{"id":26020,"date":"2025-07-26T23:18:12","date_gmt":"2025-07-26T23:18:12","guid":{"rendered":"https:\/\/www.newsbeep.com\/uk\/26020\/"},"modified":"2025-07-26T23:18:12","modified_gmt":"2025-07-26T23:18:12","slug":"what-the-smell-of-your-breath-says-about-you-according-to-science","status":"publish","type":"post","link":"https:\/\/www.newsbeep.com\/uk\/26020\/","title":{"rendered":"What the smell of your BREATH says about you, according to science"},"content":{"rendered":"

By XANTHA LEATHAM, EXECUTIVE SCIENCE EDITOR<\/a> <\/p>\n

Published: 03:57 EDT, 26 July 2025 | Updated: 03:57 EDT, 26 July 2025 <\/p>\n

From the ridges on your fingernails<\/a> to the colour of your tongue<\/a>, there are plenty of signs that something might be wrong with your health.<\/p>\n

Now, an expert has revealed the smell of your breath is something to keep an eye on, too.<\/p>\n

Many might assume that bad breath \u2013 also known as halitosis \u2013 is the result of poor teeth cleaning or drinking too much coffee.<\/p>\n

However, research suggests breath odour may be an early warning sign of systemic health issues.<\/p>\n

Certain scents could indicate diabetes<\/a>, while others could point to liver dysfunction.<\/p>\n

‘Your breath can offer a surprising window into your health,’ dental technologist Allen Zhang said.<\/p>\n

He said there are five commonly overlooked types of breath that could signal a health issue.<\/p>\n

So, do you recognise any of them?<\/p>\n

\"Research <\/p>\n

Research suggests breath odour may be an early warning sign of systemic health issues, and not just the result of too many cups of coffee (file image)<\/p>\n

FRUITY OR ACETONE-LIKE<\/p>\n

This odour could indicate poorly-controlled diabetes, Mr Zhang explained.<\/p>\n

Research suggests that fruity-smelling breath can be a sign of high ketone levels in the blood, which can occur in individuals with the condition.<\/p>\n

Those affected might have breath that smells like pear drop sweets or nail polish remover.<\/p>\n

METALLIC<\/p>\n

This smell could suggest someone is suffering from kidney dysfunction or heavy metal exposure.<\/p>\n

This symptom arises when the kidneys are unable to effectively remove waste from the body \u2013 including urea, which forms ammonia when mixed with saliva.<\/p>\n

The presence of ammonia in breath can sometimes be perceived as having a metallic tinge.<\/p>\n

\"Mr <\/p>\n

Mr Zhang, a dental technologist, said certain odours are ‘diagnostic clues’ and ‘not just hygiene red flags’ (file image)<\/p>\n

What the smell of your breath says about you <\/p>\n

Fruity or acetone-like: Could indicate poorly-controlled diabetes<\/p>\n

Metallic: Could indicate kidney dysfunction\u00a0<\/p>\n

Fishy: Could indicate trimethylaminuria<\/p>\n

Rotten eggs: Could indicate\u00a0gastrointestinal issues\u00a0<\/p>\n

Musty: Could indicate kidney or liver issues\u00a0<\/p>\n

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Advertisement<\/p>\n

FISHY<\/p>\n

A fishy-smelling breath could indicate a condition called trimethylaminuria, Mr Zhang said.<\/p>\n

This is a metabolic disorder where the body cannot break down trimethylamine, a compound that smells like rotten fish.<\/p>\n

Fishy breath can also be a symptom of liver problems, specifically related to a condition called fetor hepaticus.<\/p>\n

Fetor hepaticus, often described as ‘breath of the dead’, arises when the liver is unable to properly filter certain toxins from the blood.<\/p>\n

These toxins, like dimethyl sulphide, can build up in the blood and be exhaled, causing the characteristic odour.<\/p>\n

ROTTEN EGGS<\/p>\n

Breath that smells sulphurous or like rotten eggs, can be an indicator of gastrointestinal issues.\u00a0The smell is called by hydrogen sulphide gas, which can be produced during digestion.<\/p>\n

MUSTY<\/p>\n

Finally, musty breath could mean there is something wrong with your kidneys or be a sign of liver failure.<\/p>\n

‘These are diagnostic clues and not just hygiene red flags,’ Mr Zhang said.<\/p>\n

‘New tech is emerging to help clinicians detect disease risk via oral biosignatures, including volatile sulphur compounds and ketones in the breath.’<\/p>\n

Mr Zhang is the founder of ProDENT<\/a>, a company developing intraoral imaging solutions for early detection.<\/p>\n

CAUSES OF BAD BREATH (HALITOSIS)<\/a><\/p>\n

There are a number of possible causes of halitosis:<\/p>\n

Poor oral hygiene<\/p>\n

This is the most common cause. Bacteria that build up on your teeth \u2013 particularly between them \u2013 as well as your tongue and gums, can produce unpleasant-smelling gases. These bacteria are also responsible for gum disease and tooth decay.\u00a0<\/p>\n

Food and drink<\/p>\n

Eating strongly flavoured foods, such as garlic, onions and spices, is likely to make your breath smell. Strong-smelling drinks, such as coffee and alcohol, can also cause bad breath.<\/p>\n

Bad breath caused by food and drink is usually temporary. Good dental hygiene will also help.<\/p>\n

Smoking\u00a0<\/p>\n

As well as making your breath smell, smoking stains your teeth, irritates your gums, and reduces your sense of taste.<\/p>\n

It can also significantly affect the development of gum disease, another major cause of bad breath.<\/p>\n

\"The <\/p>\n

The most common cause of bad breath is poor oral hygiene, although other reasons are food and drink, smoking and certain medications and medical conditions (stock image)\u00a0<\/p>\n

Crash dieting<\/p>\n

Crash dieting, fasting, and low-carbohydrate diets are another possible cause of bad breath. They cause the body to break down fat, which produces chemicals called ketones that can be smelled on your breath.<\/p>\n

Medication\u00a0<\/p>\n

These include: nitrates \u2013 these are sometimes used to treat angina; some chemotherapy medication; and tranquillisers (phenothiazines).<\/p>\n

If the medication you’re taking is causing bad breath, your GP may be able to recommend an alternative.<\/p>\n

Medical conditions<\/p>\n

In rare cases, bad breath can be caused by certain medical conditions. In dry mouth (xerostomia), the flow and composition of saliva may be affected.\u00a0<\/p>\n

Dry mouth can sometimes be caused by a problem in the salivary glands or by breathing through your mouth instead of your nose.<\/p>\n

In some cases, gastrointestinal conditions can also cause bad breath. For example, a bacterial infection of the stomach lining and small intestine (H. pylori infection) and gastro-oesophageal reflux disease (GORD) have been linked to bad breath.<\/p>\n

Other medical conditions that can cause bad breath include diabetes and lung, throat, or nose infections \u2013 for example, bronchiectasis, bronchitis, tonsillitis, and sinusitis.<\/p>\n

Halitophobia<\/p>\n

Some people are convinced they have bad breath when they don’t. This psychological condition is called halitophobia.\u00a0<\/p>\n

Source: NHS Choices\u00a0<\/p>\n

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