Is grapefruit high in histamine?
Grapefruit is mostly low in histamine: two tested in Spain had none, but they averaged 55.55 mg/kg of putrescine, a related amine, and 6 of 10 published low-histamine diets exclude citrus.
- Histamine
- Not detected
- Other amines
- Notable levels
- Liberator
- Claimed, unproven
- DAO blocker
- No evidence
Why sources disagree. Grapefruit had no detectable histamine in lab tests, but it carries notable putrescine, a related amine, and six of ten published diets exclude citrus fruit as a group.
What each source says
| Source | Verdict | What it says, in our words |
|---|---|---|
| Lab measurements, Spain 1 | Measured | No detectable histamine in 2 grapefruits; putrescine averaged 55.55 mg/kg. |
| Juice study in the 2018 review 1 | Measured | Traces of histamine in some of 10 grapefruit juices, up to 1.74 mg/kg, put down to hygiene during processing or storage. |
| 10 published low-histamine diets 2 | 6 of 10 exclude citrus fruits. | |
| Review of low-histamine diets, 2020 3 | Suggests reactions to citrus may come from putrescine rather than histamine. | |
| Histamine-liberator claim 2 | Citrus fruits are listed among suggested histamine-releasing foods; no human study supports the claim. | |
| SIGHI food list 4 | See source | See SIGHI's own list for its rating. |
Measured histamine
| Food tested | Samples | Histamine | Other amines |
|---|---|---|---|
| Grapefruit sold in Spain 1 (Table 2) | 2 | not detected | putrescine mean 55.55 mg/kg (46.52–64.57); tyramine and cadaverine not detected |
| Grapefruit juice (another study) 1 (Table 2, row "Grapefruit Juice" (study [41])) | 10 | mean 0.31 mg/kg, range nd–1.74 mg/kg | putrescine mean 10.08 mg/kg (7.17–20.8); cadaverine mean 1 mg/kg; tyramine not detected |
| Citrus fruits sold in Spain (group) 2 (Table 1) | 38 | not detected | putrescine mean 79.75 mg/kg, up to 173.81 mg/kg |
mg/kg = milligrams of histamine per kilogram of food. "Not detected" means below the laboratory's detection limit.
How freshness and processing change it
Whole grapefruit keeps well, and no study we found showed histamine forming in the fresh fruit. Juice is where traces turned up: in one study of 10 grapefruit juices, histamine reached 1.74 mg/kg, and the authors linked it to hygiene during processing or storage, since the fresh fruit had none. Juice squeezed at home and drunk straight away is the closer match to the fruit.
No histamine in 2 samples; putrescine averaged 55.55 mg/kg. (measured)
Traces of histamine in some of 10 juices (up to 1.74 mg/kg); putrescine 10.08 mg/kg in that study and 98.6 mg/kg in another. (measured)
Why we rate grapefruit 1
Grapefruit is excluded from most low-histamine diets for being a citrus fruit, not for anything measured in grapefruit itself. Six of the ten published diets compared in a 2021 review exclude citrus fruit as a group. When a University of Barcelona team tested two grapefruits sold in Spain, neither had detectable histamine, tyramine or cadaverine.
What grapefruit does have is putrescine, the amine some researchers think competes with histamine for DAO, the gut enzyme that breaks histamine down. The two grapefruits averaged 55.55 mg/kg, and another study of two samples reported 51.1 mg/kg. That is less than oranges (91.24 mg/kg) and mandarins (90.16 mg/kg) in the Spanish survey, and far more than lemons (2.33 mg/kg). A 2020 review from the same group suggests putrescine may explain why some people react to citrus. The 2021 review notes that the evidence for this kind of competition comes from old laboratory and animal studies.
Juice is the one place histamine has turned up. A study of ten grapefruit juices found traces in some, averaging 0.31 mg/kg and reaching 1.74 mg/kg. Its authors concluded that histamine in grapefruit, orange and pineapple juices comes from poor hygiene during processing or storage, because the fresh fruit does not contain it. Even the highest juice value is below the 2.51 mg/kg average of fresh tomatoes.
We rate grapefruit 1, "mostly low", and mark it disputed. The putrescine and the wide exclusion of citrus each justify one step up from 0, and our rule allows only one. Two samples is a small set, so the citrus group figure (38 fruits, no histamine) is shown alongside it. If your dietitian has you off citrus during an elimination phase, follow that; if not, the measurements give no histamine reason to avoid fresh grapefruit.
One point that has nothing to do with histamine: grapefruit and its juice interact with a number of medicines. If you take any regularly, ask your pharmacist whether grapefruit is a problem for them.
Questions about grapefruit and histamine
Is grapefruit juice high in histamine?
No. One study of 10 grapefruit juices found an average of 0.31 mg/kg and a maximum of 1.74 mg/kg, which is low. The fresh fruit had none; the study's authors linked the traces in juice to processing and storage.
Why is grapefruit excluded from low-histamine diets?
Because it is citrus, and six of ten published diets exclude citrus fruit. Tested grapefruit had no histamine. The usual explanation is putrescine, which grapefruit contains at about 55 mg/kg; its effect on histamine breakdown has not been shown in people.
Evidence behind this page
- Two grapefruits sold in Spain had no detectable histamine, tyramine or cadaverine and averaged 55.55 mg/kg of putrescine; another study of two reported 51.1 mg/kg. 1
- In a study of 10 grapefruit juices, histamine averaged 0.31 mg/kg (up to 1.74); its authors attributed histamine in grapefruit, orange and pineapple juices to poor hygiene in processing or storage. 1
- Across 38 citrus fruits sold in Spain, histamine was not detected and putrescine averaged 79.75 mg/kg; six of ten published diets exclude citrus. 2
- A 2020 review suggests that symptoms after citrus may be due to other amines, especially putrescine. 3
- Citrus fruits appear on lists of suggested histamine liberators, but there are no clinical studies in humans supporting the idea. 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)
- 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)
- 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)