think of your metabolism as your engine. IF you're trying to get top speed out of a car filled with water, your engine will soon be destroyed. So basically if you eat transfats which are plastic to your arteries ( mono and diglycerides and also hydrogenated and partially hydrogenated fats)and you consume acidic sodas which suck life out of your bones and organs and you dont eat fiber to stay regular and your idea of veggies is cooked with butter, you should expect a sluggish metabolism. And if you are eating healthy but still no luck, try 1 week water fast and or afterwards doing colonics and enemas and then a jucie fast. Most likely you may alergic to something and the toxic buildup is eating all the vitamins in your intestines therby not allowing you to reap the benefits