In the 1990s and early 2000s, my family drank iced tea every day. We made it in large glass pitchers and kept it in the fridge.
We always used the same brand, which we bought from our local natural food store.Â
It tasted good on its own, so we never added sugar. I had no reason to assume it wasn’t healthy and safe.
Years later, I started learning more about how tea is grown and processed. I found multiple reports showing that tea can be contaminated with heavy metals, pesticides, and even mold.
Many of the teas most affected come from countries that still use chemicals banned in the U.S.
This concerned me, so I looked into the specific tea my family had used for years.
I checked where it was grown.
I contacted the manufacturer directly and asked if they tested for pesticides, heavy metals, or mycotoxins. Long story short, the answer I got wasn’t satisfactory.Â
Tea is one of the most chemically contaminated crops in the world.
Some tea-producing countries still use pesticides like DDT, which was banned in the U.S. in 1972 because of its links to cancer, hormone disruption, and neurological damage.
Tea leaves are dried—not washed—before packaging. That means any pesticide residue left on the leaves ends up in your cup.
Even organic teas can be contaminated if they are processed alongside conventional teas or not tested regularly.
There are no legal requirements for tea companies to test for these substances or to disclose their sourcing.
If a company doesn’t test, they can’t know whether their tea is clean. That was the case with the tea I used to drink. Once I realized that, I stopped buying it, even though it was a staple in our household—so much so that family and friends literally dubbed it “Burhenne Tea.”
If you think this is an argument against tea, it’s not.
Tea—when sourced and tested properly—is one of the best daily habits you can adopt for your oral health and microbiome (link to the one I drink).
Today, I drink green tea that has been tested for toxins and grown in regions with strict agricultural standards. I only buy from brands that provide third-party testing for pesticides, heavy metals, and mold.
Unlike most drinks, green tea supports oral health rather than harming it.
Here are three reasons I love green tea for promoting better oral health:
Green tea helps reduce harmful oral bacteria
It contains catechins, which target and suppress microbes like Streptococcus mutans and P. gingivalis.
These bacteria contribute to cavities and gum disease.
→ Study: Catechins inhibit oral pathogens
Green tea supports gum health
Studies show it reduces gum inflammation and slows the progression of periodontal disease, even when used with conventional treatment.
→ Study: Green tea improves periodontal outcomes
Green tea improves breath without harming the microbiome
It neutralizes volatile sulfur compounds, which cause bad breath, but does not kill beneficial bacteria like antiseptic mouthwashes do.
→ Study: Green tea reduces halitosis
Green tea also contains no sugar or acid. That means you can drink it throughout the day without feeding harmful bacteria or eroding your enamel. Compare that to soda, kombucha, or fruit juice!
Now, I only drink green tea that is well-sourced, and tested (link to the one I drink).
Green tea is one of my favorite things that I get to recommend as a dentist—because it doesn’t feel like a burden. It’s enjoyable. It has caffeine! You can drink it hot or iced. It supports your oral health without demanding discipline or adding another chore to your day. Unlike flossing—which, yes, I know many of you have come to love (and I love that)—green tea is easy to embrace.
If you’ve been here a while, you know how I feel about mouthwash—it wipes out your oral microbiome and is even shown to cause high blood pressure. I don’t recommend any mouthwash, even the “natural” ones because they contain essential oils which are disruptive to the oral microbiome.
But if you like the ritual of mouthwash, I do have a DIY green tea mouthwash recipe on my website. Green tea is the main ingredient—because that’s how powerful it is for your oral health.
– Dr. Mark Burhenne


P.S. Have you experienced something similar? Have you ever trusted something for years and later found out it wasn’t what you thought? Send me a reply. I’d like to hear about it.

