Our digestive system is a wonderful and complex thing, but it's not so complex that you need to carefully calibrate your meals to avoid food rotting in your stomach. That's the bogus theory of "food combining", and here's why it's nonsense.
Image from Thomas Fisher Rare Book Library
In the theory of food combining, our digestive tract goes haywire if we feed it the wrong thing at the wrong time. If you eat acidic fruit with a protein-rich meal, for instance, proponents say that you won't be able to digest the protein and it will rot in your stomach.
Dietician Tamara Duker Freuman debunks these myths at US News. "There is only one circumstance under which you'd need to worry about food rotting in your stomach, and that is if you were to die mid-meal," she writes. Acid foods don't cause problems because your stomach's cells control acid levels, making more or less as needed.
Freuman puts other food-combining myths to rest while she's at it, including the idea that you have to eat certain foods on their own for proper digestion. "Just as you can walk and chew gum at the same time, so can your gut can absorb meat and grains — or frankly, any combination of food — at the same time as well. Don't underestimate it!"
Debunking the Myth of Food Combining [US News]