Garlic and Onion Substitutes for Low FODMAP Cooking
Garlic and onion are the two biggest hurdles on a low FODMAP diet, not because they're rare ingredients, but because they're the flavour base of an enormous number of everyday dishes. The good news is there are several reliable substitutes that let you keep that savoury depth without the symptoms.
Why Garlic and Onion Are High FODMAP
Both are high in fructans, a type of FODMAP that's poorly absorbed and easily fermented in the gut, which is what triggers bloating, cramping, and other IBS symptoms. Because fructans are water-soluble, even small amounts of garlic or onion powder can pack a bigger punch than you'd expect from the fresh vegetable.
The Best Substitutes
Garlic-Infused Oil
Fructans aren't oil-soluble, so when garlic is infused into oil, the flavour compounds transfer but the FODMAPs largely stay behind in the garlic solids, which are then strained out. This is the single most useful swap for anyone missing garlic flavour, it works in almost any recipe that calls for sautéing garlic as a base.
The Green Tops of Spring Onion
While the white bulb of a spring onion is high FODMAP, the green tops are low FODMAP and taste similar to a mild onion or chive. Sliced finely, they're a good finishing touch for dishes that would normally use diced onion.
Asafoetida (Hing)
Common in Indian cooking, asafoetida is used in small pinches as a savoury, umami-like substitute for garlic and onion. It's worth checking the specific brand, as some are bulked out with wheat flour, which may be relevant if you're also managing a gluten sensitivity.
Leeks (Green Tops Only)
Similar to spring onion, the green leafy part of a leek is low FODMAP, while the white base is not. Sliced and sautéed, the greens add a mild allium flavour to soups and stir-fries.
Chives
Chives are low FODMAP and can stand in for the fresh, oniony bite that garlic and onion would normally provide, particularly as a garnish.
Building Flavour Without Aromatics
Beyond direct substitutes, leaning harder into other flavour builders helps fill the gap left by garlic and onion:
- Umami-rich ingredients like fish sauce, soy sauce, or parmesan
- A well-balanced spice blend that doesn't rely on aromatics for its flavour base
- Acid (lemon, lime, vinegar) to brighten a dish that might otherwise taste flat
This is exactly the gap our blends are designed to fill - Essential Herbs, Mexican Spice, and Green Fusion are all built without garlic or onion powder, so the flavour comes from the spices themselves rather than the aromatics most recipes lean on.
Further Reading
For more on why garlic and onion specifically cause symptoms, read why some spices trigger IBS symptoms. And if you're just starting out, our beginner's guide to the low FODMAP diet covers the basics of the whole approach.
For confirmed serving sizes on any of these substitutes, Monash University's FODMAP app is the most reliable source.
Shop our full range of garlic and onion free spice blends.