Sue's Blog

Bread preservative linked to obesity, diabetes


My study about the effects of propionate bread preservative (280-283) on children’s behaviour was published in a medical journal in 2002.

Now a joint study between researchers in Israel and the United States has found that propionate plays a role in the metabolic process that could potentially contribute to the increase in obesity and diabetes. The Institute of Endocrinology at Sheba Medical Center is recognized as one of the top 10 hospitals worldwide by Newsweek.

I am not surprised. In my study, we found what we were looking for - irritability, restlessness, short attention span and sleep disturbance in children. But there were also reports from adults and children about “cravings” and “addiction” to preserved bread and many more: 

• migraine and headaches • gastrointestinal symptoms such as stomach aches, irritable bowel, diarrhoea • urinary urgency • eczema and other itchy rashes •  depression, fatigue, foggy brain • speech delay  • impairment of memory and concentration • tachycardia (fast heart beat) or arrhythmia • seizures • muscle pain

In the latest study, when researchers gave mice the same amount of propionate as is used in food, the mice gained weight and developed a resistance to insulin.

When they gave propionate to 14 healthy adults in a double-blind placebo-controlled study, those with the propionate showed higher levels of certain hormones, including glucagon, which works to raise the concentration of glucose in the bloodstream.

“The dramatic increase in the incidence of obesity and diabetes over the past 50 years cannot be attributed to genetic changes, and involves contributing environmental and dietary factors,” said lead author Dr. Amir Tirosh, director of the Institute of Endocrinology at Sheba Medical Center.

“One such factor that warrants attention is the extensive use of chemicals in the processing, preservation and packaging of foods. We are exposed to hundreds of these chemicals on a daily basis, and most have never been tested for their long-term metabolic effects.”

How to avoid propionate bread preservative

- avoid E280-283 (propionic acid, propionates)
- avoid “cultured dextrose”, whey, wheat or rice
- avoid “fermented wheat” wheat flour or rice
- don’t trust a label that says “all natural, no artificial preservatives” read the ingredient list

See more on our Propionate factsheet 

Reader stories

“My ex-husband … would often eat foods he was 'addicted to' (bread with 282 was his major addiction) “– from story [1231]

“I was diagnosed with chronic fatigue … 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 …” - from story [1164]

“We gave up 282 preservatives in bread…  within a week my wife [aged 56] was free of urinary incontinence” – from story [338]

“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 … [with]  a 24 hour heart monito … 35 minutes after I ate four slices of bread, the graph went wild …" - from story [197]

"I used to get very moody, stressed out and anxious …  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 … After three days [without preserved bread]  I felt really different, better than I have for 6 or 7 years … 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" – from story [207]

"The introduction of preservative 282 in purchased bread coincided with a decline in our 8 year old daughter’s abilities. Her bread intake increased … she was unable to concentrate for more than about one minute at a time …  we returned to using our bread maker after not having used it for nearly two years.  After about ten days [on preservative-free bread], we had a different child … She finished in 10 minutes what she previously couldn’t finish in 4 hours …" - from story [329]

More info

Tirosh A et al, The short-chain fatty acid propionate increases glucagon and FABP4 production, impairing insulin action in mice and humans. Sci Transl Med. 2019 Apr 24;11(489) - the Institute of Endocrinology at Sheba Medical Center is recognized as one of the top 10 hospitals worldwide by Newsweek.

Our bread preservative factsheet

Blog - Caution: “cultured dextrose”

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

Two failsafe wraps: MEB Foods Khobz Wholemeal Pita (Coles ) and Nana Premium Lebanese Bread White (Woolworths and of course the Mountain Bread range is all free of preservatives (Coles and Woolworths