Question

Why is alcohol is absorbed by the body much faster than food?

Answer 1

Because alcohol i.e mostly ethanol `(C_2H_5OH)` no needs to be digested as normal food stuff which contains complex molecules like carbohydrates, proteins, lipids etc...

Explanation:

Due to liquidy nature of alcohol, it enters the stomach immediately after entering the buccal cavity.

Once it reaches stomach, `20%` of alcohol is instantly absorbed in stomach-- specially when there is no food present in the stomach. After that, it would immediately move into small intestine where it would find an immense surface area for it's absorption. From small intestine `80%` of alcohol is rapidly absorbed into blood.
Because of their small size and polar nature, ethanol molecules find no difficulty in crossing the plasma membranes of endothelial cells. They passively diffuse into the endothelial cells lining stomach as well as small intestine.

That's why, the BAC(blood alcohol concentration) increases immediately after consumption of alcohol. Alcohol appears in blood stream within 15 minutes of consumption of alcohol.

But there is also an exception. If the stomach is already filled with food stuff then pyloric sphincter, present at the junction of the stomach and small intestine, remains closed. Hence it prevents alcohol to immediately enter the small intestine. Thus the rate of alcohol absorption does not suddenly increase. Fatty foods particularly decrease it's absorption as such foods stay in stomach for longer period.

Hope it helps...