How Coffee Can Help Reduce Bad Breath, According to Israeli Study

If you’ve ever popped a piece of gum to mask morning breath or post-lunch onion breath, you’re not alone—but that minty fix doesn’t last, and it might even irritate your stomach over time. What if the answer to fresher breath was already in your mug?

Yes, coffee. A 2012 study by Israeli scientists found that coffee can reduce bad breath by up to 90% in lab tests, blocking the production of foul-smelling sulfur gases rather than causing them.

The Coffee and Bad Breath Misconception

It’s a common belief that coffee makes your breath worse—especially when mixed with milk, which can dry out your mouth and promote bacterial fermentation. But that’s not the whole story. Researchers at Tel Aviv University, led by Professor Mel Rosenberg, an expert in halitosis (the technical term for bad breath), set out to prove coffee worsens breath—but ended up discovering the opposite.

What Actually Causes Bad Breath?

Bad breath starts in places like your tongue and gumline, where bacteria form plaque and release volatile sulfur compounds (VSCs)—the real culprits behind that unpleasant odor. Eating strong foods like garlic or onions makes it worse because their compounds enter your bloodstream, travel to your lungs, and come out when you exhale. Even healthy people wake up with morning breath due to reduced saliva flow overnight.

The Surprising Coffee Experiment

In their experiment, Rosenberg’s team placed samples of two locally produced Israeli coffees and one Nestlé instant coffee into test tubes containing saliva. Their initial hypothesis? That coffee would increase the production of bad-smelling gases. Instead, they observed the opposite: coffee inhibited the formation of these gases. In some trials, it reduced VSC production by as much as 90%. “We expected coffee to cause bad breath,” Rosenberg said. “But we found it actually contains components that suppress it.”

Future Applications: Beyond the Mug

Rosenberg believes the active compounds in coffee that fight bad breath could be isolated and used in products like mouthwash, chewing gum, or breath sprays—offering a longer-lasting solution than current options that just mask odors. He aims to develop agents that prevent plaque buildup and stop bad breath at the source, potentially replacing traditional breath fresheners that only provide temporary relief.

Frequently Asked Questions

Does coffee really reduce bad breath?

Yes. A 2012 study by Israeli researchers found that coffee can reduce the production of volatile sulfur compounds—the main cause of bad breath—by up to 90% in laboratory tests using saliva samples.

What causes bad breath in the first place?

Bad breath is primarily caused by volatile sulfur compounds (VSCs) released by bacteria in the mouth, especially on the tongue and gums. Foods like garlic and onions can worsen it as their compounds enter the bloodstream and are exhaled through the lungs.

Why do people think coffee makes breath worse?

Coffee is often believed to cause bad breath, especially when mixed with milk, which can dry the mouth and promote bacterial activity. However, the study showed that coffee itself contains compounds that inhibit, rather than increase, bad breath.

Can coffee replace gum or mouthwash for fresh breath?

Potentially. The active substances in coffee that suppress bad breath might be extracted for use in future mouthwashes, chewing gums, or sprays, offering a longer-lasting effect than products that only mask odors temporarily.

What did the experiment with coffee and saliva show?

When coffee was mixed with saliva in test tubes, it blocked the creation of foul-smelling gases. Some tests showed up to a 90% reduction in bad breath-causing compounds, surprising researchers who expected the opposite result.

Are there coffee-based breath products available now?

Not yet. The research is still in development, with scientists working to isolate the specific compounds in coffee that fight bad breath for use in future oral hygiene products.

Recommended FrontStreet Coffee for Fresh Breath

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