280-283 Propionic acid and its salts: the bread preservative

Vautism   See changes in the behaviour of laboratory rats given propionic acid, the common bread preservative.

E280 Propionic acid
E281 Sodium propionate
E282 Calcium propionate
E283 Potassium propionate*
cultured or fermented wheat, cultured or fermented dextrose or cultured or fermented whey (in fact, 'cultured' or 'fermented' anything!) - 'natural' preservatives which are chemically identical to added preservatives.

"If you wanted to create a nation of underperforming children, you could hardly do better
than to add a preservative known to cause learning difficulties to an everyday staple food"
- Sue Dengate


What are the effects of propionates?
How will I know if I am affected?
Reader stories
Isn't it important to keep our bread fresh?
Which countries use propionate preservatives?
How can I buy preservative free bread?
Why hasn't the bread preservative been properly tested before approval?
Scientific references
More information

Keywords: bread, propionate, preservative, propionic acid, sodium propionate, calcium propionate, potassium propionate, whey powder, cultured wheat, cultured dextrose, fermented wheat flour, fermented wheat, 280, 281, 282, 283, bread preservative, propionic acid, natural preservatives, propioniibacteria

*E stands for Europe – not used in Australia and New Zealand



Australia has one of the highest permitted levels in the world of propionic acid and propionates used as preservatives (E280-283).

Propionates occur naturally in small amounts in natural foods such as cheese and are also produced naturally in the human gut as part of the digestion process. In tiny amounts they are not harmful but, as with other additives, the effects are dose related. Very few consumers will be affected immediately by the amount of propionate preservative in one slice of bread but effects are cumulative, and can build up slowly over days or weeks, varying with the dose. This makes identification of the cause of symptoms extremely difficult.

Like all additives, this preservative was not tested before approval for its effects on children's behaviour and learning ability.

            What are the effects of propionates?

It is well known that very high levels of propionic acid are neurotoxic, due to their effects in children with propionic acidemia. This is a metabolic disease in which propionates cannot be broken down in the body due to an inborn enzyme deficiency, resulting in an accumulation of propionate in the blood. Complications can include learning disabilities, seizures, arrhythmia, gastrointestinal symptoms and recurrent infections and many others (Pena and Burton 2012, Schreiber et al 2012, Wajner and Goodman 2011).

Brazilian propionic acidemia researchers have produced similar effects – including learning disabilities due to 'chemically-induced propionic acidemia' (Brusque et al 1999) – in young rats by giving them propionic acid and have documented numerous effects of propionic acid (Pettenuzzo et al 2002, Trindade et al 2002, Fontella et al 2000, Brusque et al 1999, Wyse et al 1998) including an immunosuppression effect that could lead to low resistance to infection, accounting for the recurrent infections typical of propionic acidemia patients (Wajner et al 1999).
Canadian autism researchers have shown that higher than normal levels of propionic acid can accumulate in the circulating blood, cross the gut-blood and blood-brain barriers and can concentrate inside the cells where they may have adverse effects on brain development and function. As seen in the Autism Enigma documentary brief infusions of propionic acid in rats produced short bouts of behavioral (hyperactivity, perserveration, object fixation, social impairments) and other effects such as seizures, similar to those seen in Autistic Spectrum Disorders (Thomas et al 2012, Ossenkopp et al 2012, McFabe et al 2011, Thomas et al 2010, Shutlz et al 2009, Shultz et al 2008, McFabe et al 2007).
Australian food intolerance researchers were the first to report that propionate preservatives can contribute to hyperactivity in children (Swain et al). My own research in an Australian medical journal found that propionate preservatives can cause irritability, restlessness, inattention and sleep disturbance (difficulty settling to sleep and/or frequent night waking) in some children (Dengate and Ruben 2002).
Other reported symptoms include:
• migraine and headaches • gastrointestinal symptoms such as stomach aches, irritable bowel, diarrhoea • urinary urgency, bedwetting • eczema and other itchy skin rashes • nasal congestion (stuffy or runny nose) • depression, unexplained tiredness, foggy brain • speech delay, impairment of memory and concentration • tachycardia (fast heart beat) • arrhythmia • seizures • growing pains • loud voice (no volume control) • adult acne


     How will I know if I am affected?

Very few people realise they or their children are affected by this additive, because if you eat it every day, your symptoms will build up slowly or seem to come and go without any obvious cause. Some people notice a difference within days if they switch to preservative free bread. This is sometimes a sign that other additives and some natural food chemicals could be a problem too. Babies can be affected through breastmilk.

The best way to find out if you are affected is to switch to preservative free bread (genuinely preservative free – see our shopping list) for 3 weeks, then eat crumpets or several slices preserved bread every day for a week. Some people will see a reaction within days, for others it can take 5 days or more to build up.

            Reader stories

See 28 page collection of all reports on propionates

[207] 282: " very moody, stressed out and anxious" (September 2002)

I have always eaten a lot of bread, mainly wholemeal bread, muffins and bagels. I would often eat 6 English muffins a day. I used to get very moody, stressed out and anxious, in fact the people who I work with have asked me numerous times if everything is ok. I used to get very angry quickly and then in a split second I would feel like crying my eyes out. I also had an ongoing rash on my body, a feeling of ants crawling over my skin, was very tired and couldn't get up in the morning.

I really didn't want to be like this any more, so when I saw the previews on the telly about the bread preservative I watched with much interest, and decided to stop eating bread. Within a day I was feeling better, not irritable or anxious, and actually feeling happy, a change to how I normally feel. After three days I felt really different, better than I have for 6 or 7 years. Even my boss has said he's seen a huge change in me. I used to be a school teacher. If the kids in my class were feeling like I was, I can understand why they behaved the way they did. - Tim from Melbourne

From [329] 282: Two years of underachieving with calcium propionate (July 2004)

The introduction of preservative 282 in purchased bread coincided with a decline in our daughter's abilities. Her bread intake increased until she was eating about 8 or more slices/day and her performance decreased until we were able to get very little work out of her as she was unable to concentrate for more than about one minute at a time.

In desperation I called her teacher who mentioned the television report on 282. I did further investigation on the net, and read your site. The result was that we returned to using our bread maker after not having used it for nearly two years. After about ten days, we had a different child. She started concentrating! She finished in 10 minutes what she previously couldn't finish in 4 hours. Her spelling started to improve as did her handwriting. She also finally learned to ride a two-wheeled bike!

As you can imagine, we were thrilled. After two years of underachieving and barely being grade level, our daughter is finally starting to accelerate and achieve some of that potential. I am grateful we had the assessment as it shows how much she was behind. We have become very angry that this preservative is allowed ...- by email

[1096] 282: bread preservative causes bedwetting (February 2012)

In around Oct last year, my 8 year old son, who is usually dry at night, started wetting his bed. He wet it every night for over 2 months. During this same time, his twin sister – who has never been dry at night, went from wetting her bed once a night to wetting at least twice a night. Even their 3 year old brother, who was occasionally dry, stopped having any dry nights.

The first think I started to think about was what had changed in our diet, since it was something affecting all 3 of them. I was Googling away when I happened to come across your Food Intolerance Network site and the link between Calcium Propionate and bedwetting. I found a "what's in your bread" website (since we were in the car on a journey up to Scotland, and not at home) and discovered that the "healthy", Warburtons Seeded Batch Loaf which we had switched to about 2 months before contains 282. I have not used it, or any of the bagels or wraps (all with 282) we used to buy again and my son has not wet his bed once since then – apart from last Monday night. The children went back to school this week and go to an after school club on Mondays where they get sandwiches for a snack. I called the manager to find out what kind of bread they use – and sure enough, it is a long-life bread with 282. I explained all the dangers of this particular preservative to her and she was most willing to switch to a safer brand in future! – Michelle, UK

[958] 282: Mumbles and nosebleeds (October 2010)

About 4 weeks ago I removed 282 from my sons diet and he improved greatly, he would only speak in a mumble, he suffered from many nose bleeds in the week, was very negative about everything, not affectionate, didn't interact at preschool, would not co-operate at speech therapy. The change has been great he is talking so much more, he has not had a nose bleed since stopping 282, he is loving to everyone, he was great at speech did everything he was asked and sat still, interacts with others and notices things around him so much more - by email

[1165] 282: "I felt like a slug" (from 2004)

I'm only doing the elimination diet to keep my overactive son company, so I was very surprised at my own reaction to the bread preservative (282) challenge. After two days, I got so incredibly tired, I thought I was getting sick. All I wanted to do was sleep; I felt like a slug. Now, I have excessive energy normally so this was quite a change. When I stopped the bread I felt better overnight. - reader, USA

[1164] 282: Diagnosis of chronic fatigue really due to bread preservative (from 2002)

I am a busy executive. I love my job but for the last two years I have been feeling tired all the time and struggling to keep up. I was diagnosed with chronic fatigue. After I read your book I decided to try preservative free bread and GUESS WHAT? I don't have chronic fatigue after all - it was all due to that stupid preservative. People need to know it doesn't only affect kids. When I eat it, I feel tired and need to sleep a lot. - by email, WA

[121] Baby affected by bread preservative in breastmilk (August 2001)

I have a 10mth old baby boy who screamed for the first 3 and half months of his life all day and half of the night until my doc got me onto a dietitian and we tried the elimination diet. Every time I do food tests he reacts by screaming in agony within 24 hours and often gets a nasty red rash on his face and not so severe rash on his back and stomach. Before we tried the diet, we were hospitalised twice because I just couldn't cope. He reacts to most additives but the bread preservative is the worst and he also reacts very badly to amines. - Dani, WA

[121b] 282: Reactions range from temper tantrums to very moody

My daughter is nearly 5 years old. When we did the elimination diet we found that she reacts to the bread preservative, some other preservatives and MSG. Her reactions to the bread preservative range from temper tantrums to very moody pre-diet behaviour. This includes hitting and annoying her brother and sister if they are trying to do homework or just generally whingy and very demanding behaviour and refusing to do as requested. At night, she wakes up from 1 to 5 times per night and walks the house. When we put her back on to preservative-free bread her behaviour changed back to good behaviour within 3 or 4 days. – Moya, Qld

[338] 282: Urinary incontinence and asthma in seniors

We gave up 282 preservatives in bread after reading your book 'Fed up' about two years ago – within a week my wife was free of urinary incontinence and over a period of about three months I was able to give up all asthma medications. – readers aged 60 and 56

[204] 282: "one of my main triggers for migraine"

I am very interested in your research re calcium propionate. I thought that it may be of interest to you that as a migraine sufferer, I have found that 282 is one of my main triggers for a migraine attack. I have them very infrequently but very severely. By keeping a food diary I have been virtually able to avoid them. Calcium propionate has been off my list for at least five years. Thanks for drawing the attention of the world to the effects of this preservative. - by email

[1154] 282: seizures, extreme sleep disturbance, 'out-of-control' behaviour (October 2012)

I have a 2 year old son whose diet I have recently changed due to the behavioural problems that we were experiencing with him. My son was a big bread eater. While I was pregnant with him I was eating 10 slices of bread a day with 282 bread preservative and by the age of 18 months my son was eating the same amount. He was always a very difficult sleeper and has been having seizures since he was 18 months old. Since changing his diet to preservative free bread , he has gone from a monster to a reasonably placid child, he sleeps well, and his seizures have improved. Update after 6 months: since then, he has had only three seizures. – by email, NSW

[1155] 282: suspected epilepsy (memory lapses) (October 2012)

I thought you might be interested in this story from our group. One of the boys was exhibiting forgetfulness, inattention and memory lapses so noticeable that he was referred for brain investigation of suspected epilepsy. However, he never reached the tests - he stopped eating preserved bread first, and his problems stopped. – by email, Victoria

[711] Heart symptoms from 282 and other preservatives (December 2008)

My 14-year-old son has Aspergers syndrome. He experiences arrhythmia and severe heart palpitations every time he consumes any additives 211, 282, 220 etc. If he has been free from these additives for over two weeks then he will get away with the first exposure and then it accumulates and gets worse. We saw a heart specialist and he found no problems, just blaming it on anxiety. He also gets more aggressive and violent once it accumulates... like Jekyll and Hyde. Sadly it is so hard to convince and be believed by doctors and his psychiatrist that these additives affect him. – Therese, by email

From [197] 282: arrythmia

Thanks for interesting article on the effects of bread preservative. I went to my heart specialist a couple of weeks ago and told him I that when I eat bread, it makes the rhythm of my heart go absolutely crazy. It misses one beat in four and makes me feel quite unwell. He told me that was absolute nonsense, but he would get me to wear a 24 hour heart monitor. So I did that and when they analysed the data, sure enough, 35 minutes after I ate four slices of bread, the graph went wild. But he still doesn't believe that it was caused by bread. So I'm going to look for another heart specialist who will listen to me. - by email

[224] "After four weeks, he was able to go without medication altogether" (October 2002)

It's been 7 weeks now since we switched to Brumby's bread. Within days, my 10 year old ADHD son started improving and we halved his dose of dexamphetamine medication. After four weeks on preservative free bread, he was able to go without medication altogether.

You've no idea how much this child has changed. It's huge. I no longer get calls from school, he's bringing home merit awards, he entered himself in a maths competition, studied for it and won the first round . He does his homework without being asked. Half the time he goes to bed and is sound asleep before we say anything. Before, we used to get excited if he got to sleep by 11 pm. One day we were late for school and he said "that's OK, if we're late, we're late". Before, he would scream at me and kick the door. The change is unbelievable.

My older son has changed too. He is a very calm and loving child but he used to be so forgetful - like he was in another world. He would get very frustrated at forgetting things and sometimes he would snap. Now he remembers everything the first time.

We've seen improvements in the whole family - all five of us - except for the last two weeks, when we on holidays and we couldn't get Brumby's bread. We bought a bread labelled "no preservatives" but we all got worse. Then someone told me about whey powder. When I checked the label, it had whey powder in it.

My husband and I have noticed we have so much more energy and are less moody on preservative-free bread. With 282, I'm so tired all the time, I can't hold a conversation without losing people, my handwriting is terrible, I write some of my letters backwards, and I've even reversed phone numbers (02 instead of 20). This is really important in my job.

Three of us (me and two of the kids) are asthmatics. On the Brumbys bread we've all been asthma free and medication free for 3 weeks. That's a long time for us.

I'm angry. They think because they put a number on the label, they can put anything they like in our food. But we don't know what it is or what it can do to us. I don't want my child medicated if there's another way. - Anne-Marie, Hunter Valley, NSW

[1166] 282: Defiant, hyperactive, impossible to reason with, plain silly, very loud, noisy, annoying to others, demanding, pushy and tantrums (December 2012)

My daughter, who is now 7 years old and who began the failsafe approach at age 3, reacts in the following ways whenever she has 282 in bread. She becomes defiant, hyperactive, impossible to reason with, plain silly, very loud, noisy, annoying to others, demanding, pushy, and if something doesn't go her out...fully blown tantrum including slamming doors, storming out the house, screaming, yelling, crying that goes on for a long time. Can't and won't follow simple instructions, becomes distracted easily, goes off track and off task, becomes destructive She also finds settling at night really difficult ... can't seem to switch off. The next day she realizes that it was the 282 that made her feel that way ... and she genuinely can't refrain from behaving in this way. We are pleased though that as she grows her reactions seem to be becoming slightly less severe. I think this has to do with more careful diet, increased body weight, and increased maturity on her part.

Prior to going failsafe, life was unbearable. She had night terrors every night for 4 years etc, etc, etc. We made many trips to specialists and psychologists and others, with no explanation as to why we had a totally uncontrollable child. We chose to try Failsafe before we filled the prescription for Ritalin that we had been given, and thankfully it worked!

Thanks to your book, Fed Up, we have seen incredible results and are now on track. - Debbie, Victoria

[1163] 282: Grumpy and Rude, lacking concentration (from 2006)

I have been following the failsafe food guide and have had tremendous success. Today however after having a child for the past 3 weeks back to being Grumpy and Rude, lacking concentration, disruptive whenever possible and just not being nice, I discovered that the 'healthy' wraps we have been eating are now putting 282 in their product. After speaking to them they could not guarantee that 282 has not found its way into unmarked wraps.

We are not junk food people and have never encouraged that type of eating by our boys. We have found things that are considered the good foods affect our son and your books and information have helped us work out what he can and can not have. So when you find a product that has been great and they change it without telling you it is a pain and has had an effect on the whole family. Our son's teacher could not believe the negative change in him over the past 3 to 4 weeks towards his concentration and focus on his school work. - Cherie, Qld

[1162] 282: And oppositional defiance (June 2000)

I have recently joined the Failsafe Fan Club after watching the Current Affair special. You'll be pleased to know that all of my local bookstores immediately sold out of "Fed Up" and several orders were placed.

I was so frustrated to not be able to get my hands on a copy of the book, the symptoms that the children described were identical to things my daughter has been experiencing for the past year, voices in her head, a motor that never stopped running, hating herself and others, arguing with adults, and a worsening learning delay.

I logged on to your web page, read all the newsletters, made a manual list of all the readily available Failsafe products, printed off the additives to avoid, and immediately eliminated preservatives and colourings from my pantry and my shopping list.

The most obvious reaction has been the elimination of the bread preservative 282. We have had a breadmaker for 12 months now but had recently become lazy and had reverted back to using commercial breads. I could never understand how my daughter could be an angel for one whole day and then spend the next 5 days angry and sullen. The Reader's Stories showed me that preservative 282 could be the culprit. I am now only using Laucke's pre-mix in my breadmaker or commercial bread without 282. My daughter's Oppositional Defiant Disorder has disappeared within a week. My husband and I were so dumbfounded when we issued an instruction last weekend - expecting it to be completely ignored, followed by a stormy argument - to have my daughter jump up, reply "Yes, Mummy, sorry I didn't hear you the first time", carry out the task and then return to her play. We sat and looked at each with stupid grins on our faces for a full five minutes. - reader, by email

See a 28 page collection of success stories about 282, the propionate bread preservative

            Isn't it important to keep our bread fresh?

Contrary to what the food industry would like you to believe, these preservatives are not used to keep your bread fresh. Propionates 280-283 are added to inhibit the growth of mould. There is no mould on a freshly baked loaf of bread, so why use a mould inhibitor?

Bakers who keep their work benches and slicer blades clean and mould-free, by wiping with vinegar every day, do not need this additive. However, bakers in large factories prefer the less time-consuming method of fogging their equipment with a chemical spray. Putting hot loaves in plastic bags makes the problem worse. Preservatives 280-283 allow for sloppy hygiene. They are for the convenience of the manufacturer not the consumer.

            Which countries use propionate preservatives?

The use of calcium propionate (282) as a preservative in bread became widespread in Australia in the 1990s. Australia and New Zealand regulations permit a higher maximum level of propionate preservatives (E280-283) than anywhere else in the world, making Australian children more vulnerable to the side-effects of these additives. With the bread preservative most consumers do not realise what is affecting them and their children.

In Australia, propionates are now permitted in other products such as cheese or fruit juice but we have not yet received any complaints about these items. A mother in the US who was keeping her son on a propionate-free diet noticed a big reaction after a pizza. When she asked, they told her their pizza crusts were propionate-free but the cheese was "just loaded with it".

In the UK, until recently, propionate preservatives were used in only small amounts and sprayed on the crust, so you could avoid them by not eating your crusts. We presume that has changed, due to story 1096.

Propionate preservatives are appearing in countries around the world, including Asian countries, as their food becomes more Westernised. These additives may be disguised on the label as "with added calcium" – but calcium propionate is there as mould inhibitor NOT a calcium supplement.

            How can I buy preservative free bread?

It is currently relatively easy to find preservative free white loaves in most major supermarkets and hot bread shops but specialty breads are much more likely to contain preservatives. This includes:

- 'health' breads
- wholemeal breads
- rolls
- burger buns
- flat breads
- wraps
- gluten free breads
- crumpets

These seem to be the latest target for propionate preservatives and some readers have complained that they can't find any preservative-free gluten free bread or wraps.

Calcium propionate 282 is not the only bread preservative that can cause problems. Any of the propionates can cause the same effects and some people are also affected by other 200-number preservatives e.g. sorbates 200-203 and sulphites 223


• 280-283 propionic acid, propionates
• other 200-number preservatives
• cultured whey, wheat, rice or dextrose

Some bakers prefer to say 'all natural', so the food industry has created a dodgy method in which whey, wheat or dextrose can be cultured with propionibacteria to create propionate preservatives that don't have to be declared on the label.

"The pure acid or propionic salt must be labelled as a preservative when added to a food, thus precluding the use of the desirable term 'all natural' ... Alternatively, the propionibacteria may be grown in a natural medium such as milk or cheese whey and the entire medium ... may be dried and used as a natural preservative". - Glatz,1992

Avoid breads containing cultured wheat, cultured dextrose, cultured whey or whey powder even if marked 'preservative free' or 'no artificial preservatives'. This problem applies only to whey in bread and other bakery products such as croissants, and does not apply to whey powder in dairy products such as icecream.

How many ways is it being hidden?

We have identified that propionates can be shown as an ingredient called cultured OR fermented wheat, rice, whey or dextrose. That means there are 8 ways to hide propionates so far. Even "whey powder" was believed to be a cultured form to judge by a child's reactions, so that makes 9 ways and counting.


Take a quick quiz here to test your knowledge of the label above

See suggested brands – including gluten free - on our Failsafe shopping list /failsafe-shopping-list/bakery

Or make your own with a breadmaker.




            Why hasn't the bread preservative been properly tested before government approval?

No additives are tested for effects on children's learning, behaviour or health, despite a requirement under the Australian Food Standards Act for a scientific risk assessment. The food regulator FSANZ has even informed the Network that they would think it "unethical" to perform such tests on children.

Nor are additives tested on adults except for gross issues like cancer. Reports of side-effects from the these food additives, such as the huge range of learning, behavioural and chronic issues given on the front page of, are not accepted or collected by the food regulator.

Because there was no scientific evidence publicly available on the safety or otherwise of propionic acid and propionates used as a food additive, the Food Intolerance Network asked repeatedly for the evidence that had been used by FSANZ in their required assessment and approval process.

After being fobbed off with platitudes, a formal Freedom of Information request was lodged and resulted in the incredible response "that these documents do not exist" and then, later in the letter "currently available toxicological data supports the safe use of propionic acid ...." This was exactly the data which we sought, but it apparently both exists and does not exist! Full details of the Freedom of Information request and responses from FSANZ and Ministers.


Propionates are one of the most difficult additives to avoid because their use is widespread and they are in a healthy food eaten every day. In one generation, many Australians have gone from eating none of this preservative to eating it every day of their lives.

Currently, authorities are concerned about Australian students' poor performances on international tests. In 2012, a quarter of Year 4 students failed to reach the minimum standard in reading. Australia was placed 26th out of 45 participating nations in reading levels, lagging behind other English speaking countries except New Zealand.  What do Australia and New Zealand have in common? Their food regulations.

Twenty years ago, when more than 800 schools in New York City removed additives from free school lunches, the percentiles on national achievement tests improved 16% and the number of children classified as learning disabled halved. yet Australian children continue to tuck into their additives.

If you wanted to create a nation of underperforming children, you could hardly do better than to encourage the use of a preservative known to cause learning difficulties in an everyday staple food.

            Scientific references

American propionic acidemia research

Pena L, Burton BK. Survey of health status and complications among propionic acidemia patients. Am J Med Genet A. 2012 ;158A(7):1641-6.

Schreiber J, Chapman KA, Summar ML et al. Neurologic considerations in propionic acidemia. Mol Genet Metab 2012;105(1):10-5.

Brazilian propionic acidemia research

Wajner M, Goodman SI. Disruption of mitochondrial homeostasis in organic acidurias: insights from human and animal studies. J Bioenerg Biomembr. 2011;43(1):31-8.

Pettenuzzo LF, Schuck PF, Fontella F et al. Ascorbic acid prevents cognitive deficits caused by chronic administration of propionic acid to rats in the water maze. Pharmacol. Biochem. Behav. 2002;73(3):623-9.

Trindade VM, Brusque AM, Raasch JR et al. Ganglioside alterations in the central nervous system of rats chronically injected with methylmalonic and propionic acids. Metab. Brain. Dis. 2002;17(2):93-102.

Fontella FU, Pulrolnik V, Gassen E et al. Propionic and L-methylmalonic acids induce oxidative stress in brain of young rats. Neuroreport 2000;11(3):541-4.

Brusque AM, Mello CF, Buchanan DN et al. Effect of chemically induced propionic acidemia on neurobehavioral development of rats. Pharmacol. Biochem. Behav. 1999;64(3):529-34.

Wajner M, Santos KD, Schlottfeldt J et al. Inhibition of mitogen-activated proliferation of human peripheral lymphocytes in vitro by propionic acid. Clin Sci (Lond). 1999;96(1):99-103.

Wyse AT, Brusque AM, Silva CG et al. Inhibition of Na+,K+-ATPase from rat brain cortex by propionic acid. Neuroreport 1998;9(8):1719-21.

Brusque AM, Terracciano ST, Fontella FU et al. Chronic administration of propionic acid reduces ganglioside N-acetylneuraminic acid concentration in cerebellum of young rats. J. Neurol. Sci. 1998;158(2):121-4.

Australian propionate preservative research

Dengate S, Ruben A. Controlled trial of cumulative behavioural effects of a common bread preservative. J Paediatr Child Health. 2002;38(4):373-6.

Swain A, Soutter V, Loblay R et al. Salicylates, oligoantigenic diets, and behaviour. Lancet. 1985;2(8445):41-2.

Canadian autism research

Thomas RH, Meeking MM, Mepham JR et al. The enteric bacterial metabolite propionic acid alters brain and plasma phospholipid molecular species: further development of a rodent model of autism spectrum disorders. J Neuroinflammation. 2012;9:153.

MacFabe DF, Cain NE, Boon F et al. Effects of the enteric bacterial metabolic product propionic acid on object-directed behavior, social behavior, cognition, and neuroinflammation in adolescent rats: Relevance to autism spectrum disorder. Behav Brain Res. 2011;217(1):47-54.

Ossenkopp KP, Foley KA, Gibson J et al. Systemic treatment with the enteric bacterial fermentation product, propionic acid, produces both conditioned taste avoidance and conditioned place avoidance in rats. Behav Brain Res. 2012 ;227(1):134-41.

Thomas RH, Foley KA, Mepham JR et al. Altered brain phospholipid and acylcarnitine profiles in propionic acid infused rodents: further development of a potential model of autism spectrum disorders. J Neurochem. 2010;113(2):515-29.

Shultz SR, Macfabe DF, Martin S et al. Intracerebroventricular injections of the enteric bacterial metabolic product propionic acid impair cognition and sensorimotor ability in the Long-Evans rat: further development of a rodent model of autism. Behav Brain Res. 2009;200(1):33-41.

Shultz SR, MacFabe DF, Ossenkopp KP et al. Intracerebroventricular injection of propionic acid, an enteric bacterial metabolic end-product, impairs social behavior in the rat: implications for an animal model of autism. Neuropharmacology. 2008;54(6):901-11.

MacFabe DF, Cain DP, Rodriguez-Capote K et al. Neurobiological effects of intraventricular propionic acid in rats: possible role of short chain fatty acids on the pathogenesis and characteristics of autism spectrum disorders. Behav Brain Res. 2007;176(1):149-69.

Frye RE and others, Modulation of Immunological Pathways in Autistic and Neurotypical Lymphoblastoid Cell Lines by the Enteric Microbiome Metabolite Propionic Acid. Front Immunol. 2017 Dec 22;8:1670. doi: 10.3389/fimmu.2017.01670.

Korean research

Choi J and others Pathophysiological and neurobehavioral characteristics of a propionic acid-mediated autism-like rat model. PLoS One. 2018 Feb 15;13(2):e0192925. doi: 10.1371/journal.pone.0192925.

Food industry research

Glatz B. The classical propionibacteria: their past, present and future as industrial organisms. American Society for Microbiology News. 1992:58,(4):199-200.

            More information

Introduction to food intolerance
• Reader Reports - a 28 page collection of bread preservative reactions from readers:
Network campaign for preservative-free bread
Autism Enigma documentary (Australian Broadcasting Commission 2012)

Vautism   See changes in the behaviour of laboratory rats given propionic acid, the common bread preservative.

Probable propionates in cultured whey, wheat and dextrose labelled "no artificial additives"
Shopping for preservative-free bread
Recipe for preservative-free breadmaker bread with no added salt or fat

If you are a food manufacturer, there is a perfectly safe alternative: ethanol

Sue's blog - Bread preservative linked to obesity, diabetes

Sue's blog - Bread makes rats appear autistic

Sue's blog - Caution: “cultured dextrose”

Sue's latest blog - Harm from bread preservative confirmed (2021)

The information given is not intended as medical advice. Always consult with your doctor for underlying illness. Before beginning dietary investigation, consult a dietician with an interest in food intolerance. You can see our list of experienced and supportive dietitians 

© Sue Dengate update May 2021