A 2025 Study Found Chewing Gum Can Shed Microplastics Into Your Saliva. Here's the Tree Resin People Are Chewing Instead.
Most gum is built on a synthetic "gum base." Chios mastic is one ingredient: resin from a tree on a single Greek island. Here's what the research says, and why it chews nothing like regular gum.
You chew gum for fresh breath. To focus. To keep your hands off snacks. Maybe just out of habit.
But flip the pack over. The first ingredient usually reads "gum base." That's it. No details.
In 2025, scientists finally checked what comes off that gum while you chew it.
What UCLA researchers found in saliva
The team, presenting at the American Chemical Society in March 2025, had a volunteer chew 10 popular gum brands, then tested the saliva for microplastics.
Sources: American Chemical Society press release, March 2025 · Lowe, Leonard & Mohanty, Journal of Hazardous Materials Letters, 2025 · UCLA Newsroom
Here's what we can tell you. US rules let a gum base include synthetic materials like polyethylene, polyvinyl acetate, butyl rubber and paraffin, and the label only has to say "gum base."
Source: 21 CFR 172.615, chewing gum base
So you're chewing something for 20 minutes a day, every day, and you can't see what it is.
Regular gum is soft by design. So it does almost nothing.
- Flavor dies in minutes. Then you're chewing rubber or reaching for another piece.
- Sweeteners and "flavors" come with almost every stick.
- No resistance. Your jaw barely works, so you get none of the "real chew" feeling.
That's why a growing number of people are going back to what Greeks chewed long before gum came in a wrapper.
Chios mastic: tree resin, not a synthetic gum base
Mastic is the resin of the Pistacia lentiscus tree. The kind with the long research record comes from Chios, a single Greek island, where farmers hand-collect it as it hardens into small "tears."
You warm a tear in your mouth for 20 to 30 seconds and it softens into a firm, natural chew. No wrapper. No gum base. The Classic Pack ingredient list has one line: Chios mastic resin.
90+ studies on Chios mastic. Here are the ones worth knowing.
Most gum has never been studied for anything. Mastic has a research record going back decades. We link every study, so you can read it yourself.
Listed by the European Medicines Agency as a traditional herbal medicine for mild indigestion. The listing is based on long-standing use.
In a double-blind, placebo-controlled study of 148 people with indigestion, 77% taking Chios mastic reported marked symptom improvement, vs 40% on placebo.
In a double-blind study, chewing mastic gum reduced plaque buildup on teeth compared with a placebo gum.
In a controlled study, chewing mastic gum for 15 minutes left significantly fewer S. mutans bacteria in saliva than a placebo gum, an effect seen up to 2 hours later.
In the placebo-controlled CHIOS-MASTIHA study, people taking 1 g of Chios mastic a day lowered total cholesterol by an average of 11.5 mg/dl in 8 weeks.
Studied since 1998 (NEJM). Mastic and H. pylori first appeared in the New England Journal of Medicine in 1998.
Digestive and cholesterol studies used mastic taken by mouth (capsules or powder), not chewed gum. Oral bacteria studies used mastic chewing gum. Study results describe the people studied and are not a promise of individual results. See all the studies.
A chew your jaw can actually feel
Mastic is firm. Where soft gum gives up in seconds, a mastic tear pushes back, so the muscles you chew with do real work every time you bite down.
One piece keeps its chew for a long time. Customers tell us they chew a single piece for hours, and it doesn't turn to mush.
That's why athletes chew it.
Athletes like Taylor Rapp chew Gum of Gods.
Why Gum of Gods, and not a cheap bag of mastic
Mastic is not new, and plenty of brands sell it. The common complaints are always the same: stale yellow crumbs, a sticky first chew, and a taste that's hard to get used to. We built Gum of Gods around fixing those.
| Regular gum | Cheap mastic | Gum of Gods | |
|---|---|---|---|
| Base | Synthetic "gum base" | Mastic | Chios mastic resin |
| Studied | No | Rarely says where it's from | Chios, the source in most mastic research |
| Pieces | Uniform sticks | Small, yellow, often stale | Large white tears |
| Storage | Paper wrapper | Plastic bag | Heat resistant pocket tin |
| Taste | Flavor gone fast | Plain resin only | Classic, Peppermint, Maple, Premium |
Rated 4.9 stars by 810 Classic Pack reviewers
"Having mastic gum daily has been a game-changer for me! Good jaw exercise and fresh breath!"
Bojan S., verified buyer"This is the best chewing gum. It's actually perfect for chewing. It really gives your jaw muscles a great workout. And you can save the gum in a glass of water and use it again and again."
Jeffrey G., verified buyer"I love this gum! It's natural and I always get the the highest quality pieces."
Ben G., verified buyer"After sucking on the hard resin for a while, It loosens up into a chewy substance that cleans your teeth and refreshes your whole body while also training your jaw"
Matthew M., verified buyer"Been chewing mastic for years. This is the absolute best mastic I have ever tried. Gum of Gods has perfected the flavoring and the taste is incredible."
Verified buyer, Maple Syrup PackReviews from verified buyers on gumofgods.us (Loox).
Get the 3-month plan →Your questions, answered straight
What does it taste like?
Plain mastic tastes fresh, woody and a little like pine. Some people love it on day one, others need a few pieces. If plain resin sounds intense, the Peppermint Pack is the easiest first chew.
Will it stick to my teeth or crumble?
Warm a piece in your mouth for 20 to 30 seconds before chewing and it softens instead of crumbling. If it gets sticky, sip cold water and it firms back up. That's normal for real resin.
Isn't $38.99 a month a lot for gum?
One piece lasts far longer than a stick of regular gum, and you can rinse and reuse it. On the 3-month plan it works out to about $1.30 a day, and you get free gifts worth $114 with it.
Is it safe with fillings or dental work?
Mastic is firmer than regular gum. If you have crowns, braces or loose fillings, ask your dentist first and start with short sessions.
Am I stuck in a subscription?
No. Cancel anytime. Questions? Call or text us at +1 (610) 549-4668.
The 3-Month Plan
- Free gifts worth $114 with your first order
- Prefer monthly? 25% off ($44.99/mo) + $64 in gifts
- Real Chios mastic, one ingredient
- Choose Classic, Peppermint, Maple or Premium
- Cancel anytime
*These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease. The microplastics figures come from a 2025 pilot study of commercial chewing gums; Gum of Gods mastic was not tested in that study. Digestive and cholesterol studies used oral mastic, not chewed gum.