Brushing your teeth after a garlicky meal helps.
Then, annoyingly, the garlic smell can come back.
That happens because not all garlic breath is sitting inside your mouth.
Part of it can come from inside the body.
Crushing garlic creates strong-smelling chemicals
When garlic is chopped, chewed, or crushed, chemical reactions create several sulfur-containing compounds.
Some stay in the mouth and can be reduced by brushing, flossing, rinsing, and cleaning the tongue.
That is the easy part.
Some compounds are absorbed during digestion
Certain garlic compounds or their breakdown products can pass from the digestive system into the bloodstream.
One especially persistent compound can circulate through the body and eventually reach the lungs.
Now the smell has a new route out.
You breathe some of it back out
As blood passes through the lungs, volatile compounds can move into the air you exhale.
That means the odor is no longer simply trapped between your teeth.
You are literally breathing some of it out from inside the body.
This is different from ordinary morning breath, where reduced saliva and bacterial activity in the mouth play a major role.
Why does brushing not completely fix it?
Toothpaste can remove food particles and reduce odors in the mouth.
It cannot instantly remove compounds already circulating in your bloodstream.
You have to wait while the body breaks them down and eliminates them.
Do foods like parsley or milk help?
Some foods may reduce certain garlic odors in the mouth or interact with odor-producing compounds.
They may help.
But nothing you chew can immediately pull every circulating sulfur compound out of the bloodstream.
Why is garlic smell so strong?
Human noses are very sensitive to some sulfur compounds.
A relatively small amount can produce a very noticeable odor.
That is why the effect can survive several rounds of gum, mints, and optimistic toothbrushing.
So after a garlicky meal, toothpaste can only do part of the job.
Sometimes the smell is no longer in your mouth.
It is making the return trip through your lungs.
And that’s the short explanation.
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