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Why does garlic give you bad breath? © Getty Images

Why does garlic give you bad breath?

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If you want to know how to get rid of garlic breath we've got some bad news for you.

Asked by: Alison Smith, London

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Garlic contains a chemical called allyl cysteine sulphoxide or ‘alliin’. When a raw garlic clove is crushed or chopped, an enzyme in the garlic cells is released that reacts in a matter of seconds with the alliin to produce a chemical called allicin. This breaks down into lots of other chemicals, most of them stinky.

Nearly all of these chemicals are broken down in your stomach and liver, but allyl methyl sulphide is one that survives to be absorbed into the bloodstream intact. This means that it can diffuse out through your lungs into the air you exhale for up to two days. Brushing your teeth has only limited effect because the chemical is still in your blood.


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Authors

luis villazon
Luis VillazonQ&A expert

Luis trained as a zoologist, but now works as a science and technology educator. In his spare time he builds 3D-printed robots, in the hope that he will be spared when the revolution inevitably comes.

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