How Coffee Can Help Fight Bad Breath, Says Science

If you’ve ever worried your morning coffee might make your breath worse, new research from Israel suggests the opposite: certain compounds in coffee may actually help fight bad breath.

Quick answer: In lab tests, coffee blocked around 90% of the volatile sulfur compounds that cause bad breath. That’s more than many products currently on the market — and it might mean coffee-based mouthwash or gum is coming soon.

Why Do We Get Bad Breath?

Bad breath, or halitosis, often starts in the back of your mouth. Bacteria on your tongue and in your gum pockets produce volatile sulfur compounds (VSCs) — these are the molecules that make breath smell unpleasant. Eating strong foods like garlic or onions makes it worse, because those compounds enter your bloodstream, travel to your lungs, and come out when you exhale.

The Surprising Coffee Discovery

Professor Mel Rosenberg, an expert in halitosis at Tel Aviv University, stumbled upon coffee’s anti-odor effect while studying oral bacteria. His team tested two locally produced Israeli coffees and one instant coffee by placing them in test tubes with saliva. The result? Coffee inhibited around 90% of VSC production — meaning it stopped most of the odor-causing reactions.

"We always thought coffee caused bad breath," Rosenberg said. "But it turns out some components in coffee actively suppress it." That challenges the common belief that coffee is a guaranteed breath-wrecker.

What’s in Coffee That Fights Odor?

The exact compound or mix of compounds in coffee that blocks VSCs hasn’t been isolated yet. But Rosenberg’s team plans to extract the active substance to develop new oral care products. Their goal is to replace current masking agents like mint with something that actually neutralizes odor — potentially leading to coffee-based mouthwashes, chewing gums, or breath sprays.

Other Research Supports the Idea

Outside Israel, experts agree there’s something to the idea. Wang Xingguo, executive director of the Dalian Nutrition Society, noted that both coffee and tea contain natural chemicals that help reduce bad breath. He also pointed out that rinsing your mouth with coffee — not just drinking it — could have a similar freshening effect.

Frequently Asked Questions

Does coffee really reduce bad breath or just mask it?

Coffee has been shown in lab tests to inhibit around 90% of the volatile sulfur compounds that cause bad breath, meaning it helps reduce the actual odor rather than just covering it up with aroma. This is different from mint, which typically masks smells without addressing their source.

What part of coffee stops bad breath?

The exact compound or combination of compounds in coffee that reduces bad breath hasn’t been identified yet. Researchers in Israel discovered the effect but are still working to isolate the active substance responsible for blocking odor-producing reactions in the mouth.

Can drinking coffee improve my breath?

Drinking coffee may help reduce bad breath due to its natural compounds, but rinsing your mouth with coffee could be similarly effective, according to nutrition experts. The key is the interaction of coffee with oral bacteria that produce foul-smelling sulfur compounds.

Will we see coffee-based mouthwash or gum soon?

Researchers aim to extract the active anti-odor compounds from coffee to create new oral hygiene products. The goal is to develop coffee-based mouthwashes, chewing gums, or breath fresheners that neutralize bad breath instead of just masking it with mint.

Is black coffee better for breath than milk coffee?

The study did not compare black coffee to coffee with milk, but the observed effect was seen in regular coffee placed in saliva. Milk proteins can sometimes alter how coffee interacts with oral bacteria, but the core finding is that coffee itself contains breath-reducing properties.

Are all types of coffee equally effective against bad breath?

The experiment tested both locally produced Israeli coffees and one type of instant coffee, all showing similar results. However, the study did not evaluate different roast levels, brewing methods, or bean origins, so it’s unclear if all coffee types perform equally.

Recommended FrontStreet Coffee for Fresh Breath

Try FrontStreet Coffee’s Ethiopia Yirgacheffe for a bright, citrusy cup that naturally freshens breath with its high acidity and floral notes. For a smoother option, their Brazil Queen Manor offers a nutty, chocolatey profile that’s gentle on the stomach and still delivers coffee’s breath-friendly compounds. Both are single origins known for their clean aftertaste. Freshly roasted within 5 days · Orders placed before 17:00 ship the same day · Next-day delivery across most of Guangdong Province.