Is soy milk high in histamine?
Soy milk is low in histamine: three samples in a published study had none, and putrescine was low. It is the only plant milk measured in our sources, so the evidence is thin.
- 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 (study in the 2018 review) 1 | Measured | No detectable histamine or tyramine in 3 samples; putrescine averaged 1.02 mg/kg. |
| A second study in the 2018 review 1 | Putrescine 2.11 mg/kg and cadaverine 13.9 mg/kg in 2 samples; histamine not reported. | |
| 10 published low-histamine diets (2021 review) 2 | Soy milk has no bar on the chart; soybeans are excluded by 1 of 10. | |
| SIGHI food list 3 | See source | See SIGHI's own list for its rating. |
Measured histamine
| Food tested | Samples | Histamine | Other amines |
|---|---|---|---|
| Soy milk (study cited in the 2018 review) 1 (Table 1, row 'Soybean milk' (study [39])) | 3 | not detected | putrescine mean 1.02 mg/kg (0.39–1.81); cadaverine mean 0.28 mg/kg (nd–0.42); tyramine 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
The studies do not say whether the soy milk was chilled or shelf-stable, and none measured an opened carton. Keep an opened carton in the fridge and use it within the time on the pack. Soy yogurt and other fermented soy drinks were not measured.
No histamine in 3 samples; putrescine averaged 1.02 mg/kg. (measured)
Not measured; check the added ingredients. (estimate)
Why we rate soy milk 0
Soy milk is the only plant milk measured in the sources we use, and the measurement is small. A study by Toro-Funes and colleagues, one of those collected in the University of Barcelona team's 2018 review, tested three samples of soy milk. None had histamine or tyramine. Putrescine averaged 1.02 mg/kg, ranging from 0.39 to 1.81 mg/kg, and cadaverine 0.28 mg/kg. That is far less putrescine than in the soybeans themselves, which averaged 19.07 mg/kg in the team's own survey.
A second study, by Nishimura and colleagues, tested two samples. It reported putrescine at 2.11 mg/kg, which is low, and cadaverine at 13.9 mg/kg, which is not, and it gave no histamine figure. It is the same study that found unusually high cadaverine in onion and tofu, figures the 2018 review calls exceptions. With so few samples on either side, we rate from the study that measured histamine as well as the other amines, as we did for onion, and we show the second study in the sources so you can weigh it yourself.
For comparison, cow's milk had no histamine and none of the other amines the team measured in five samples. Oat, almond, rice and coconut drinks were not measured in our sources, so soy milk is the only plant milk with any data here.
Soy milk has no bar on the 2021 chart of foods excluded by ten published low-histamine diets; soybeans have one, excluded by one diet of the ten. Plain soy milk is not fermented, so the high histamine figures for fermented soy products do not apply to it. Soy yogurt is fermented and was not measured.
We rate soy milk 0, "low", on thin evidence: three samples tested for histamine, in one study. Plain, unflavoured soy milk keeps you closest to what was tested, and an opened carton belongs in the fridge.
Questions about soy milk and histamine
Is soy milk better than cow's milk for histamine?
Neither had detectable histamine in our sources. Cow's milk had none of the other amines measured in five samples; soy milk had a little putrescine in three. Both are rated 0.
Is soy yogurt low histamine?
Soy yogurt was not measured in the studies we use, so we do not rate it yet. It is fermented, and fermented soy products as a group were high in histamine, but those were different products.
Evidence behind this page
- Three soy milk samples in a study cited by the 2018 review had no detectable histamine or tyramine; putrescine averaged 1.02 mg/kg (0.39–1.81) and cadaverine 0.28 mg/kg. 1
- A second study of two samples reported putrescine at 2.11 mg/kg and cadaverine at 13.9 mg/kg in soy milk, without a histamine figure. 1
- Cow's milk sold in Spain had no detectable histamine or other biogenic amines (5 samples); soybeans averaged 19.07 mg/kg of putrescine. 2
- One of ten published low-histamine diets excludes soybeans; soy milk is not charted separately. 2
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)
- 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)