Just curious how long it takes for carbohydrates to be broken down to glucose etc. and proteins to be used for all the types of synthesis they're used for once they're ingested? I was thinking about those sports drinks which have alot of sugar. In the past it made sense that drinking something sweet during physical activity would supply sugar for respiration, but doesn't it take something like 15 hours for digested food to reach the large intestine where absorbtion of nutrients takes place? Are there other places in the digestive system where things can be absorbed, or do liquids travel through the digestive system faster?