Hint: It has to do with the caffeine.
核心提示：燃烧脂肪的功能来自咖啡 因（ caffeine，下面X为’因‘字）
Experts talk about how important hydration is for health and weight loss. And they also talk a lot about how to cut down on calories in things like your daily coffee. Now, new research shows that one cup of plain coffee could stimulate “brown fat”—and it might be another breakthrough for weight loss research.
What is brown fat?