Damn Garlic!

So I am reading Do Polar Bears get lonely? It's full of interesting science questions and answers. I thought I'd share one of them.

Q. Why does Garlic make your breath smell in a way that, say, lettuce and potatoes do not?

A. Garlic produces a potent antifungal and antibacterial compound called allicin when the clove is cut or crushed. This is created by the enzyme alliinase acting on a compound called aliin. Allicin is responsible for the burning sensation you experience if you eat garlic raw.
However, allicin is not stable and generates numerous smelly sulphur-containing compounds, hence its pungent smell. After ingestion, allicin and its breakdown products enter the bloodstream through the digestive system and are free to leave again in exhaled air or through perspiration. This is the first effect of garlic.
In addition, the chemicals in garlic change the metabolism of the body and trigger degradation of fatty acids and cholesteral in the blood: this generates allyl methyl sulphide, dimethyl sulphide and acetone. These are all volatile and can be exhaled from the lungs, giving you garlic breath the morning after a meal. It is not necessary to eat garlic to have garlic breath because allicin can be absorbed through the skin. Just rubbing garlic on the surface of the body can be enough to generate smelly breath because it exits the body via the lungs.