No — you cannot reliably 'beat' a properly calibrated breathalyser. The popular tricks (mints, pennies, breath-holding, coffee, hyperventilating) either do nothing or can make the reading worse. A modern fuel-cell device measures the alcohol leaving your blood, and only time reduces that.
Key facts
- No mint, coin, breath trick or drink reliably lowers a calibrated breathalyser reading.
- Breathalysers measure blood alcohol via breath — masking odour changes nothing.
- Only time reduces BAC; the body clears alcohol at roughly 0.015% per hour.
Myth: mints, gum or mouthwash mask alcohol
Reality: mints and gum only mask odour — they don't change the alcohol in your blood, which is what the sensor measures. Worse, many mouthwashes contain alcohol and can spike a reading. Masking your breath does nothing to the BAC.
Myth: sucking a coin or penny fools the sensor
Reality: this is an old urban legend with no scientific basis. Copper or any metal in the mouth has no effect on a breath-alcohol reading.
Myth: breath-holding or hyperventilating lowers the result
Reality: it can actually raise or lower the reading unpredictably — and not in your favour for evidential purposes. Holding your breath tends to increase the alcohol concentration in deep-lung air; hyperventilating may lower it slightly but is obvious to an operator and isn't a reliable 'escape'.
Myth: coffee, water or a cold shower sober you up
Reality: these may make you feel more alert, but they do not lower BAC. Your liver metabolises alcohol at a roughly fixed rate regardless of caffeine, hydration or temperature.
What actually affects a reading
- Time — the only real way BAC falls is by waiting.
- Mouth alcohol — testing within ~15–20 minutes of drinking can read high; protocols wait it out.
- Calibration & technique — accurate results require a calibrated device and a proper deep-lung sample.
- Medical/diet factors — rare conditions and certain substances can influence readings, which is why evidential testing follows strict procedure.
The responsible takeaway
There is no shortcut. If you've been drinking, the safe and legal choice is not to drive or operate machinery until enough time has passed — or until an accurate, calibrated test confirms you're clear.
Frequently asked questions
- Do breath mints or gum beat a breathalyser?
- No. They mask smell but don't change blood alcohol. Alcohol-based mouthwash can even raise the reading.
- Does holding your breath help?
- No. It tends to increase deep-lung alcohol concentration and won't reliably lower an evidential result.
- Can coffee or a cold shower sober you up?
- They may make you feel alert but do not lower BAC. Only time metabolises alcohol.