Most people know that regular exercise is a key part of living a healthy life. But the benefits of physical activity go beyond keeping your waistline trim and building a stronger cardiovascular system. Moving your body isn’t just good for your heart and for building stronger bones and muscles, a new study shows it’s beneficial for another major organ, your liver.
The Tsunami of Non-Alcoholic Liver Disease (NAFLD)
Non-alcoholic fatty liver disease (NAFLD) is the most common liver disease in the world. It occurs when fat builds up around the liver, which can, over time, cause inflammation and damage to the organ. Although this condition can occur in people of any age and gender, it’s more common in overweight or obese people. It’s also a risk factor for other types of liver conditions such as alcoholic hepatitis, fibrosis, and cirrhosis.
The problem with NAFLD is there isn’t an effective treatment for it. Since it occurs more often in people who are overweight or obese, weight loss can help and even reverse non-alcoholic fatty liver disease. Around 9 out of 10 people who are obese have NAFLD while 3 out of 4 overweight people have some excess fat build-up around their liver.
Can exercise help? A new study finds that obese Japanese men who took part in an aerobic exercise program for 90 minutes 3 times weekly experienced improved markers of liver health as well as a reduction in inflammatory markers and markers of oxidative stress, all beneficial for liver health. Plus, these changes occurred even when the participants lost no weight.
Therefore, exercise may benefit people with NAFLD even if it doesn’t lead to significant weight loss. How might exercise benefit a fatty liver and improve liver health?
Exercise Improves Insulin Sensitivity
Insulin resistance is a condition in which the body doesn’t use insulin efficiently. Insulin helps your body process glucose (sugar), and if you have insulin resistance, your body can’t use it as efficiently to get glucose into cells. Insulin resistance, over time, can lead to type 2 diabetes, which causes high blood glucose levels and damage to organs and blood vessels. Type 2 diabetes is a multi-system disease and one that can shorten lifespan.
Exercise improves insulin sensitivity by encouraging cells to take up glucose even without insulin. In response to exercise, cells are better able to accept glucose without requiring more insulin release, and less stays in your bloodstream. Studies show a single bout of exercise enhances insulin sensitivity, how cells take up glucose for up to 16 hours afterward.
Insulin resistance and NAFLD are closely intertwined. People with NAFLD have significant impairments in insulin sensitivity and that drives the progression of fat build-up in the liver. Insulin resistance drives the inflammation that develops in some people with NAFLD, which worsens the condition and increases the risk of cirrhosis or liver scarring.
Therefore, anything that improves insulin sensitivity, including exercise and weight loss, has a beneficial effect on non-alcoholic fatty liver disease. Exercise also helps prevent heart disease by improving cholesterol levels and lowering triglyceride concentrations in the bloodstream; these two improvements reduce the risk of coronary artery disease (CAD).
Weight Loss for Liver Health
Exercise can help you lose weight and the more weight you lose the more insulin sensitivity improves. Although losing weight alone benefits insulin function and non-alcoholic fatty liver, the combination has synergy. Even losing 5 to 10% of your body weight is enough to improve markers of liver health, blood glucose control, and improve insulin sensitivity.
The human liver is the largest internal organ in the body, weighing about 3 pounds. It is located in the upper right quadrant of your abdomen and receives blood from a network of veins, arteries, and ducts that form the hepatic portal system. One of its key functions is to detoxify. When you take a medication, your liver is what breaks it down.
Your liver also stores some vitamins, like vitamin B12, and stores excess sugar as glycogen. Plus, it synthesizes key proteins, like those that maintain fluid balance in your blood vessels, and breaks down proteins from the food you eat into smaller molecules that are used to build new proteins. You might wonder whether exercise improves your liver’s ability to perform these functions.
Exercise boosts energy levels by increasing blood flow throughout your body, which brings more oxygen to cells—including those inside your liver to optimize liver function. This increased circulation means better nutrient intake for those organs as well as faster waste removal from them for greater efficiency. Studies show that exercise improves markers of liver function.
Overall, exercise can be a great way to improve your liver health. It’s not just aerobic exercise that has benefits. Some research shows resistance training also reduces the build-up of fat in the liver. Exercise intensity doesn’t appear to be a factor either. Studies show varying volumes and intensities of exercise are beneficial for reducing liver fat and visceral fat that’s harmful to other organs. These changes occur even in the absence of weight loss.
Whether you’re looking to get fitter, lose weight or alleviate the symptoms of non-alcoholic fatty liver disease, exercise can help you achieve these goals. However, it’s important to consult a doctor before starting any exercise routine to ensure that you’re doing what’s best for your health. However, smart doctors are prescribing exercise for many health conditions!
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