Bernadette,Thanks for the question and comment. You probably already know this stuff but I will post it for others that may not. I will say for people that have digestive issues limiting or avoiding certain foods is necessary.
I have been reading these claims for years and have yet to find real science behind these claims. I regularly mix all types of foods together. My major rule is many more veggies than fruits because of the sugar content of fruits. The problem I find is when man tries to outthink the body. You can't, because if provided adequate nutrition the body detoxifies and self corrects for optimal health.
Our digestive system is highly complex and next to our skin our largest organ. It runs as a single membrane (the lumen) from our mouth to our anus. During digestion the body is balancing pH, releasing enzymes and other compounds to make nutrient absorption happen. The body releases different enzymes from the pancreas and other GI organs as the intestines signal a need for specific chemicals and enzymes.
Lets look at basic digestive biology to answer the question.
1) There are three major classes of enzymes, amylases, proteases and lipases. These digest carbohydrates, proteins and fats. Almost every food contains all three of these macronutrient classes. So enzymes are mixed in nature.
2) All raw plants provide their own digestive enzymes and other enzymes to take car of major digestion. Thats the beauty of eating raw plant foods!
3) All digestion begins with chewing. The stomach dissolves all foods into manageable particle size for the intestines to digest.
4)The stomach begins the digestive process for proteins where as carbohydrate digestion begins in the mouth, stops in the stomach and finishes in the intestines.
5) Fats are chewed and melted in the mouth but digested in the intestines.
Every second of our lives our body is adjusting it's response to our dietary and physical exposure and the demands we ask of it. As long as we live a healthy lifestyle and eat living foods with living enzymes our body is going to respond by giving each of us our optimal health potential.
Healthy Wishes, Wally Bishop C.N.C.