Nonalcoholic steatohepatitis (NASH) is a progressive form of nonalcoholic fatty liver disease (NAFLD). Dietary changes can slow the progression of NASH and prevent lasting liver damage.

There are no approved drug treatments for NASH. Methods of managing the condition include lifestyle and diet changes, including eating a nutritious diet rich in a variety of plant foods.

A NASH-friendly diet will also limit or cut out certain types of foods, such as animal products and processed foods.

Having NASH indicates a person has excess fat and inflammation in their liver that can cause liver scarring, or fibrosis. As scar tissue accumulates in the liver, it may affect its functioning, and without treatment, this scarring can lead to cirrhosis and liver failure. A suitable liver diet for NASH may prevent or reduce further damage in someone with the condition.

Keep reading to learn more about the NASH diet, including foods to eat, foods to avoid, and other lifestyle changes that can benefit people experiencing the condition.

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A healthy NASH diet focuses on making changes to the diet by including various nutritious foods.

The program may seem restrictive at first and require significant changes in some people’s daily eating patterns. However, a nutritious NASH diet still allows for a range of foods.

Vegetables

Vegetables are essential for overall health. Regularly eating a wide array of vegetables helps ensure the body gets plenty of nutrients and vitamins. Adults should get around 2–4 cups of vegetables per day, depending on their sex and age.

Some examples of vegetable groups include:

  • dark, leafy greens, such as kale, mustard greens, and spinach
  • root vegetables, such as yams, turnips, and beets
  • legumes, including beans, peas, and lentils
  • cruciferous vegetables, such as Brussel sprouts, cabbage, and broccoli
  • alliums, such as onion, garlic, and leeks
  • stem vegetables, such as celery, asparagus, and fennel

There are many vegetables to include in the diet. It may be most important to find a wide variety and eat enough vegetables each day.

Fruits

Fruits can be a part of a NASH diet in moderation. Whole fruits can provide many nutrients and vitamins to the body and make for a suitable snack or dessert.

Fruits may include:

  • citrus fruits, such as lemon, orange, and grapefruit
  • stone fruits, such as apricots, peaches, and plums
  • berries, including raspberries, blueberries, and blackberries
  • melons, such as watermelon and canteloupe
  • tropical fruits, such as pineapple, banana, and papaya

Whole grains

Whole grain options may provide an alternative to processed, refined grains that are rich in fiber and nutrients.

Whole grains or alternatives include:

  • wheat
  • brown rice
  • barley
  • oatmeal
  • corn
  • buckwheat
  • quinoa

Good protein sources

A NASH diet will also include suitable protein sources. Some protein options that may fit into a healthy liver diet include:

  • fatty fish, such as cod, sardines, and salmon
  • cooked shellfish, such as shrimp, crab, and lobster
  • lean poultry, such as chicken or turkey
  • trimmed, lean red meat options, such as trimmed loin, round, or sirloin
  • eggs
  • legumes and beans, such as soy products, lentils, or chickpeas
  • nuts, such as almond, cashew, or peanuts

Healthy fats

A healthy diet will still have room for fats but will focus on replacing saturated and trans fats with more nutritious, unsaturated fats.

Examples of nutritious fat sources include:

  • walnuts
  • seeds, such as chia and flax
  • extra virgin olive oil
  • olives
  • avocados
  • fatty fish, such as sardines, herring, and salmon

Diet programs

Few diets follow many of the tenants of healthy eating. However, with little modification, some eating programs may be easier to adapt than trying to create a new plan.

Some diet types that may follow a similar nutritious eating pattern as a NASH diet include low carbohydrate diets that limit added sugars and refined carbs. In addition, low fat diets that limit trans and saturated fats might also be suitable.

A NASH diet will also focus on making changes to the diet by excluding or limiting some foods, including the below.

Sugary foods

High sugar foods may be a significant source of calories with little nutritional value for many people.

Many sugary foods also contain fructose, a fruit sugar that the liver processes during digestion.

The body also breaks down other sugars, such as sucrose or table sugar, into glucose and fructose during digestion, meaning sugar is another source of fructose.

Research from 2021 that fructose in the diet stimulates the body to make more fat and contributes to insulin resistance. It also states that fructose consumption is a possible major dietary risk factor for NAFLD.

Examples of sugary foods to limit or avoid include:

  • sugar-sweetened beverages, such as soda, fruit juice, and fruit cocktails
  • jams and jellies sweetened with sugars
  • baked goods or packaged foods with added sugars
  • candy and other sweets
  • ice cream
  • sauces and condiments containing added sugars

Refined or processed carbohydrates

Processed carbohydrates may cause similar increases in sugars in the body after digestion. An appropriate diet for NASH may limit or avoid refined, or processed carbohydrates, such as:

  • white bread
  • white rice
  • starches and starchy foods
  • commonly fried foods, such as french fries, potato chips, and onion rings

Fatty foods

Doctors may also recommend eliminating foods high in saturated fats, trans fats, or hydrogenated oils.

The National Institute of Diabetes and Digestive and Kidney Diseases states that these fats are a source of high calories that increase the chances of obesity. Non-nutritious fats may also increase the risk of conditions such as heart disease. Both of these conditions are risk factors for NAFLD and NASH.

There are several dietary sources of these fats to avoid, and doctors may recommend eliminating or drastically reducing sources, including:

  • fatty red meats, such as beef, lamb, and pork
  • deli meats, such as potted meat, cold cuts, and packaged sausages
  • baked goods, cookies, and cakes
  • packaged foods containing saturated fats and hydrogenated oils
  • full fat dairy, ice cream, and yogurt

Doctors may also recommend limiting or adding other foods depending on the person’s risk factors. This may include:

  • limiting sodium intake
  • eliminating alcohol intake
  • eliminating dietary supplements that may affect the liver
  • adding coffee to the diet
  • adding green tea to the diet
  • adding a variety of spices to the diet

A suitable NASH diet is one of several beneficial changes to help protect and reduce damage to the liver. Doctors will also recommend other lifestyle changes for a healthy body, including:

Regular aerobic exercise

Active exercise that raises the heart rate is beneficial for overall health and may help burn calories and maintain a moderate weight.

Getting about 150 minutes of activity that raises the heart rate each week may be enough for most. This consists of around 30 minutes each day of activities such as:

  • brisk walking
  • gardening
  • weight lifting
  • jogging
  • bicycle riding
  • swimming
  • martial arts

Maintaining a moderate weight

Maintaining a moderate weight is a key step to treating NAFLD and NASH.

Research from 2018 notes that losing at least 3–5% of a person’s body weight can reduce fat in their liver. Larger increases, from about 7–10% of an individual’s total body weight, may also help reduce inflammation and scarring from NASH.

Other factors

Controlling other factors is an important part of treating or preventing NASH. This may include:

  • controlling diabetes
  • keeping the cholesterol in healthy ranges
  • avoiding alcohol
  • avoiding smoking
  • only using over-the-counter medications that may affect the liver under the guidance of a doctor
  • speaking with a healthcare professional before taking any supplements
  • considering vaccinations for diseases that may affect the liver, such as hepatitis

Anyone with concerns about their metabolic health should consult a doctor. In some cases, NAFLD and NASH will show no symptoms, making regular checkups and screenings an important part of prevention.

Anyone who has NAFLD or NASH should work with their doctor to discuss treatment options. They may refer the person to a dietitian to devise a meal plan or decide which foods they can eliminate from their diet and recommend alternatives.

Dietary changes can prevent lasting liver damage and slow the progression of nonalcoholic steatohepatitis (NASH), a progressive form of nonalcoholic fatty liver disease (NAFLD).

People with NASH tend to have fat accumulation and inflammation in their liver, which can cause damage to the organ, in the form of scarring, or fibrosis.

Eating more fruit, vegetables, and grains are vital dietary changes for people with NASH. Avoiding or limiting sugary foods, fatty foods, and refined carbohydrates are also beneficial in slowing the condition’s progress.

Getting regular exercise and maintaining a moderate weight are also advisable for those with NASH.