Reintroducing Food Into Your Diet After a Clean Challenge
If you would like to find some level of compromise between eating 100% clean and the good old days of PB&Js, Captain Crunch, Doritos and Haagen-Dazs, we strongly encourage you to use a structured food reintroduction process to highlight your food sensitivities.
After eliminating foods for 2-4 weeks
To do this, add a single major food type, like dairy, every 3 days to give your body time to react. Make sure to consume a solid quantity (yes, here is your license to pig out!) so that your sensitivities are noticeable. So if you're adding back dairy, do it at breakfast, lunch and dinner and note what happens. Sometimes you can handle a small amount but then there's a tipping point. When you add in foods, pay attention to how your clothes fit, how your stomach feels, etc...any bloating or stomach cramps? How's your skin? Any headaches?
If you have no major issues, you have license to add this food back into your diet. Wait at least 3 days and then proceed to the next food down the list. However, if it caused problems, you can try adding it back later or you may wish to consider permanently eliminating it from your diet. It's important to take it out of your diet for at least 3 days before you try to reintroduce another food, because you want to get back to feeling really good or you won't get a clear picture of what could be causing the problem. If you try adding it back again and you get the same issues, ask yourself the question, "is it worth it?". Some things are definitely worth it for all of us, and some just are not. Once you've made your decision, move to the next food down the list.
The following foods are the most likely to cause problems for people - listed from most offensive to least offensive (problems being digestive problems, skin issues, migraines, and energy issues for people in that order).
Gluten
Grains
Dairy
Beans (including soy)
Sugar
Nuts and Seeds
This topic is also covered extensively in Chris Kresser's Your Personal Paleo Code.