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Michael: So you’re out on date, and really jonesing for some Italian food.

You head to the restaurant, have a nice dinner, and it’s not until after the fact that you realize your breath -- and your entire being -- reeks. Oh, garlic... so delicious... and yet so treacherous.

Why do you do this to us? Well, garlic breath, like most things, has to do with chemistry. You may have noticed that whole, unpeeled garlic doesn’t smell very much. That’s because the chemical compounds responsible for that classic garlicky aroma only form if the bulb is physically damaged.

When you chop, crush, or otherwise mangle a clove for your favorite recipe, you end up releasing alliinase [a-lee-in-ase] enzymes, which quickly get to work breaking down odorless alliin [a-lee-in] compounds in the garlic into allicin [a-liss-in] -- the stinky stuff. So it’s the allicin you’re smelling on your hands and the cutting boarding, but it soon breaks down into a bunch of other compounds, a lot of which contain sulfur. And those compounds are where your garlic breath comes from.

Take a bite, and it’s these guys that hang around in your mouth, stinking up the place. One compound -- allyl [a-lill] methyl sulfide, or AMS -- really tends to outstay its welcome. It’s the one that takes the longest to break down, and it can linger for a whole day or two.

Now, brushing your teeth and physically scrubbing these molecules off your tongue may help lessen your death breath a little, but part of what makes garlic breath so notorious is its persistence. Once it’s ingested and absorbed by your intestines, that stinky AMS enters your bloodstream intact, and eventually makes it way to the organs that will ultimately excrete it -- your kidneys, lungs, and skin. Which is how that distinct garlic smell can resurface again in your pee, breath, and sweat, and continue to haunt you long after your last bite of lasagna.

Okay, so you love your garlic, but you also enjoy talking to and/or or kissing people without making them recoil. Is there anything you can do to get rid of the smell? Well, some research has found that eating certain foods, like parsley, apples, spinach, mushrooms, basil, and citrus may help make garlic breath at least a little bit less intense. We’re not exactly sure how they work, but researchers think these foods may contain certain enzymes or other molecules that help deodorize or break down those smelly sulfur compounds.

And a 2010 study published in The Journal of Food Science suggests that the high fat and water content in milk may also help deodorize AMS molecules more quickly, especially if you drink it while you’re eating your garlic. Still, I wouldn’t count on any of that stuff to bail you out before an important meeting or romantic evening... and a lot of food chemists just recommend trying to mask the smell with a different odor, like a breath mint. Or twelve.

And uh, try not to sweat too much. Thanks for asking, and thanks especially to our President of Space, Morgan, who is biking across the United States from west to east raising money for the YouTube content he loves, like us here at SciShow and Crash Course. You can follow his journey at thebigtryhard.com.