January 6, 2026
Breath Wars: Bugs vs Buzz
Oral microbiome sequencing after taking probiotics
DIY saliva sequencing sparks breath paranoia and probiotic beef
TLDR: A blogger tested a $20 oral probiotic by mailing saliva for DNA checks and saw big day‑to‑day swings. Commenters split: skeptics roast miracle claims, DIY fans cheer the low cost, and one says probiotics rewired their “breath radar,” making this consumer‑biotech moment weirdly personal and worth watching.
A blogger swabbed spit, mailed it to Plasmidsaurus, and asked the internet: did a $20 mouth probiotic from BioGaia actually change their oral “bugs”? Cue breath paranoia and a comment section that reads like a reality show. Some were impressed BioGaia’s gut product has serious studies and even an FDA “Breakthrough” tag (for premature babies), but chorus line: that’s not the same as the mouth stuff.
Top drama: ravedave5 gasped at “a surprising amount of variation day to day,” turning the thread into a debate over whether your oral microbiome is basically a mood ring. temp0826 dropped a wild tale: BLIS K12 lozenges apparently reset their freshness radar, making them notice everyone else’s breath—now that’s a plot twist. net01 came in hot, side‑eyeing a different brand’s decades‑long claims to replace bad bacteria and brighten teeth; skeptics called it mouth snake oil with a minty label. SirensOfTitan shared a rough medical history, antibiotics wrecking their gut, and cautious curiosity about L. reuteri “yogurt.”
Meanwhile, biotinker cheered the DIY lab vibes: for about $240, you can run four samples and get week‑turnaround results. People joked about becoming “mouthfluencers,” and argued whether 5,000 “reads” (short DNA snippets) are enough—consensus: unless you’re hunting rare bugs, more is flex, not facts.
Key Points
- •BioGaia’s oral probiotic Prodentis contains L. reuteri DSM 17938 and ATCC PTA 5289 and is sold DTC at about $20 per month.
- •BioGaia cites over 250 clinical studies and has a $1B market cap; its spinout IBT’s IBP-9414 received FDA Breakthrough Therapy Designation in March 2025.
- •The author used Plasmidsaurus’s ONT-based 16S microbiome sequencing: $45 for ~5000 reads plus $15 for DNA extraction, with data returned in about a week.
- •Sample collection involved 100–250 µL saliva mixed with 500 µL Zymo DNA/RNA Shield; results included taxonomy tables, per-read assignments, plots, and FASTQ files.
- •Reported read metrics were median Q score 23 (~99%+ accuracy) and ~1500 nt read length; the experiment aimed to assess L. reuteri colonization after 30 days.