When I first became aware that there was more to health in foods than low fat, no fat, low calories, low cholesterol, and some fruits and vegetables...when I came to the realization that the foods I was eating were filled with chemicals and poisons I abruptly stopped eating my normal diet and ate mainly fruits and vegetables. Now the result of this was terrible. Yes, terrible.
Being extremely uneducated in what a good diet actually is, I simply removed what I knew wasn't and my body did not handle this change well. I became sick with fever, stomach pains, and vomiting. I felt terrible. Now you'd think that changing to a healthy diet would produce fabulous results, and it truly does, but being a complete novice I put a great stress on my body by not transitioning my diet change and by not providing myself with all the nutrients, vitamins, fats, and so on, that the human body needs.
I soon realized that my diet of lots of apples, broccoli, and whatever else I could find was causing the issue. I returned to my old SAD (Standard American Diet) and the terrible pains and sickness went away.
Now I completely believe that one part of being truly healthy is eating a largely raw and organic diet. However, if you decide that you'd like to make the change I highly recommend easing your body and mind into the transition.
Instead of causing a lot of shock and stress on my body, when I finally decided to change my diet for good I eased into the transition. I slowly transitioned to primarily organic foods and added more fruits and vegetables into my diet. Next I removed the canned and boxed organic foods from my diet and began mainly eating organic items from the produce isle in your typical grocery or health food store. I slowly weaned myself off dairy and lots of meats, although I still do eat some meat. I also eased into nutritional supplements like whole food supplements, super foods, and other similar items, instead of suddenly taking all at once beginning one day.
This transition to a healthy diet had no obvious symptoms that I could detect, besides feeling more full of energy and healthy. I also felt happier.
So, if you want to change your diet, don't do it over night, but also don't make excuses to eat junk still. You will know when it's time to stop eating chips and candy bars and don't let yourself use the transition process as a crutch to still eat junk.
Probably most importantly is that transitioning your diet will help you over many mental hurdles you will encounter. It is a lot easier to eat the right foods and food combinations when you are eating primarily organic whole foods already, than if you are used to eating pizza for breakfast and McDonalds for lunch.
Finally, when you do hit a mental hurdle and fail to overcome it and fall to the temptation of unhealthy foods realize that it is part of the process and push on. You must look at your poor food choice as a learning lesson and remove any guilt you may have over it and put it behind you. Push on and move forward.