Non-alcoholic fatty liver disease (NAFLD) is the most common chronic liver disease in Canada and in other western countries.Sakramir/Getty Images/iStockphoto
You may not have heard of fatty liver disease, or non-alcoholic fatty liver disease to be specific. But chances are, you know someone who has it.
As a dietitian in private practice, it's becoming increasingly common for me to tailor diets for clients who've been diagnosed with a build-up of fat in their liver.
If your doctor has told you that you have a fatty liver, take action to reverse it. If left untreated, the condition can be more harmful than you think.
What is fatty liver disease?
Non-alcoholic fatty liver disease (NAFLD) is a progressive disease that develops in people who drink little or no alcohol.
It begins with its mildest form, simple fatty liver, an accumulation of fat in liver cells that, by itself, usually doesn't lead to liver damage.
However, a liver infiltrated with fat is more susceptible to further injury.
NAFLD can progress over time to a more severe form called non-alcoholic steatohepatitis (NASH), which is fatty liver accompanied by inflammation and death of liver cells. (Steato means fat and hepatitis means liver inflammation.)
About 15 per cent of people with NAFLD will go on to develop irreversible advanced liver scarring called cirrhosis, which makes it difficult for the liver to carry out its essential tasks.
NAFLD also increases the risk of developing heart disease, stroke and Type 2 diabetes.
Prevalence is growing fast
NAFLD is the most common chronic liver disease in Canada and in other western countries. It's estimated that one in five Canadians has NAFLD, a number that's escalating in conjunction with the increasing incidence of obesity and Type 2 diabetes. Many people don't even know they have a fatty liver.
Fatty liver disease isn't only an adult health problem, it's showing up in children, too.
According to the Canadian Liver Foundation, one in 10 Canadian children may have NAFLD. And the organization estimates that as many as 53 per cent of obese children have the condition.
What causes fatty liver?
The most common cause of NAFLD is obesity. It's estimated that 75 per cent of obese individuals are at risk of developing simple fatty liver and nearly one-quarter (23 per cent) are at risk for fatty liver with inflammation.
Having diabetes, high blood cholesterol and high triglycerides (blood fats) also increases the likelihood of developing fatty liver disease. Some people, though, don't have a clear predisposing cause.
The underlying mechanism for fat build-up in the liver is believed to be insulin resistance, often a consequence of obesity and excess belly fat. Insulin resistance means the body's cells are unable to use insulin properly. As a result, the body needs higher levels of insulin to clear sugar (glucose) from the bloodstream.
Do certain foods cause NAFLD?
A diet that's too high in fat contributes to excess fat stored in the liver. So does one that's high in refined carbohydrates and sugars. Liver cells convert excess glucose – the sugar that's absorbed into the bloodstream after digestion – into fat.
Fructose, in particular, is tied to fatty liver. Studies suggest that fructose consumption not only increases fat production in the liver, it also creates a metabolic environment that favours the development of NAFLD and NASH.
A study published last month in the Journal of Hepatology found that, among 271 children and teenagers with fatty liver disease, fructose consumption was significantly higher in children who had NASH compared with simple fatty liver.
Fructose is a simple sugar found naturally in fruits, some vegetables, honey, agave syrup and sucrose (table sugar). As high-fructose corn syrup ("glucose-fructose" on ingredient lists), it's also present in many soft drinks, sweetened fruit drinks, breakfast cereals, baked goods and condiments.
How do you know if you have a fatty liver?
Fatty liver rarely causes symptoms. When it does, symptoms are vague and may include right-sided abdominal pain, fatigue and/or a general feeling of unwellness.
NAFLD is usually detected when routine blood tests show elevated liver enzyme levels. It can also be discovered by an ultrasound examination of the abdomen.
How can you get rid of a fatty liver?
Lifestyle modification is the cornerstone to treating – and preventing – non-alcoholic fatty liver disease. Gradual weight loss, dietary modification and exercise are required to effectively remove fat deposits in the liver.
+++++++++
A diet plan for fatty liver disease:
Lose excess weight
Weight loss is the most effective treatment for NAFLD. A 5-per-cent weight loss can reduce liver fat deposits and a 10-per-cent loss is required to improve fatty liver with inflammation (NASH).
Lose weight gradually at a rate of one to two pounds a week. Rapid weight loss (four pounds a week or more) can worsen fatty liver.
Restrict refined grains
Limit your intake of high glycemic foods such as white breads and crackers, refined breakfast cereals and white rice. These foods spike glucose and insulin levels and may contribute to a fatty liver.
Choose fibre-rich whole grains such as brown rice, quinoa, whole wheat pasta, 100-per-cent whole grain breads and cereals and oatmeal, foods that raise blood glucose gradually, not quickly.
As a source of prebiotics (fibrous carbohydrates), whole grains also help feed beneficial gut bacteria. Some evidence suggests that an altered gut microbiome plays a role in fatty liver disease.
Don't overdo carbohydrates, though. A lower carbohydrate diet is beneficial for fatty liver disease.
Reduce sugars
Keep your intake of added sugars to no more than 5 per cent of daily calories, about 24 grams (6 teaspoons worth) for women and 36 grams (9 teaspoons worth) for men.
Avoid sugar-sweetened beverages, whether they're made with high-fructose corn syrup (fructose-glucose) or not.
Limit use of all caloric sweeteners including honey and agave syrup that are high in fructose. Read labels and, as much as possible, avoid foods sweetened with glucose-fructose.
Choose healthy fats
A diet that's lower in total fat and saturated (animal) fat will help improve fatty liver. Diets high in saturated fat have also been shown to induce insulin resistance.
Emphasize monounsaturated fat, the type found in olive oil, peanut oil, canola oil, avocado, almonds, cashews and pecans. Monounsaturated fat has been shown to increase fat breakdown and it may have anti-inflammatory benefits.
Eat fatty fish (e.g., salmon, trout, sardines) twice a week to get anti-inflammatory omega-3 fatty acids. If you have high blood triglycerides, speak to your dietitian or doctor about fish oil supplementation.
Boost antioxidant foods
Free radical damage, or oxidative stress, plays a key role in liver cell damage. Eat foods rich in dietary antioxidants such as citrus fruit, berries, mango, leafy green vegetables, carrots, sweet potato and nuts and seeds.
Avoid alcohol
If you have NAFLD or NASH, avoid drinking alcohol as it puts extra stress on your liver.
Increase exercise
Include at least 30 minutes of aerobic exercise five times a week and resistance training twice weekly. Doing so can improve fatty liver, lower blood sugar and reduce the risk of heart disease regardless of weight loss.
Leslie Beck