By accident I discovered bad breath, and how to reduce it, in a particular group of people.
As a dietitian I helped people who suspected they were having adverse reactions to food investigate their diet. They often suspected they, or their children, reacted to foods high in additives, rich food, chocolate, herbs and spices, acidic fruit, or monosodium glutamate [MSG]. Over time I realized that suspect foods were usually high in flavour. The symptoms they often had included eczema and other allergic conditions, migraine and headaches, irritable bowel syndrome [IBS], and attention deficit hyperactivity disorder [ADHD].
A symptom many commented on was bad breath.
As I collected information about their reactions I often heard about their supersentivity to various smells. These included petrol products, cigarettes, strong perfumes, and foods they thought are “going off”. Since they are more sensitive to smell it is no surprise that they notice smells and comment on them in their family members. What was surprising was that I, and other researchers, found that on the elimination diet used to investigate possible food intolerance, bad breath was a symptom reported as reduced along with the main presenting symptom.
After 20 years of learning about food sensitive people I read with interest an article The science of bad breath in the Scientific American April 2002 issue. It considered research into what dentists and other scientists were finding. It discussed how sensitive some people with bad breath are to how others view them. It mentions that two compounds found in bad breath are putrescine and cadaverine. Fish odour syndrome was mentioned. It is due to the body’s inability to break down a chemical called an amine. One researcher reports that it is a lack of a sulphotransferase enzyme in the gut that allows amines to get into the bloodstream. Another reports that it is lack of a sulphotransferase in the kidney that prevents additive colours, flavours and natural salicylates [other suspect chemical groups] being broken down.
How did this apply to my patients?
Food sensitive people are the group who are likely to smell and be conscious of their breath smell as they are supersmellers. Because some people, usually only a few, often including relations, comment on their smell they think that everyone can smell their bad breath to the same degree. However it is likely that the supersmellers are only a small proportion of the community and so most people do not notice anything out of the ordinary.
Puterescine and cadaverine were of special interest to me.
They are among the amines that are produced in food as it ages and goes “off”. The names say it all! Food sensitive people often want to throw out food in the refrigerator as they are sure it smells “off”, when their friends or relations say there is no bad smell. But, as supersmellers they can detect these smells much better than others can. What is more, while they are on their low chemical elimination diet, if they avoid smells that smell stale to them they can reduce production of their particular symptoms.
How does this connect to the sulphotransferase enzyme problem? This was very interesting to me. I had been researching why food sensitive people react to additive colours, flavours, some preservatives, as well as another group similar shaped natural chemicals: salicylates, many more amines, and MSG. This work was frustrating! Those who worked in the area knew by gradual food testing just which foods were implicated in reactions. But why people reacted was not known. I noted that one sulphotransferase enzyme was used to metabolise, or “detoxify” amines. This includes the offensive smelling ones, as well as the usually attractive smelling ones in chocolate, red wine, aged meats, cheeses, and dark sauces. What tied it together was the finding that another sulphotransferase was used to metabolise the suspect additives and salicylates. Just who is food sensitive and what other possible mechanisms are involved is still complex and controversial.
How does bad breath and diet connect?
A group of people with bad breath are among those who appear to be slow metabolisers of all the aromatic compounds that are suspect in food sensitive people. Sulphotransferase enzymes are reported to lower in those with bad breath. Food sensitive people who investigate diet report that where bad breath was among the initial symptoms, it resolved when they responded to dietary investigation. In food sensitive individuals there can be a connection between what goes into the gut and bad breath because excretion of some compounds via breath is one way the body can rid itself of aromatic compounds from the blood, after they have been absorbed from the gut.
The big picture is even more interesting. It would take a whole book to cover all the other connected issues, such as bad breath not being the only body odour reported a problem, individuals differing in what they react to, and foods differing in their likelihood of causing reactions. See my book Tolerating Troublesome Foods, for the detail.
Overall what can we say?
Those with bad breath should have medical and dental investigation to exclude any problems that can be solved there. As well consider that bad breath often occurs in people who are food sensitive. This group of people are often supersmellers so they are more sensitive about the smell of their breath. Where they also have any of the usual food sensitivity symptoms they can investigate their diet, preferably with the help of a dietitian experienced in the area, and using my books. Where the diet produces reduction in other symptoms they often very pleased to also report a reduction in their bad breath.
Joan Breakey
I found this very interesting. I wonder whether some people who aren’t supersmellers and don’t know they are food sensitive, aren’t aware of their bad breath. A doctor I see has bad breath and I quietly mentioned it to one of his staff members. Not sure if she passed it on:-)! I am the mother of a supersmeller (I say she is like a sniffer dog:-), but this article helped explains why she won’t eat anything more than a day old sometimes. I didn’t put it down to taste or smell, just fussiness due to her hypersensitivity. Thank you.
Thanks for your comment Deb.
Supersmellers, such as your family are more aware of bad breath than others. This means that they notice others with bad breath, and like you, notice those whose bad breath will probably be noticeable to most people. You did the right thing bringing it to the attention of staff who may agree with you, but could not comment unless a patient reported it as a problem.
Your daughter noticing the smell change in food over one day is helping her avoid food that would be developing amines [which often aggravate headaches, migraine or gut pain, including crampy pain]. Each food sensitive person has their own cut off time. You have been a good mother realizing the time change as important for her. I like to advise food sensitive people that “Your nose knows!” including when you notice something about the food but others do not.
As a migraine sufferer I am extremely sensitive to smells. To the point of water coming from pipes in hotels… and I suspect greens in salads washed with thus water. (Novotel restaurant) I had to spit them out!
Just stayed at the Novotel in Brisbsne on creek street. Couldn’t stomach the water. But at a restaurant on the river, (Il Centro) who also said they were using tap water, I had no problem.
This is more than just the meats going off!!
Maybe the salad was one of those bagged salads and really was bad!
I’ve decided bagged salads is not worth the risk.
Maxalt is still my only saviour having tried the elimination diet for 10 weeks
Dear Beverley
Smells matter to most migraine sufferers. The smell that is most often detected in the water supply is chlorine. It is more often noticed here in the warm climate in Queensland. And it is more noticeable when coming from the hot water pipes. The important idea is that each smell sensitive person has smells that they react to more than others. As an example I met a man who could smell the plastic on a pool kick board quite a distance from him. Maybe you can detect something in the water pipes in one hotel but not the restaurant. If you react to bagged salads then avoid them, and test one some day in the future. And also think about the contents. Lots of smell sensitive people react to rocket and other lettuces with strong tastes. Do read the Article on What’s smell got to do with it? https://foodintolerancepro.com/category/food-intolerance/whats-smell-got-to-do-with-it/
Being so smell sensitive means that you are probably food chemical sensitive. Since I have been the dietitian most focused on smells and flavours the elimination diet you most need to use is the Baseline Diet in my book: Are You Food Sensitive? which is low in the suspect food chemicals, and includes the information from your Family Sensitivity History. When you go on the Diet Detective Diet you may be more smell sensitive for the first one or two weeks, but the good news here is that once established on the diet, smells decrease in their impact. This can make your life less distressing.
The next important idea is that you cannot tell if you are food sensitive by using a diet. It is by challenging after four weeks that you know, because you have a reaction to reintroducing foods from that baseline. It is important not to just stay on an elimination diet, especially one reducing fruit, which is necessary in this situation. As part of the challenges you reintroduce some or all of the suspect groups and find out which are important exclusions, which are useful but not essential, and which are no problem at all. There is also a chapter in Are You Food Sensitive? which describes doing challenges.
Of course even if diet has some role you still need to have a medication if you have a migraine. Maxalt is a saviour to many. Anyone using it should make sure they read all the fine print applying it to themselves.
I wish you well in your diet and smell detective work. Warm regards Joan
Hello i was reading your post as and ive been suffering with bad breath for years i dont know what it is since ive tried everthing .please help Jan
Dear Jan,
Lowering aromatic substances in your diet means less but different aromatic substances in your breath. Your enquiry meant I found detailed information on bad breath which I had written but had not put up on my site. Thank you for prompting me to add it to the Articles section so other people who are distressed by bad breath can be helped.
https://foodintolerancepro.com/bad-breath-distressing/
You will also be interested in the article ‘What’s smell go to do with it?’
Smell – What’s smell got to do with it?
https://foodintolerancepro.com/category/food-intolerance/whats-smell-got-to-do-with-it/
Food additives, salicylates, amines and MSG do not seem to have a lot in common until you look at the shape of the chemistry of the compounds and realize that many are what are called ‘aromatic’. Now you can investigate your diet using the diet detective process which I have gathered into my book Are You Food Sensitive? Get the help of a dietitian working in this area if you can as well. I wish you well in you finding a way to reduce bad breath. Warm regards Joan