Bad breath — where it comes from and what really works (and what just masks it)

Bad breath has one annoying feature: you cannot smell it yourself. You only find out from someone close to you, or not at all. And a second one: most "fresh breath" products do nothing for it other than add the scent of mint for thirty minutes.

In this text: what exactly smells, where it comes from, what you can do about it at home, and why we selected a toothpaste whose manufacturer provides test results instead of promises.

What is it that actually smells?

In about 85–90% of cases, the source is in the oral cavity. Anaerobic bacteria break down protein residues (from saliva, food, sloughed-off epithelium) and produce volatile sulfur compounds: hydrogen sulfide, methyl mercaptan, and dimethyl sulfide. These are responsible for the odor. Their biggest factory is the back of the tongue, where plaque stays the longest, and the gingival pockets in case of inflammation.

The rest are causes from outside the oral cavity: sinuses, tonsils, reflux, dry mouth from medications, diet, smoking. A toothpaste will not help with these, and it is worth knowing that right away.

Masking vs. eliminating the cause

Mint gum, spray fresheners, most drugstore mouthwashes: these are just a layer of scent placed over an odor. They work only as long as they last, which is from a few minutes to an hour. The alcohol in many mouthwashes also dries out the mucous membrane, and dry mouths smell worse, so after an hour, things can be even worse.

Eliminating the cause involves three things: fewer bacteria, less food for them, and neutralized sulfur compounds that have already formed. There is no single miracle ingredient here. A 2019 Cochrane review that compared various products for halitosis did not identify any method as definitively effective; the quality of evidence was rated as low. This does not mean that nothing works. It means you should look at the data for a specific product, not the slogan on the packaging.

What to do at home: order matters

• The tongue, daily. A tongue scraper or the back of your toothbrush, from back to front, a few strokes. This is one change that makes the biggest difference for most people, and it costs only a few dollars.
• Interdental spaces. Floss or interdental brushes once a day. Food particles between your teeth rot exactly as it sounds.
• Gums. If they bleed, it is inflammation, and inflammation has an odor. Professional cleaning at a hygienist's office, not another toothpaste.
• Hydration and saliva. Water throughout the day, xylitol gum after a meal when you cannot brush your teeth. Saliva is a natural mouthwash.
• Toothpaste and mouthwash without alcohol, so as not to dry out the mucous membrane. We write separately about when mouthwash makes sense here.

If the odor persists after two or three weeks of this routine, the cause is likely beyond the reach of a toothbrush. In that case, see a dentist, and then possibly an ENT specialist or gastroenterologist.

ANNAGIO: a toothpaste that shows the numbers

ANNAGIO is a brand from Trier, Germany, founded in 2020, whose formulas are developed in South Korea. It does one thing: it targets the causes of bad breath instead of masking it with mint. It made it into our selection for a simple reason: in the "fresh breath" category, almost no one publishes test results, but ANNAGIO does.

The heart of the toothpaste is a complex of 12 plant extracts (including green tea, eucalyptus, sage, myrrh, clove, chamomile) with xylitol and propolis. It works on three levels: it neutralizes volatile sulfur compounds, limits the bacteria that produce them, and leaves an herbal freshness that lasts longer than mint alone.

The manufacturer provides its own test results: after one 3-minute brushing, the level of hydrogen sulfide in exhaled air dropped by 91%, and methyl mercaptan by 96%; in an in vitro study, the number of Streptococcus mutans bacteria decreased by 86% after 5 minutes of contact. These are the manufacturer's tests, not an independent clinical study, and that is how we treat them. But that is still more than what most competitors show.

The rest of the ingredients are reasonable: 1450 ppm sodium fluoride (standard cavity protection), low abrasivity RDA 70, SLS-free (it uses mild sodium cocoyl glutamate), free from PEG, parabens, and titanium dioxide. The taste is intensely minty-herbal, with distinct notes of clove and eucalyptus. It is not vegan (propolis is a bee product).

Who is this a good choice for?

For those for whom drugstore mint stops working after half an hour and who want a fluoride toothpaste in a mild, SLS-free base. If you prefer a fluoride-free toothpaste, a sensible alternative for fresh breath is Ollie Strong Mint with its powerful menthol. If you suffer from recurring aphthous ulcers, be careful with clove and eucalyptus: they irritate the mucous membranes in some people.

Frequently asked questions

Is toothpaste enough to get rid of bad breath?

Not on its own. Most bacteria sit on the tongue and between the teeth, where toothpaste does not reach without a scraper and floss. Toothpaste is the third element, not the first.

How to use ANNAGIO for best results?

A pea-sized amount, 2–3 times a day, brushing for 2–3 minutes. The manufacturer also recommends cleaning the tongue and pulling the foam through the interdental spaces for 30–60 seconds before spitting.

When to see a doctor?

When the odor persists despite good hygiene for several weeks, or when it is accompanied by dry mouth from medications, heartburn, or sinus problems. Start with a dentist: they will rule out gum and tongue issues, and then refer you further.

Sources: Kumbargere Nagraj S. et al., “Interventions for managing halitosis”, Cochrane Database of Systematic Reviews 2019; Scully C., Greenman J., “Halitology (breath odour: aetiopathogenesis and management)”, Oral Diseases 2012; annagio.de (ANNAGIO manufacturer's materials and tests).