Ultra-processing markers
Bleached flour
Definition
What it is
Bleached or bromated flour: treated with chemical agents; potassium bromate is classified as a possible human carcinogen (IARC Group 2B) and is banned in the EU, Canada, and Australia.
On the label
How it appears on labels
- bleached flour
- bleached wheat flour
- chlorinated flour
Regulation
Regulatory status
- Australia/NZ Banned
- Brazil Banned
- Canada Banned
- European Union Banned
- Japan Banned
- United Kingdom Banned
Explainer
In plain language
Bleached flour is wheat flour treated with chemical agents to whiten it and improve baking performance faster than natural aging would. Agents like chlorine, chlorine dioxide, or benzoyl peroxide lighten the color and change the flour's protein and starch behavior. A related and more concerning treatment is bromation, which uses potassium bromate to strengthen dough.
Assessment
Why it is flagged
The main safety concern is not the bleaching agents themselves but potassium bromate, which is often grouped with treated flours. IARC classifies potassium bromate as possibly carcinogenic to humans (Group 2B) based on animal studies, and it is banned as a flour treatment in the EU, Canada, and Australia. The FDA has not banned bromate but encourages bakers to limit it, and California passed a law taking effect in 2027 to prohibit it. Chlorine-based bleaching agents raise fewer cancer questions but are part of why Clear Label groups these flours under ultra-processing. The key distinction is that bleached does not always mean bromated, so the severity depends heavily on which treatment a product used.
In the aisle
Where it commonly shows up
- White sandwich bread and rolls
- Cakes, cake mixes, and pastries
- Cookies and crackers
- Pie crusts and biscuits
- Some tortillas and flatbreads
- Bagged all-purpose white flour
Practical
Reading the label
Ingredient lists say 'bleached flour', 'bleached wheat flour', or 'enriched bleached flour'. Bromate is the one to watch: it appears as potassium bromate or 'bromated flour', and California-compliant products increasingly say 'unbromated'. Unbleached flour has been aged or left untreated but is otherwise similar.
Alternatives
If you want to avoid it
Some people choose products made with unbleached or unbromated flour, whole wheat flour, or breads that list only flour, water, yeast, and salt. Many bags of flour and many bakeries now state 'unbromated' or 'unbleached' directly.
FAQ
Common questions
Is bleached flour the same as bromated flour?
No. Bleaching whitens flour with agents like chlorine, while bromation strengthens dough with potassium bromate. The stronger safety concern is bromate, so it is worth checking whether a product is bromated separately from whether it is bleached.
Is bromated flour banned in the US?
Not federally as of 2026. The EU, Canada, and Australia prohibit potassium bromate, and California passed a law banning it in food sold in the state effective 2027, but the FDA still permits it while encouraging limits.
Why is potassium bromate flagged?
IARC classifies it as possibly carcinogenic to humans (Group 2B) based on animal studies. Most of it is expected to break down during baking, but residual amounts can remain if too much is used or baking is incomplete, which is why several countries chose to ban it.
Citations
Sources
Citation
Primary reference
About this page: the definition, label names, severity, and regulatory chips come from the clearlabel ingredient taxonomy, the same data the scanner uses to score products. Research summaries describe associations reported in published studies, not diagnoses; individual responses vary. Scan any product with clearlabel to see which of its ingredients carry flags.