Green tea extract may help the body use fat more efficiently during physical activity, according to a new review of clinical trials. Researchers found that the supplement increased fat oxidation, or the rate at which the body burns fat for energy, during and after exercise. The study, published in Nutrition Reviews, pooled data from nine randomized controlled trials to examine how green tea extract affects fuel utilization.
What the study found
The analysis focused on substrate oxidation, a measure of which fuel the body relies on. Participants who took green tea extract burned more fat during their workout and continued to burn fat afterward. Carbohydrate oxidation decreased during recovery, suggesting the body relied less on carbs and more on fat afterward. Higher doses of the extract were linked to even greater increases in post-exercise fat oxidation.
The findings indicate that green tea extract helps support metabolic flexibility. This term describes the body’s ability to switch between using carbohydrates and fat for energy. A metabolically flexible system can easily change fuel sources depending on the activity level and food intake. Poor flexibility is often linked to insulin resistance and poor blood sugar control. The new study suggests green tea extract may act as a tool to improve this ability, especially when combined with exercise.
Research Details and Fat Loss Context
The analysis examined rates of fat and carbohydrate oxidation during exercise and recovery. Researchers reviewed data from nine randomized controlled trials to assess the supplement’s effects. They also conducted a dose-response analysis to see if larger amounts produced different results.
Context and limitations
The research did not specifically measure weight loss. Improving metabolic flexibility does not guarantee fat loss without a calorie deficit or other dietary changes. However, previous studies on green tea extract have shown benefits for weight management when combined with lifestyle adjustments. The supplement is commonly found in products marketed for metabolism support.