Are oats high in histamine?
Oats are low in histamine: oats sold in Spain had none and only 0.67 mg/kg of putrescine, and 28 cereal samples averaged 0.12 mg/kg. Oat milk was not measured.
- Histamine
- Not detected
- Other amines
- Low
- Liberator
- Not on the lists we use
- DAO blocker
- No evidence
What each source says
| Source | Verdict | What it says, in our words |
|---|---|---|
| Lab measurements, Spain 1 | Measured | No detectable histamine in oats; putrescine averaged 0.67 mg/kg. |
| Review of low-histamine diets, 2020 2 | Measured | 28 cereal samples averaged 0.12 mg/kg of histamine, none above 0.89 mg/kg. |
| 10 published low-histamine diets 3 | Oats are not on the review's chart of foods the diets exclude. | |
| SIGHI food list 4 | See source | See SIGHI's own list for its rating. |
Measured histamine
| Food tested | Samples | Histamine | Other amines |
|---|---|---|---|
| Oats sold in Spain 1 (Table 3) | 2 | not detected | putrescine mean 0.67 mg/kg (0.44–0.89); tyramine and cadaverine not detected |
| Cereals (group) 2 (Table 1) | 28 | mean 0.12 mg/kg, range nd–0.89 mg/kg | median not detected |
mg/kg = milligrams of histamine per kilogram of food. "Not detected" means below the laboratory's detection limit.
How freshness and processing change it
Dry oats keep well and had no histamine. Porridge made fresh is the closest match to what was measured. Overnight oats, soaked in the fridge rather than fermented, and oat milk were not measured.
No histamine in oats; cooking does not create it. (measured)
Why we rate oats 0
Oats are among the lowest-amine foods in the University of Barcelona team's tables. Oats sold in Spain had no histamine, tyramine or cadaverine, and their putrescine averaged 0.67 mg/kg, one of the lowest figures the team recorded for any plant food. The 2018 review that reports these figures explains why grains look like this: in principle they contain no amines other than putrescine, and that putrescine comes from the plant itself rather than from bacteria.
The Spanish figure comes from only two samples, which is too few to rely on alone. The cereal group figure from a 2020 review by the same team covers more ground: 28 cereal samples averaged 0.12 mg/kg of histamine, and the highest single sample had 0.89 mg/kg. Both point the same way.
Oats do not appear among the foods charted as excluded by the ten low-histamine diets in the team's 2021 review. Because that chart covers only some foods, we say that no diet in our sources excludes oats, not that all ten allow them.
We rate oats 0, "low". Porridge or oats cooked fresh are the closest match to what was measured, because cooking does not create histamine. Overnight oats are soaked in the fridge rather than fermented, so they are unlikely to differ much, but they were not measured. Oat milk is a processed drink and was not measured either.
Oats are often mentioned alongside gluten. Pure oats contain little or no gluten but are often grown and milled next to wheat. That matters for coeliac disease, a separate condition from histamine intolerance; this rating says nothing about gluten.
Questions about oats and histamine
Is oat milk low in histamine?
Oat milk was not measured in the studies we use. Oats themselves had no histamine, but oat drinks are processed and stored, so we do not carry the rating over.
Are overnight oats low in histamine?
They were not measured. They are soaked in the fridge, not fermented, so we would not expect much histamine, but there is no data to confirm it.
Evidence behind this page
- Oats sold in Spain had no detectable histamine, tyramine or cadaverine; putrescine averaged 0.67 mg/kg (0.44–0.89). 1
- Cereals contain no amines other than putrescine, which has a physiological origin. 1
- Across 28 cereal samples, histamine averaged 0.12 mg/kg, with a maximum of 0.89 mg/kg. 2
- Oats do not appear among the foods charted as excluded by ten published low-histamine diets. 3
Sources
- Sánchez-Pérez S, Comas-Basté O, Rabell-González J, Veciana-Nogués MT, Latorre-Moratalla ML, Vidal-Carou MC. Biogenic Amines in Plant-Origin Foods: Are They Frequently Underestimated in Low-Histamine Diets? Foods 7(12):205, 2018. doi:10.3390/foods7120205 (Sánchez-Pérez S et al. 2018)
- Comas-Basté O, Sánchez-Pérez S, Veciana-Nogués MT, Latorre-Moratalla M, Vidal-Carou MDC. Histamine Intolerance: The Current State of the Art. Biomolecules 10(8):1181, 2020. doi:10.3390/biom10081181 (Comas-Basté O et al. 2020)
- Sánchez-Pérez S, Comas-Basté O, Veciana-Nogués MT, Latorre-Moratalla ML, Vidal-Carou MC. Low-Histamine Diets: Is the Exclusion of Foods Justified by Their Histamine Content? Nutrients 13(5):1395, 2021. doi:10.3390/nu13051395 (Sánchez-Pérez S et al. 2021)
- Swiss Interest Group Histamine Intolerance (SIGHI). Food compatibility list for histamine intolerance. histaminintoleranz.ch (accessed November 2026), 2026. Link (Swiss Interest Group Histamine Intolerance (SIGHI) 2026)