In the 1990s and early 2000s my family drank iced tea every day. We brewed it in large glass pitchers and kept it chilled in the refrigerator.
We always used the same brand from our local natural food store. It tasted fine on its own, so we never added sugar. At the time, I had no reason to suspect it might be unsafe.
Years later, after learning more about how tea is cultivated and processed, I discovered numerous reports showing that tea can be contaminated with heavy metals, pesticides, and even mold.
Many teas that test highest for contamination come from countries that still use chemicals banned in the United States.
Concerned, I investigated the specific tea my family had used for years. I checked its origin and contacted the manufacturer to ask whether they tested for pesticides, heavy metals, or mycotoxins. Their response left me unsatisfied.
Tea is one of the most chemically contaminated crops globally. Some producing countries still apply pesticides such as DDT—banned in the U.S. in 1972 because of links to cancer, hormone disruption, and neurological harm.
Tea leaves are dried—not washed—before packaging, so any residue on the leaves can end up in your cup. Even organic-labeled teas may be contaminated if they are processed alongside conventionally grown tea or if testing is inconsistent.
Currently, there are no legal requirements forcing tea companies to test for these substances or to disclose sourcing. If a company doesn’t test, it can’t know whether its product is clean. That was the reality with the tea I used to buy. Once I learned this, I stopped buying it, even though it had been a household staple—so much so that family and friends nicknamed it “Burhenne Tea.”
This is not an argument against tea itself. When tea is properly sourced and tested, it can be one of the healthiest beverages you drink daily—especially for your oral health and microbiome.
Today I choose green tea that has been tested for toxins and is grown in regions with strict agricultural standards. I only buy brands that provide third‑party testing for pesticides, heavy metals, and mold.
Unlike many other beverages, well-sourced green tea supports oral health rather than harming it. Here are three reasons I recommend green tea for better oral health:
Green tea reduces harmful oral bacteria
Green tea contains catechins that target microbes such as Streptococcus mutans and Porphyromonas gingivalis. These bacteria contribute to cavities and gum disease, and catechins help suppress their growth.
Green tea supports gum health
Clinical studies indicate green tea can reduce gum inflammation and slow the progression of periodontal disease, especially when used alongside conventional treatment.
Green tea freshens breath without damaging the microbiome
Green tea helps neutralize volatile sulfur compounds—the main cause of bad breath—while leaving beneficial oral bacteria intact, unlike antiseptic mouthwashes that broadly wipe out microbes.
Green tea also has no added sugar and is less acidic than many popular drinks. That means you can sip it throughout the day without feeding harmful bacteria or eroding tooth enamel, unlike soda, kombucha, or fruit juice.
Because of these benefits, I stick to green tea that is transparently sourced and independently tested.
As a dentist, recommending green tea feels natural: it’s enjoyable, contains some caffeine, and can be consumed hot or iced. It supports oral health without requiring extra effort or becoming another chore—unlike certain habits people struggle to maintain.
If you enjoy the ritual of a mouthwash, consider a green tea–based rinse. I prefer to avoid conventional mouthwashes because many wipe out the oral microbiome and have been linked in some studies to unintended health effects. A simple green tea rinse preserves beneficial microbes while helping control odor and inflammation.
– Dr. Mark Burhenne
P.S. Have you ever trusted a product for years only to discover it wasn’t what you thought? I’d love to hear your experience—send a reply and tell me about it.
