Gamma-glutamyl transferase (GGT) is an enzyme found predominantly in the liver, where it helps cells manage stress and process toxins. When liver cells or the bile ducts are damaged, GGT leaks into the bloodstream, resulting in elevated levels detected in a blood test. A high GGT reading indicates stress on the liver, suggesting the organ is overworked by toxins, inflammation, or fat accumulation. While a medical professional must diagnose the underlying cause, adjusting your diet can significantly reduce this burden by eliminating substances that place direct metabolic or toxic stress on the liver.
Alcoholic Beverages
Consumption of alcoholic beverages is the most common cause of a high GGT level. The liver breaks down ethanol into acetaldehyde, a highly reactive and toxic compound that leads to oxidative stress within the hepatocytes. This stress directly stimulates the production and release of the GGT enzyme as the liver attempts to protect itself and replenish its primary antioxidant, glutathione.
Even moderate consumption can cause GGT levels to rise because the enzyme is highly sensitive to alcohol. When GGT is elevated, physicians typically recommend immediate and complete abstinence from all alcohol-containing products. Total avoidance is often necessary until GGT levels normalize, a process that can take several weeks or months. Continuing to drink prevents recovery and risks the progression to more serious liver disease.
Refined Sugars and High-Fructose Corn Syrup
Refined sugars, especially those containing fructose, are strongly linked to Non-Alcoholic Fatty Liver Disease (NAFLD), a major driver of elevated GGT in non-drinkers. Fructose is metabolized almost exclusively by the liver, unlike glucose, which can be used by nearly all body tissues. When the liver receives excessive fructose, it rapidly converts it into fat through a process called de novo lipogenesis.
This conversion process is highly unregulated, leading to fat buildup and inflammation in liver tissue, which releases GGT into the blood. Fructose metabolism also produces uric acid, which further contributes to cellular stress and inflammation. Foods to eliminate include sugary sodas, fruit juices with added sugar, packaged baked goods, candies, and many breakfast cereals that rely on these concentrated sweeteners. Reducing the liver’s fat load by cutting these sugars is a primary dietary intervention for lowering GGT.
Sources of Unhealthy Dietary Fats
Certain dietary fats promote inflammation and oxidative stress in the liver, which keeps GGT levels elevated. Specifically, trans fats, found in commercially fried foods and highly processed snacks, should be strictly avoided. These manufactured fats are difficult for the body to process and directly increase systemic inflammation.
Excessive saturated fats, commonly found in high-fat red meats, lard, and full-fat dairy products, also contribute to fat accumulation seen in NAFLD. Highly refined vegetable oils rich in Omega-6 fatty acids are frequently used in commercial frying and cooking. When heated, these oils can become oxidized, creating pro-inflammatory compounds that damage liver cells and increase oxidative stress. Choosing lean proteins and prioritizing healthy, unheated fats like olive oil or avocado oil reduces the inflammatory pressure on the liver.