Theoretically, if I were to eat a piece of fruit or something else that is mostly carbs, would it be better to eat it by itself - i.e. without any protein or fat in the meal? My thinking is that an insulin response allows the body to store fat, so limiting the number of calories consumed while insulin levels are high would limit the amount of energy that is stored as fat. I've also heard - mostly from CW - that mixing your carbs with fat, protein and fiber decreases severity of the associated blood sugar spike. However, it seems like that would not be what you want - at least not for fat loss. A certain amount of insulin would need to be released to counter the amount of carbohydrate consumed and spreading it over a longer period of time as well as ingesting more calories that could be stored as fat seems like it would encourage more energy to be stored as fat.
This isn't really for practical use, just curious about the mechanics of it.
Cordain addressed this topic in an article.
He hinted that there may be something to it.
Some people, like the Gracies', follow a food
combining diet. They only combine certain food
groups. The wrong combination can turn otherwise
good foods into a toxic mess. At least according
to their folklore. I am looking forward to getting
their diet book when it is released. I am hoping
they will address some of the chemistry of food
combinations beyond macronutrients percentages.
While eating a more dense carbohydrate with protein, or fat will blunt the insulin response, by delaying gastric emptying. This can also be accomplished with lime juice, or vinegar I believe. The acid also serve to delay the gastric emptying. In practical terms for fat loss I would worry less about what I combined with fruit or more dense carbs, and focus instead on both the frequency of their intake and if possible pair these foods with glycogen depleting activities (ie post workout). For most effective weight-loss and dealing with those who are severely insulin resistance the complete elimination of fruits from the diet is a common recommendation.
For me, I find that as long as I keep my carb calories under a certain percent of my total calories, I do fine. But if I were to eat fruit alone the resulting spike and drop would send me craving more carbs!!
I never eat fruit alone. With a meal or snack, always with protein and fat....mainly fat.