Garlic lovers will surely appreciate this new study, and so will their friends and family: Raw apples, mint, and lettuce contain chemicals that can destroy the volatile compounds that cause smelly breath after eating the pungent spice, according to a new study from Ohio State University. The researchers hope their findings may lead to a new pill for garlic-induced halitosis, but for now they say that enjoying some post-meal fruit or veggies can make a big difference, too.
“It’s one of those flavors we really like to have in our food, but the downside is that the garlic will linger on your breath for up to 24 hours—which isn’t so pleasant,” said co-author Sheryl Barringer, Ph.D., professor of food science and technology, in a video interview with the Journal of Food Science, where the study is published. “So we’ve been looking at how you can use foods to deodorize your breath.”
From their previous studies, the researchers knew that some foods worked better than others to neutralize garlic breath, and they theorized that two separate factors are responsible: Phenolic compounds, which are antioxidants found in fruits and vegetables; and enzymes, which are proteins that help speed up chemical reactions.
Chewing a clove of garlic (or eating foods made with sliced or crushed cloves) releases a compound called allicin, which breaks down into volatile chemicals that are released into the stomach and bloodstream, and then out of the body through the breath.
“When you consume foods that have phenolic compounds, these phenolics react with those volatiles and they destroy them,” Barringer explained. “The enzymes speed up the reaction, so if you have a raw fruit or vegetable that has these enzymes, then this reaction happens faster and this deodorization occurs more rapidly.”
To test their theory—and see which specific phenolic compounds and enzymes worked best—the researchers asked volunteers to chew 3 grams of softneck garlic cloves for 25 seconds. The volunteers then ate or drank either Fuji apples (raw, juiced, or heated), iceberg lettuce (raw or heated), spearmint leaves (raw, juiced, or heated), green tea, or water.
Throughout the next hour, the volunteers were asked to blow into a device called a spectrometer, which measured the levels of common garlic-breath compounds, such as diallyl disulfide and allyl methyl sulfide.
Those results showed that that raw apple, raw lettuce, and raw mint leaves decreased the concentration of these volatile compounds by 50 percent or more, compared to the group that drank only water. All three foods provided a significant deodorizing effect, but mint leaves—which have the highest phenolic content—came out slightly ahead of the others.
Apple juice and mint juice, which had been strained to remove the phenolic compounds, didn’t work nearly as well as their whole-food versions did—supporting the researchers’ theory that these compounds do indeed play a large role. The heated apple and lettuce also provided a significant reduction in volatiles, but again, not as much as the raw ones. (Heating produce can destroy the enzymes that seem to help make the phenolic reactions so effective, said Barringer.)
Green tea, which contains a different type of phenolic compound, had no deodorizing effect.
This study only looked at the phenolic compounds and enzymes in four specific foods, but Barringer notes that there are many others that have potential as odor neutralizers, too. Her team plans to continue studying different ingredients, in hopes of finding the most effective compounds that may one day be used in a pill to treat garlic breath.
You don’t have to wait until that happens to put these study findings to good use, however. “If you’re worried about garlic breath, my short answer would be eat apples, eat raw mint,” she said. “Both were very effective ways to deodorize garlic breath.” Given all the healthy reasons to eat more garlic, this seems like one experiment that’s certainly worth a try.