Clean eating is all about reducing the footprint of man-made substances in your diet. The reasons you would want to do this are many, but the most important one, from a purely selfish point of view, is that you want to improve your own health by doing so. Clean eating is one of the main topics covered in Carolyn Hansen's book "21 Days To Healthy Eating":
You may be wondering whether there is a difference between eating clean and eating organic. Well, eating organic foods is a subset of eating clean foods. You will not always be in the position to choose between eating an organically-grown piece of fruit (free of all pesticides) and one that may have come in contact with chemical substances during the period in which it was grown. Organic foods are always to be preferred, but a properly treated (washed and possibly peeled) fruit or vegetable that has been exposed to chemicals is going to be a lot more nutritious eaten raw or lightly cooked than the same food after it has gone through a processing line.
As an example, take a jar of peaches floating in syrup. Those are probably not organically grown peaches in that jar. But they are peeled, and you would be a lot better off eating the peeled fruit just after it has been taken from the tree, than to eat those processed and jarred peaches. That sugary syrup they float in is full of preservatives and is obviously high in sugar content - perfect for adding a large number of calories to your meal. You know what happens when you eat an excess of sugar, right? It is converted into fat.
Actually sugar does a lot more harm in the long run than to simply make you fat. But the point we are trying to make here is that it is the "processed" nature of foods that we are trying to avoid when eating clean. We are also trying to avoid added chemicals in whatever form they might come in. So there are "degrees" of cleanliness when it comes to choosing our clean foods. Pure organically grown foods that are never processed for distribution, or packaged, before they are eaten, are probably the cleanest foods.
You can find the clean foods on the inside walls of your supermarket. This is where you find produce and meats that have a limited shelf life. Whenever you can manage it, avoid using the inner aisles of the store. This is where you will find aisle after aisle of processed foods that have a very long shelf life because they have had the "living components" extinguished before being packaged. Usually this means all the valuable enzymatic components of the food have been destroyed, components that carry much of the nutrition that could have benefited your body, but now have been removed.
A little appreciated fact about processed foods is that the chemicals they carry slowly poison your body, and that in response to this the body tries to seal off the "pollutants" by wrapping them in protective fat. The body tries to insulate the critical organs from the effects of these chemicals. The end result, though, is pounds and pounds of extra fat over time. Not only that, but the more of this "polluted fat" you carry, the harder it is to shed it because to do so would involve flooding your body with the toxins that have been stored away for protection.
So before you can lose a lot of your fat reserves, particularly if you make a habit of eating processed foods, you will need to detoxify your body by eating clean for a length of time. To learn more about how this all works, and what kind of meals you can prepare that stick closely to this clean eating concept, check out "21 Days To Healthy Eating":
You will find lots of practical advice on how to shop for clean foods, how to prepare clean meals that have the right balance of food groups to ensure optimal fat-burning, and further tips to ensure that you can get rid of the excess fat on your body that might have built up from years of eating processed foods.