by Christi Bowling, MS, RDN, CSSD, LD
At MetaPhy Health, one of the most common diagnoses encountered in our patient population is Fatty Liver Disease, which includes Non-Alcoholic Fatty Liver Disease (NAFLD) and Non-Alcoholic Steatohepatitis (NASH). Thirty-four percent of adults in the U.S. have NAFLD, and individuals with the disease have a higher risk of all causes of mortality. Most patients who have a fatty liver also have excess body weight, and in fact, obesity is a common and well-documented risk factor for NAFLD, as well as a predictor of advanced disease.
The current standard of care for treating patients with NAFLD focuses on lifestyle interventions, particularly diet and exercise. Aside from weight gain and obesity, dietary composition can influence the development of NAFLD, so the Telehealth Care Coordinators (TCCs) at MetaPhy utilize current recognized recommendations for medical nutrition therapy provided by our Registered Dietitian Nutritionist for NAFLD treatment.
A higher dietary intake of saturated and trans fatty acids is associated with liver inflammation and NAFLD, which is why our TCCs emphasize a reduction of these specific fats to our Fatty Liver patients. This includes limiting foods such as red meat, full-fat cheeses, most fast foods, fried foods, desserts, heavy sauces, butter, and creamy dressings. A recent study found that high consumption of red and/or processed meats is associated with NAFLD. Limiting the consumption of unhealthy types of meat and improving preparation methods (avoiding frying or over-grilling meat until charred) may also be considered part of the NAFLD lifestyle treatment. The unsaturated or “healthy fats” that we emphasize are from sources such as nuts and seeds, fatty fish, olive and vegetable oils, and avocados. In two small randomized trials, patients following the Mediterranean diet, which is higher in healthy fats like olive oil and omega-3s from both plant and marine sources, experienced a 29% to 38% reduction in liver fat and improved insulin sensitivity compared with those following an individualized low-calorie, low-fat/high-carbohydrate diet.
Findings from diabetes literature and available NAFLD data state that the amount and type of carbohydrates in the diet likely have an important impact on NAFLD.NASH patients have been found to consume more sweets and simple carbohydrates, including fructose and high fructose corn syrup (aka refined carbohydrates). Researchers have hypothesized that fructose can be linked to NAFLD through both indirect and direct mechanisms, including weight gain and increased insulin circulation.
Our TCCs emphasize reduction of these refined carbohydrates such as white rice, white bread, and products made from refined flour, refined sugar, sugary drinks, and desserts. Recommended carbohydrates include high fiber choices such as beans, brown rice, quinoa, products made with whole grains, and sweet potatoes. These high fiber, complex carbohydrates increase satiety, improve insulin sensitivity, and can aid in weight loss, which can in turn improve NAFLD.
The liver breaks down most of the alcohol you drink so that it can be removed from your body, but that process can generate harmful byproducts. These substances can damage liver cells, promote inflammation, and weaken your body’s natural defenses. The more alcohol that you drink, the more you damage your liver. It is recommended by our TCCs that alcohol be avoided in the diet as much as possible.
Physical activity can help maintain weight loss and improve insulin resistance, and recent data suggests that patients who demonstrate fatty liver improvement tend to be more active. Improvement in insulin sensitivity has also been shown to correlate with a reduction in total body fat, which in turn contributes to the fatty acid delivery to the liver. As a result, a physical activity intervention leads to improvement in insulin resistance and may decrease inflammation and disease progression of NAFLD. A good starting point is to incorporate 30 minutes of activity three times a week with the ultimate goal of 30 minutes of activity five times a week, as recommended by the American College of Sports Medicine.
Lifestyle modification through diet and exercise must be the first-line therapy of any treatment plan for patients with NAFLD. Available studies suggest that weight loss of 5% or more improves steatosis, and weight loss of 7% or more improves disease activity. Following a Mediterranean diet can reduce liver fat even without weight loss and is the most recommended dietary pattern for NAFLD. The Mediterranean diet is characterized by reduced carbohydrate intake, especially sugars and refined carbohydrates, increased monounsaturated and omega-3 fatty acid intake, and increased fresh foods such as fruits, vegetables, and lean proteins. Weight loss, physical exercise, and dietary changes should be implemented on a long-term basis for all patients with NAFLD/NASH, regardless of disease severity, in order to help reduce liver fat and inflammation.
Christi Bowling is the Director of Nutrition Services for MetaPhy Health. Every quarter she provides her unique perspective and valuable expertise on all things diet and nutrition relative to chronic disease management.
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