New research is revealing that consuming grapefruit benefits weight loss in a a major way. The key may be an enzyme called AMP activated protein kinase (AMPK) that is found in Grapefruit. AMPK s helps your body utilize sugar which results in boosting your metabolism resulting in. Nootkatone a component found in grapefruit has been shown to significantly increase fat burning (AMPK) activity. Consider grapefruit as vitamin C rich snack, add grapefruit slices to a spinach salad, or even into an immune boosting smoothie.