
onion
Vegetables
Is onion high in salicylates?
Is onion high or low in salicylates? See its exact rating, how much counts as a portion, and its FODMAP, salicylate, oxalate and diet compatibility in one place.
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Sensitivity notes
Why salicylates food checker matters
Salicylates are natural chemicals found in many fruits, vegetables, herbs, and spices. They're related to aspirin and can cause reactions in sensitive individuals including hives, asthma symptoms, nasal congestion, and digestive issues.
- Start by eliminating the highest sources: spices, herbs, and concentrated products
- Peel fruits and vegetables when possible to reduce salicylate content
- Fresh is usually better tolerated than dried or concentrated
- Build up tolerance slowly by reintroducing foods one at a time
- Sensitivity often improves with gut healing over time
Sensitivities
What onion contains
FODMAPs
Histamine & Amines
Plant compounds
Irritants
Additives
Allergens
Diet fit
Where onion fits
Therapeutic diets
Lifestyle diets
Religious diets
What to know about onion
Onion is graded E for fructans and E for total FODMAPs, the top of our scale, which is why it is the single most common trigger people uncover once they start logging food against symptoms. The reaction is a carbohydrate problem rather than an allergy: onion is A for histamine, A for oxalates, A for lectins and A for nightshades, so if onion bloats you the fructans are almost certainly the mechanism. It also grades E for low fermentation SIBO plans. The frustrating part is that fructans are water soluble and heat stable, so caramelizing, slow simmering or fishing the pieces out of a sauce does not make onion any safer, and onion hidden in stock, gravy and spice blends is why so many people react to restaurant food they cannot account for.
Watch for
- Fructans and total FODMAPs both graded E, the highest tier we use, and the grade does not soften between raw and cooked onion
- Cooking is not a fix: fructans dissolve out of the onion into the pan and stay in the liquid, so straining the pieces out leaves the trigger in the sauce
- Hidden onion drives most unexplained flare-ups: stock cubes, gravies, curry pastes, spice rubs, chips and anything listed as seasoning or natural flavor
- Graded E for low fermentation SIBO, so onion is usually one of the first things pulled when working through a SIBO protocol
- Clean on the rest of the chemistry (histamine A, oxalate A, lectin A, nightshade A, with only a borderline B for histamine liberation), which is why an onion reaction is nearly always intolerance rather than allergy
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Salicylates Guide
Everything you need to know about salicylates sensitivity and smart food choices.
Salicylates are natural chemicals found in many fruits, vegetables, herbs, and spices. They're related to aspirin and can cause reactions in sensitive individuals including hives, asthma symptoms, nasal congestion, and digestive issues.
Sensitivity varies widely. What triggers one person may be fine for another. Track your reactions to find your personal threshold.
These foods are generally well-tolerated for Salicylates sensitivity:
View all safe optionsThese foods have moderate levels and may be tolerated in small amounts:
These foods are high in salicylates and may trigger symptoms:
View full listIf you're sensitive to Salicylates, consider these strategies:
- 1Start by eliminating the highest sources: spices, herbs, and concentrated products
- 2Peel fruits and vegetables when possible to reduce salicylate content
- 3Fresh is usually better tolerated than dried or concentrated
- 4Build up tolerance slowly by reintroducing foods one at a time
- 5Sensitivity often improves with gut healing over time
Pro tip: Keep a food diary to track your reactions. The Triggerbites app makes this easy with automatic pattern detection.
Want personalized tracking?
Download Triggerbites to log meals, track symptoms, and discover your unique triggers.
Get the AppFAQ
Is onion high in Salicylates?
Salicylates: moderate signal - portion size matters.
Can I still eat onion if I'm sensitive to Salicylates?
Try smaller portions and space it out.
What else should I check?
Check FODMAPs, Fructans, and Low Fermentation next for a fuller picture.





