Your liver is designed to absorb dietary fats and turn them into cholesterol, which is then used for the production of hormones, cellular walls, and more. Your liver also produces glucose for energy. It’s to be expected that the liver will store a certain amount of fat (and calories) to have available in case of low food consumption or high energy expenditure. But if more than 5-10% of the weight of your liver is fat, it means you may have fatty liver disease.
A lot of cases of fatty liver disease are caused by alcohol intake, but non-alcoholic fatty liver disease (NAFLD) is just as common. The problem is, doctors, don’t know exactly what causes NAFLD. They know it’s genetic and more common among the middle-aged, obese, and overweight, those with high cholesterol and diabetes, and the malnourished. However, there have been no specific causes of the problem pinpointed.
Thankfully, there are things you can do to protect your liver against excess fat build-up. Better still, you can reverse a build-up of fat and fight fatty liver disease. How? Simple: exercise.
Finnish researchers from the University of Turku discovered that cardiorespiratory fitness was inversely correlated to fatty liver disease risk. To put that in simple terms: the fitter you are, the lower the chance you’ll suffer from a non-alcoholic fatty liver disease.
Over 460 Finnish adults between the ages of 30 and 47 participated in the study. The researchers measured their liver fat content using an ultrasound, and all the participants were subjected to a cardiorespiratory fitness test (using a cycle ergometer).
The researchers found that cardiorespiratory fitness was the single most important factor in the risk of fatty liver disease. Obesity wasn’t as important, nor was alcohol use, smoking, physical activity, C-reactive proteins, glucose, insulin, or lipid levels. Even the overweight and obese participants with decent cardiorespiratory fitness had a lower risk of fatty liver disease than the normal weight participants with poor cardiorespiratory fitness.
“The study revealed that cardiorespiratory fitness is inversely related to the risk of fatty liver — despite physical activity, smoking, alcohol use, serum lipids, insulin, glucose, and C-reactive protein. Importantly, the same results could be seen in participants who were obese,” says Researcher Kristiina Pälve from Research Centre of Applied and Preventive Cardiovascular Medicine of the University of Turku.
The research results are significant for public health: despite the person’s weight, achieving a moderate level of cardiorespiratory fitness can protect from fatty liver. Fatty liver is a significant and expanding public health concern. It is related to several metabolic disturbances, increased risk of cardiovascular disease and type 2 diabetes.
1. Pälve KS, Pahkala K, Suomela E, Aatola H, Hulkkonen J, Juonala M, Lehtimäki T, Rönnemaa T, Viikari JS, Kähönen M, Hutri-Kähönen N, Telama R, Tammelin T, Raitakari OT. “Cardiorespiratory Fitness and Risk of Fatty Liver. The Young Finns Study.” Medicine & Science in Sports & Exercise, May 2017.