Halitosis can happen to the best of us. Dentist and bacteriologist Dr Harold Katz explains the causes of and cures for bad breath, plus how to let someone know they have it without risking a relationship rift

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Bad breath: it’s a sensitive subject, made worse by the fact that it’s sometimes nigh on impossible to know whether or not you have it. There are the usual bad breath culprits that most of us are aware of, and obviously fastidious oral hygiene helps matters, but did you know that everything from taking  the contraceptive pill  to using certain types of toothpaste can trigger less than rosy breath? I for one did not, so in honour of World Oral Health Day, I quizzed dentist, bacteriologist and founder of The Breath Company  Dr Harold Katz on the ins and outs of bad breath, how to tackle it once and for all and ways to let someone down gently if their halitosis is having an impact. It’s a horrible conversation to have, but deep down we’d all want to know...

What constitutes bad breath

"Bad breath (or halitosis to give it its proper name) is the presence of a foul-smelling odour that is expelled from the mouth cavity. Unfortunately, bad breath is all too common a complaint, with an estimated one in four people in Britain reportedly suffering from the condition on a regular basis (NHS 2018)."

How to tell if you have it

"It can be difficult to tell if you are suffering with bad breath as it is often challenging to pick up on one’s own scent. Furthermore, family members, friends and colleagues may not feel comfortable in telling you. One of the best ways to establish if you have bad breath is by checking it yourself. Contrary to popular belief, you cannot check your breath by blowing into your hand. It simply doesn’t work. Your body is designed so that you cannot detect your own odour and your senses become used to the smell of your own breath. It’s a process called acclimation which we have developed over centuries of evolution – it helps us to be able to distinguish strange smells quickly without being overwhelmed by our own odours. You exhale your own breath constantly, so you become accustomed to your own smell.

"If you feel uncomfortable about asking the opinion of a trusted friend or family member, there are a few ways in which you can test your own breath. The first is ‘the cotton test’: wipe the top surface of your tongue with a piece of cotton gauze and smell it. If there’s a foul smell and a yellowish stain on the cotton, it's likely that you have an elevated sulphide production level and bad breath.

"You could also lick the back of your hand, leave it to dry for 5-10 seconds and then smell it, or run a piece of dental floss between your back teeth (this is the mostly likely place where you may get food caught) and then smell the floss. This may be an indication of the level of odours others detect. You can also stand in front of the mirror and stick your tongue out as far as possible. If you notice that the very back of your tongue is whitish, it may be a sign that you have bad breath.

Anyone can get bad breath, even people who are conscientious brushers and flossers

"The best way to truly identify the source of chronic halitosis is to visit a dentist or doctor for a professional diagnosis. When you are ready to tackle this situation, be sure to be open and honest with the healthcare professional performing the examination. It is important for them to understand all the health problems you are experiencing in order to determine the underlying cause and recommend appropriate treatment."

The most common causes of bad breath

"Anyone can get bad breath, even people who are conscientious brushers and flossers. It has less to do with oral hygiene (although that does have some impact) and more to do with things like food you eat, medications you take and lifestyle habits that you engage in that can provide an environment favourable to anaerobic, sulphur-producing, bad breath related bacteria.

"There are many underlying causes of bad breath, but the most common tend to be a dry mouth, often triggered by a lack of saliva through smoking, drinking alcohol, snoring and long periods of speaking to name but a few, as well as eating certain foods such as onions, garlic, curry, dairy, meat, fish and refined sugars and drinking coffee. Illness and disease can also be a factor."

What bad breath says about your general health

"It’s worth remembering that oral health is so much more than just about maintaining a great smile. The mouth is the entrance to our bodies and what we put in to it and how we treat it has an inextricable link to our overall health and general wellbeing.

"According to studies, an estimated 10 per cent of all halitosis cases are caused by certain illnesses. Individuals who suffer from  diabetes , lung disease, kidney disease, cancer, liver disease, respiratory tract infections, or metabolic disorders often experience chronic foul breath due to dry mouth. Sinusitis, pneumonia, bronchitis, post nasal drip, and polyps affect the airways and may also contribute to the problem. Other common illnesses associated with bad breath include nasal odour and tonsil stones, yeast infections of the mouth, and gum disease. Certain drugs such as antidepressants , high blood pressure medications, and antihistamines can factor into dry mouth because they reduce saliva production.

"Please note, however, that halitosis is rarely associated with life-threatening diseases. That said, it is important that you consult your doctor or dentist as soon as you notice consistent white spots on the tonsils and sores in the mouth with or without a fever. Sometimes bad breath is triggered by severe health conditions such as throat or mouth cancers, human immunodeficiency virus (HIV) infection, digestive system disorders, or diabetes, and it can indicate dehydration or zinc deficiency. Taking proper care of your teeth and visiting the dentist at least twice a year are the easiest ways to avoid these issues.

"Contrary to popular belief, bad breath does not come from the stomach.  There is no open tube connecting the large intestine, small intestine and stomach to your oesophagus and mouth. If you burp you may release smelly digestive gas - but that is not bad breath, it’s bad gas."

Halitosis and hormones

"Bad breath that is caused by food and bacteria doesn’t discriminate- incidences of halitosis are evenly split between the two sexes. However, there are certain hormonal triggers in women (such as birth control pills , pregnancy  and the menstrual cycle) that can cause mouth dryness which can lead to a higher prevalence of bad breath.

"In addition, as previously mentioned, lifestyle habits such as smoking and drinking alcohol excessively, as well as certain medications, can also increase the likelihood of developing bad breath so if you fall in to any of those categories then you will be more susceptible."

Products and ingredients to avoid

"Some toothpastes contains  sodium lauryl sulphate (SLS) , a soapy detergent that creates foam but has no cleaning benefit. The additive has recently been linked to serious side effects including canker sores.

"It’s important to steer clear of alcohol-based mouthwashes as these can cause dry mouth, and just mask odours rather than killing off bacteria.

"Regular and specific application of alcohol-free mouth rinses such as The Breath Company Healthy Gums Oral Rinse , £14.00 for 500ml, will help to calm the gum area and work to both eliminate germs associated with gum disease and reduce the formation of biofilm which leads to plaque and tartar build-up. Clinical tests of patients treated with The Breath Company rinses repeatedly resulted in a complete elimination of over 98 per cent of the volatile sulphur compounds that cause bad breath."

Foods to improve bad breath (and why some foods make it worse)

"Halitosis can be exacerbated by certain foods such as onions and garlic because they contain smelly sulphur compounds, while dairy, meat, and fish contain dense proteins which are used as a food source by the anaerobic, sulphur-producing bacteria. Refined and processed sugars also provide a food source for bacteria. Coffee and juices can contribute to this problem because they are acidic and provide these bacteria with an ideal breeding environment.

Try drinking green and black teas as they contain polyphenols that help to eliminate sulphur compounds and reduce oral bacteria

"Eating your five a day is really good for your oral health and high fibre foods  also help to prevent halitosis. Fresh produce contains vitamins and minerals that build strong and durable teeth, while other abrasive foods help to get rid of odour-causing plaque- think of it like brushing your teeth while eating. Fruits and veggies that are high in vitamin C help to reduce the plaque in your mouth as well and promote gum health, reducing the risk of gingivitis. Since these foods have a high water content, they promote saliva production in the mouth, which beats dry mouth and flushes away bad breath. Apples, celery and carrots, alongside other fresh produce will work to "brush" the teeth as they contain a high level of good starch that rinses away dental plaque and are rich in vitamins and nutrients that will keep gums healthy.

"Staying hydrated is also a key factor in keeping your mouth healthy. Dehydration is caused by not drinking enough fluid or by losing more fluid than you take in and can be caused by many factors including illness, sweating, excessive alcohol consumption, long-term health conditions and poor diet and exercise choices to name but a few. Dehydration can cause a range of oral health issues that include dry mouth, bad breath, cavities and gingivitis. You can try drinking green and black teas as they contain polyphenols that help to eliminate sulphur compounds and reduce oral bacteria."

How to (tactfully) tell someone that they have bad breath

"It’s important to remember that bad breath can really affect a person’s confidence and so it’s essential that you choose your words wisely and sensitively. Some chronic sufferers are completely unaware that they have bad breath as it is practically impossible to smell your own breath, so bear this in mind when you approach them. Choose a private setting to let them know, and only tell them if they can do something about it (if they have access to oral hygiene products for example).

"Be direct and use sensitively worded phrases such as “Sorry to mention this, but …”, “I wasn’t sure if you’re aware…” or something similar.

"If you are worried about offending someone then you could tell them anonymously by using the ‘tell a friend’ service available on www.thebreathco.com/tellafriend . The service allows you to send someone a friendly alert to tell them about their problem. They will be provided with accurate and valuable information on how they can eliminate this offending problem safely, affordably and effectively."

(Good luck).

Are you brushing your teeth all wrong?

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