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Q: I’ve had non-alcoholic fatty liver disease (NAFLD) for about a year, but this is shocking: My 12-year-old son and my 19-year-old son both were recently diagnosed with it! How common is NAFLD, why does it develop, is it common for teens to have it, and are there simple things I can do, nutritionally speaking, to improve this condition?
—Fidela G., Los Angeles
A: Many people who hear the term fatty liver disease automatically think the condition only develops in people who drink too much alcohol. But non-alcoholic fatty liver disease (NAFLD) is spreading rapidly and is now the most common chronic liver disease in both children and adults in the United States.
NAFLD is a condition in which excess fat is stored in your liver. Added dietary sugar, particularly fructose, is implicated in contributing to the development of NAFLD, and avoiding added sugar is the main dietary strategy for treating the condition. A recent study found that overweight children with NAFLD sharply reduced the amount of fat and inflammation in their livers by cutting soft drinks, fruit juices, and foods with added sugars. Eating more vegetables and fruits and as many organic foods as possible are other beneficial strategies.
Non-alcoholic fatty liver disease facts
Between 30 and 40 percent of adults in the United States have NAFLD, according to the National Institute of Diabetes and Digestive and Kidney Diseases. Close to 10 percent of U.S. children ages 2–19 also have the condition, and it is more common in boys than girls. Research has demonstrated that NAFLD is also a growing problem among Millennials: In young adults, ages 18–35 years old, NAFLD has risen almost 2.5 times over three decades (from 9.6 percent in 1988–1994 to 24 percent in 2005–2010).
The condition is more common in people who are obese, and those who have type 2 diabetes or metabolic syndrome (which involves abdominal obesity, hypertension, elevated fasting blood sugar, high triglycerides, or low high-density lipoprotein [HDL] levels). It’s also associated with insulin resistance and high insulin levels even in lean people with normal blood sugar levels. While NAFLD occurs in people of all races, it is most frequently seen in Hispanics, followed by non-Hispanic whites.
Fatty liver disease typically has few symptoms, and many people who have it don’t know it. But the condition raises the risk of developing type 2 diabetes and heart disease, and it is associated with compromised reproductive health in both men and women. It can progress into a more severe liver condition called non-alcoholic steatohepatitis (NASH), which is a leading cause of liver cancer, cirrhosis, and liver transplants. About 3–12 percent of adults in the United States have NASH.
The Benefits of Switching to No Added Sugar
According to new research published in the Journal of the American Medical Association, avoiding foods and drinks with added sugars is an effective diet strategy for alleviating NAFLD, at least in teens. Researchers recruited 40 children with an average age of 13 who had fatty liver disease, and randomly assigned them to either a group that remained on their usual diets, or a group that limited added sugars.
Researchers asked the families of children on the limited-sugar diet to follow the diet too; they helped the families by swapping lower-sugar alternatives for foods that were typically consumed within the household in a typical week. For example, in place of yogurts, salad dressings, sauces, and breads that contained added sugar, the families were provided with versions of those foods that did not contain added sugar. Fruit juices, soft drinks, and other sweet drinks were forbidden.
After eight weeks, the low-sugar group had reduced their added sugar intake to just 1 percent of daily calories compared to 9 percent in the control group. The children with NAFLD in the low-sugar group had a 31 percent reduction in liver fat, on average, compared to no change in the control group. They also had a 40 percent drop in their levels of alanine aminotransferase, or ALT, a liver enzyme that rises when liver cells are damaged or inflamed. Although this study focused on diet therapy to improve fatty liver disease in children, other research suggests, and many holistic practitioners recommend, eliminating added sugar as a key strategy for anyone with NAFLD, no matter his or her age.
Other Recommendations for fight fatty liver disease
To further make food your best medicine for fighting NAFLD, try the following dietary recommendations, in addition to cutting out added sugar:
Eat More Vegetables and Fruits
Polyphenols, including quercetin, epigallocatechin gallate, anthocyanins, and resveratrol, which are found in fresh vegetables, fruits, plant extracts, and herbs, help prevent NAFLD by exerting lipid-lowering, antioxidant, anti-inflammatory, and antifibrotic properties. Therefore, consumption of fruits and vegetables rich in polyphenols is recommended to revent the development of NAFLD.
Good food sources of quercetin include onions, peppers, and asparagus. Epigallocatechin gallate is found in green tea. Berries and purple sweet potatoes are rich in anthocyanins, and resveratrol is found in grapes, blueberries, and cranberries.
One of the best ways to eat more veggies is to substitute them for grains. For example, have chicken and a double serving of non-starchy vegetables instead of a chicken sandwich on a bun.
Go Organic as Much as Possible
The liver not only plays an important role in the digestion, it also helps rid the body of toxins, including pesticides that are sprayed on conventionally produced foods. One pesticide of special concern is glyphosate-based Roundup. In a 2016 study, researchers concluded that even in “extremely low doses,” rats exposed to Roundup developed NAFLD over a two-year period. To reduce your exposure to pesticides and reduce the burden on your liver, look for foods that bear the USDA organic seal, which means they haven’t been sprayed with these noxious chemicals.
Milk Thistle: An Herbal Option to Help Treat Fatty Liver
Milk thistle is an herb known for its liver-protecting effects. Its active ingredient is silymarin, which has antioxidant properties. Some studies have found that silymarin, by itself or in combination with vitamin E, may help reduce insulin resistance, inflammation, and liver damage in people with non-alcoholic fatty liver disease. The dosages of milk thistle extract used in these studies were 250–376 mg per day. Medically speaking, silymarin is considered an option for treatment, especially in conjunction with a low-calorie diet and physical activity.