The Essential Value of Exercise in NAFLD

Woman Walking Her DogNAFLD – the accumulation of fat in the liver without excessive alcohol use – is one of the key reasons that obesity is a real and chronic disease. It is one of the common complications of obesity, and it is rising in parallel with obesity – most disturbingly in children. Of course, losing weight is an effective way to reduce fat in the liver. But a new systematic review and meta-analysis tells us that exercise has an essential value for NAFLD, independent from weight loss.

In fact, 150 minutes of moderately intense physical activity weekly more than triples the odds for significantly reducing liver fat. In other words, five brisk 30-minute walks each week is enough. It can make a big difference in liver health for people with NAFLD – whether or not they lose weight.

A Compelling Analysis

Jonathan Sine and colleagues offer us a compelling analysis with their new study  in the American Journal of Gastroenterology. They found data from 14 studies with a total of 551 persons that met criteria for inclusion in their meta-analysis. In that analysis they found that an exercise dose of 750 metabolic equivalents (METS) per week raised the odds of a clinically significant reduction in liver fat by a factor of 3.51. That exercise dose equals five brisk 30-minute walks per week.

The definition of a clinically significant reduction in liver fat is 30 percent. That amount of fat reduction has been shown to be a good surrogate for improvement in the pathology of NAFLD, including inflammation and fibrosis in the liver.

A Rising Problem

NAFLD is rising because of the persistent rise in obesity prevalence. Recently in Obesity, Aaron Slusher and colleagues documented a large rise in NAFLD among patients in the Yale Pediatric Obesity Clinic. It coincided with the COVID pandemic, which also appears to have prompted a spike in pediatric obesity. Prior to the pandemic, 37 percent of the patients in the clinic also had NAFLD. During the pandemic, that number rose to 61 percent

NAFLD can progress to liver inflammation, fibrosis, liver cancer, liver failure, and death. So it deserves serious attention, but it often goes undetected.

Good News for Patients

The bottom line here is good news for people who are living with NAFLD. Because they have a rather simple tool for improving the health of their liver available to them – exercise. UCLA Assistant Professor Ani Kardashian sums it up nicely:

“My message to my patients is going to be that regular exercise can have a very positive effect on the liver. Even if you’re struggling with weight loss, it can still lead to the amount of fat in the liver going down or being reduced.”

Enjoy a brisk walk five days a week and you can more than triple your odds for better liver health.

Click here for the study by Stine et al, here and here for further reporting on it.

Woman Walking Her Dog, painting by Vincent van Gogh / WikiArt

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February 17, 2023