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Can you please tell me the digestive timeline for protein, fat, and starch?
Question Date: 2009-11-26
Answer 1:

For healthy adults, digestion of food usually takes between 24 and 72 hours. After you eat, it takes about six to eight hours for food to pass through your stomach and small intestine. Food then enters your large intestine (colon) for further digestion and absorption of water. Elimination of undigested food residue through the large intestine usually begins after 24 hours. Complete elimination from the body may take several days.

As far as you question regarding the digestive timeline for protein, fat, and starch I was not able to find very good estimates. This is due to the fact that the digestion rates can very based on the components of a given meal. Generally speaking, carbohydrates tend to spend the least amount of time in the stomach, while protein stays in the stomach longer, and fats the longest. The time it takes to metabolize carbohydrates depends on the type. Simple sugars are metabolized much faster than more complex carbohydrates. For your reference you can view the following website.

Digesting Time for Some Common Foods Green Vegetables (non-starch) - 5 hours Raw Juices-15 minutes

Fat-12 hours Protein (meat)-12 hours

Protein (starch)-12 hours Protein (fat)-12 hours

Starch-5 hours Mild Starch-5 hours

Fruit, Sweet/Dried-3 hours Fruit (Acid)-2 hours

Fruit (Sub-Acid)-2 hours Fruit, Sweet/Fresh-3 hours

Melon-2 hours Syrup, Sugar-2 hours

Milk-12 hours

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