Food matters: a nutritionist’s look at halitosis

Dietitian/nutritionist Anne Myers suggests your patients can find a way to fresher breath simply by changing their diet…

Halitosis is something that affects most people, briefly, at some stage in their lives but for others can be a distressing and ongoing problem. For hygienists and therapists working at the coalface, it can be a challenge in more ways than one. Dealing sensitively with the issue and being able to offer advice to reduce the problem can make the world of difference to the patient.

The most common cause of halitosis is poor oral hygiene. Accumulation of food debris and bacterial plaque results in gingivitis and periodontitis, resulting in malodour. Volatile sulphur compounds (VSCs) resulting from bacterial proteolysis, usually from gram negative bacteria located at the back of the tongue and in interproximal areas and periodontal pockets, are the main players in malodour production. This can be exacerbated by reduced saliva flow and conditions leading to a dry mouth. Smoking can also raise the concentration of volatile substances.

More than 90% of cases of halitosis originate from the oral cavity. There are, however, other possible causes of halitosis. These include upper respiratory infections such as bronchitis and sinusitis, certain medications and chronic medical conditions such as diabetes and renal disease. There have often been suggestions that digestive and bowel complaints may also have an impact on halitosis. In fact, the link between bowel disorders and halitosis has not been well supported. There is, however, reasonable evidence to support the link between halitosis and upper gastrointestinal disorders such as gastro-oesophageal reflux disease, (GORD), commonly seen in overweight patients.


Dietary factors and halitosis

Diet does play a role in both the cause and treatment of halitosis. Strongly flavoured, volatile foods such as spices, onions, garlic and coffee can cause transient halitosis and patients experiencing distressing halitosis from the intake of these foods should be advised to avoid such foods and drinks.Β  Sugary foods can also contribute to halitosis if excessive consumption results in tooth decay. Poor dietary habits contributing to obesity, GORD and the development of Type 2 diabetes can ultimately play a role in the development of halitosis. Sensible weight reduction should be recommended for patients who are overweight and obese.

Dietary composition can also play a role. It has been suggested that consuming dairy foods and foods high in protein can contribute to halitosis. The initial breakdown of dairy products in the mouth can lead to the release of sulphur rich amino acids. Care must be taken before advising removal of dairy products from the diet.

Oral hygiene practices following consumption of dairy and protein rich foods should first be recommended in patients who identify these as contributing to their halitosis. Following crash diets or high protein, low carbohydrate diets such as the Atkins or Dukan diet can also result in halitosis caused by the production of ketones. Regular water consumption should be advised for patients following these diets as this may help in reducing the odour.

Dietary advice and treatments

Ultimately, the best way to advise patients to avoid or treat halitosis is to concentrate on oral hygiene advice; including tongue cleaning.

There are also some dietary measures that can be put into place for reducing halitosis. Patients should be advised to follow a balanced diet and standard dietary advice for oral health should be given. Strongly flavoured food and drinks should be avoided. There are, however, a few additional dietary measures that may have an impact on halitosis.

A recent small-scale trial on intensive care patients using a mouthwash made from an essential oil mixture of diluted tea tree, peppermint and lemon found that the level of oral malodour following treatment with the mouthwash was significantly lower. It has been suggested, however, that mouthwash treatments are only a short term and masking solution.

Similar and more effective reductions have, however, been indicated with the daily use of green and peppermint tea. Tea polyphenols (tea catechins) can reduce VSCs in the mouth thereby reducing halitosis. Probiotics can also be potentially useful for reducing halitosis. A Japanese study using lactobacillus probiotics demonstrated a significant improvement in halitosis after only two weeks of being treated. Suggesting a probiotic drink each day may make an impact on halitosis. Dietary patterns can also have an impact on halitosis. Eating breakfast has been shown to make a difference with a study on senior school students reporting a lower risk of halitosis in students who regularly ate breakfast.

Foods, such as sugarless gum and sweets, which stimulate salivary flow, may have some benefit as can sipping water regularly. There are many dietary considerations that can be included when managing the patient with halitosis. Most recommendations can be put into place quite easily and without a negative impact on the patient. The benefits can be overwhelming for a patient suffering with what can be a socially distressing condition.

Diet is, however, only one factor in the development of halitosis. Oral hygiene and treating underlying medical concerns leading to halitosis should not be ignored.

Once any underlying problem is addressed, putting oral hygiene measures and dietary changes into place together could give your patients with halitosis a new lease on life.

β€’ References available on request


β€’ Poor oral hygiene

β€’ Smoking

β€’ Upper respiratory infections

β€’ Medications

β€’ Diabetes and renal disease

β€’ Gastro-oesophageal reflux disease

β€’ Obesity


β€’ Tongue cleaning

β€’ Avoid strongly flavoured food and drinks

β€’ Use a mouthwash made from an essential oil mixture of diluted tea tree, peppermint and lemon

β€’ Drink green and peppermint tea daily

β€’ Drink a probiotic drink each day

β€’ Eat breakfast as dietary patterns can also have an impact on halitosis

β€’ Eat sugarless gum and sweets that stimulate salivary flow

β€’ Sip water regularly


Anne Myers RD, BSc GradDipEd GradDipNut&Diet FHEA is a dietitian and nutritionist. She has extensive experience in many clinical areas and, more recently, as an advanced practitioner in diabetes, working in practice for 18 years. Anne works as a freelance consultant and as a lecturer in nutrition and dietetics and diabetes management. She is registered with the HPC, (RD) and is an Accredited Practicing Dietitian (APD – Aus).


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