to be avoided to prevent further problems. In addition, hepatitis may affect the production and management of cholesterol, so these levels may need to be monitored more carefully.
Vitamins and Minerals
Fat Soluble Vitamins are stored in the liver. Toxic levels of these vitamins can build up if the liver is damaged (i.e. hepatitis B).
- Vitamin A – keeps skin and eyes healthy
- Vitamin D – builds bones
- Vitamin K – helps with clotting
- Vitamin E – an oxidant, but is not stored in the liver
Water Soluble Vitamins are excreted in urine if excess levels are reached.
- Vitamin C – boosts the immune system
- B Vitamins
Trace Elements are components of enzymes stored in the liver, muscles, bones and other organs.
- Selenium – an anti-oxidant; stored in the liver and kidney (high amounts can be toxic)
- Zinc – need for wound healing, immunity, healthy appetite; a deficiency found in cirrhosis, diabetes, and those taking diuretics; high fiber diets may interfere with zinc absorption
Hemochromatosis is a liver disease with increased iron levels; therefore, these patients must avoid high iron foods and avoid cooking with iron skillets, etc. For hepatitis patients without hemochromatosis, then iron-rich foods should not be avoided because the other dietary benefits from these foods will be lost.
Fluids and Water
Everyone needs 8 cups of fluid each day. Although water is probably best and doesn’t have any calories, fluids are fluids. Although there are interesting studies about the benefits of coffee on liver disease, they are based on observation, not controlled studies.
How to evaluate a research article
Ask the following questions as you read a research article in order to decide how credible it is:
- How was the study done? Was it randomized, controlled, or observational?
- Was it a human study or an animal study?
- What was the size and duration of the study? For example, 5 people over two weeks vs. 1000 people over three years? More people over longer periods of time usually provide better information.
- What was the specific condition or application of the study? For example, viral hepatitis or hepatitis B?
- What is the reputation and source of the research? Was it an NIH study or an individual reporting results?
- What is the source of funding for the study? Was it the NIH or a pharmaceutical company funding the research?
Herbal supplements are not FDA regulated, therefore you must be careful. Some herbs could interact negatively with prescribed drugs or foods (remember, the liver metabolizes almost everything we eat or swallow). If you decide to take herbal supplements, tell your doctor and make sure you buy from a reputable source. There are not a lot of well controlled studies on herbal supplements in the United States.
- Alpha lipoic acid – animal studies; some protection
- SAMe – animal studies; claims to help with depression
- Green tea extract – animal studies show it protects against alcohol damage in rats
- Celery seed, turmeric, dandelion, licorice root – need more controlled studies; certainly OK to use in the preparation of food; will also get other nutritional benefits from cooking with the actual herb
- Milk Thistle – human studies done; most studied herb in U.S.; generally considered OK but still need to be careful about possible interactions with other drugs.
General recommendations on how much you need to keep your liver healthy
- Calories – 25 to 35 calories/kilogram of lean body mass
- Protein – 1.2 to 1.5 grams protein/kilogram of lean body mass
- Carbs – 45 to 50% of total calories
- Fat – 30% of total calories
- Water-soluble vitamins – one generic multi-vitamin a day is OK; but if you’re eating 5 servings of fruit, vegetables and whole grains each day, then you probably don’t need a vitamin supplement.
- Fat-soluble vitamins – take in a “water-soluble” form if you have a liver problem
- Minerals – only take a supplement if you have a known deficiency
- Fluids – doesn’t have to be just water
- Exercise – 30 to 45 minutes physical activity a day for maintenance (60-90 minutes for weight loss)
For example : A 125 pound person needs each day about 1,400-2,000 calories, 68-85 grams protein, 175-250 carbohydrates, 50-70 grams fat, and 1400-2000 ml of fluids (6-8 cups)
Please remember, however, these are general guidelines for relatively healthy adults.
For hepatitis patients, moderation is the key. Eating right, taking care of yourself, and exercising are good things to do. More specific recommendations are available for severe liver disease such as cirrhosis and liver failure, where proteins, fluids, etc. are critical medical issues.
Take home message
Nutrition is a valuable tool, a “medicine” that YOU can directly control to stay as healthy as possible, to help your liver as much as possible! Normal, basic healthy nutrition habits will help most livers. Once there is more serious liver damage, then specific dietary recommendations can be made.
Other Nutrition Information Resources