Fatty fish, such as tuna, contain high amounts of omega-3 fatty acids. These may reduce inflammation and fat accumulation in liver cells in people with non-alcohol-related fatty liver disease (NAFLD).

Many people refer to this health condition by an older name: nonalcoholic fatty liver disease.

Weight loss, through a combination of exercise and dietary modifications, remains the first line of treatment. It can help reverse NAFLD or keep it from progressing.

A person’s diet can affect their liver health. Some people may wonder whether fatty fish may benefit NAFLD.

Below, learn more about NAFLD, its management techniques, and whether raw tuna may help.

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This term refers to a group of conditions that cause excess fat to accumulate in the liver.

The buildup of fat can injure the liver, leading to permanent scarring and irreversible damage to liver cells. These effects are called cirrhosis. Cirrhosis may lead to liver failure and liver cancer.

People who are more likely to have NAFLD include those with:

Sometimes, heavy alcohol use can cause alcohol-associated liver disease. By contrast, people with NAFLD may drink little or no alcohol. There are two types of NAFLD:

Older research suggests that raw tuna is a good source of many nutrients, including selenium and anti-inflammatory omega-3 polyunsaturated fatty acids (PUFAs).

However, eating raw fish comes with health risks. And some types of cooking retain more nutrients than others. A person might consider speaking with a doctor or registered dietitian for advice.

Tuna contains healthy fats, including the omega-3 fats docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA). Most of these fats contain omega-3 fatty acids, which fish synthesize from their consumption of marine plants.

Other fish that are rich in omega-3 fatty acids include:

No significant evidence suggests that raw tuna can improve NAFLD. Fish oil supplements are a more concentrated source of EPA and DHA, and so may be helpful.

Fish oil contains omega-3 PUFAs. The main types of these acids are:

  • alpha-linolenic acid
  • DHA
  • EHA

Fish oil may protect against harmful effects of a high fat and high cholesterol diet. A 2015 study on the dietary treatment of NAFLD listed the following health benefits of consuming oily fish and fish oil:

A 2018 study found that omega-3 long-chain PUFA supplementation led to significant improvements in people with NAFLD.

The improvements concerned:

  • liver enzyme levels
  • liver fat contents
  • measures of hepatic steatosis
  • metabolic risk factors

A 2020 review supported the findings above. It also suggested that omega-3 long-chain PUFA supplementation improves levels of fat in the liver, as demonstrated by a reduction in body mass index scores among people with NAFLD.

In a 2021 study, people with NAFLD and type 2 diabetes took 2000 milligrams of omega-3s every day for 12 weeks. The researchers found significant improvements in the participants’ fatty liver index, lipid accumulation product, and visceral adiposity index scores, compared with those of participants who had received a placebo.

Weight loss is key for managing NAFLD. But rapid, significant weight loss may induce liver dysfunction and inflammation. Instead, the best approach is to lose weight through regular exercise and a low-calorie diet that includes healthy foods.

A healthcare professional may recommend that a person with NAFLD loses 7–10% of their body weight.

A 2021 review recommends that people with NAFLD focus on eating whole, nutrient-dense foods. These are rich in proteins, complex carbohydrates, and unsaturated fats and include, for example:

People with NAFLD should limit:

A registered dietitian or a doctor can help create a diet plan that allows a person to reach their health goals.

The Mediterranean diet, in particular, may benefit people NAFLD by improving liver fat levels.

Exercise may help:

Regular exercise might involve:

  • walking
  • gardening
  • light jogging
  • housework

However, a 2020 study found that moderate-intensity physical activity led to more significant improvements in NAFLD than low-intensity physical activity.

Exercising on its own may improve NAFLD and glucose tolerance. However, diet and lifestyle changes are usually necessary.

The Centers for Disease Control and Prevention (CDC) recommend that adults get at least 150 minutes of moderate-intensity physical activity each week. A person may need more or less than this, depending on their health status and goals.

NAFLD is caused by fat building up in the liver, potentially causing inflammation and liver damage.

Raw tuna and other oily fish contain high amounts of omega-3 fatty acids. These may reduce inflammation and the amount of liver fat. They may also prevent further liver damage.

A healthy diet and regular exercise are the best ways to manage and prevent liver damage that stems from NAFLD. A registered dietician or a doctor can help a person tailor a dietary plan that helps them reach their weight loss goals safely. A doctor or dietitian can also advise about whether it is safe to eat raw tuna.