Most commercial vegetable broth is not low FODMAP. The majority of store-bought brands contain onion and garlic as primary flavoring ingredients, and both are high in fructans, one of the main FODMAP groups. However, you can find or make a version that works on a low FODMAP diet if you know what to look for.
Why Most Vegetable Broth Is High FODMAP
Onion and garlic are the backbone of nearly every commercial vegetable broth. They show up in ingredient lists under various names: onion powder, garlic powder, dehydrated onion, roasted garlic. All of these are high FODMAP regardless of form. Celery, another broth staple, is high in mannitol and only stays low FODMAP at very small amounts (about a quarter of a medium stalk, or 12 grams). Leek bulbs are similarly problematic, with high fructan content that limits safe intake to roughly one to two teaspoons.
The real issue is that these FODMAPs don’t stay locked in the vegetables. Fructans from onion and garlic are water-soluble, meaning they leach directly into the liquid as it simmers. Monash University, the research group behind the low FODMAP diet, has confirmed that putting a whole onion or garlic clove into a broth and then fishing it out before eating does not make the broth safe. The fructans have already dissolved into the water. This is why even “clear” broths with no visible onion pieces can still trigger symptoms.
Reading Labels Carefully
If you’re shopping for vegetable broth, flip the container and scan the ingredient list before anything else. Watch for onion, garlic, leek (without specifying green parts only), celery in large amounts, mushrooms (high in mannitol), and artichoke. Also be cautious with vague terms like “natural flavors” or “spices,” which can hide garlic or onion derivatives.
At the time of writing, the only vegetable broth carrying official Monash University low FODMAP certification is Gourmend’s organic vegetable broth. Monash has also certified a small number of chicken and beef bone broths from Gourmend and Broth Sisters, which can serve as alternatives when you need a cooking liquid. If you can’t find a certified product, chicken or beef broth without added onion or garlic is generally a safer bet than vegetable broth, since plain meat is naturally FODMAP-free.
Making Your Own Low FODMAP Broth
Homemade broth gives you full control over ingredients, and the flavor can be surprisingly rich when you use the right vegetables. The key is choosing produce that’s naturally low or free of FODMAPs and building depth through other techniques.
Carrots and parsnips are both FODMAP-free and bring an earthy sweetness that forms a great base. The green tops of leeks and scallions are low FODMAP (up to about half a cup chopped for leek greens, or 54 grams) and deliver mild allium flavor without the fructan load of the white bulbs. Fennel bulb, a single celery stalk cut into pieces, and fresh herbs like thyme and bay leaves round things out. Some recipes also include potato or zucchini for body.
The biggest challenge is replacing the savory punch of garlic and onion. Garlic-infused oil is the standard workaround. Because fructans dissolve in water but not in fat, heating garlic cloves in oil transfers the flavor compounds without pulling fructans along. You can buy commercial garlic-infused oil or make your own, though food safety matters here: fresh garlic in oil can harbor dangerous bacteria if stored improperly. Use it immediately or buy a commercially prepared version. Drizzle the oil into your finished broth or use it at the start of cooking to build that familiar savory base.
A Basic Method
Combine chopped carrots, parsnips, leek greens, scallion greens, a stalk of celery, and fennel in a large pot. Cover with water, add a bay leaf and a few peppercorns, and bring to a boil. Reduce to a gentle simmer for 45 minutes to an hour. Strain out all the solids, stir in a tablespoon or two of garlic-infused oil, and season with salt. This freezes well in portioned containers for weeks of cooking.
Bone Broth and Other Alternatives
Plain bone broth made from chicken, beef, or pork bones is naturally FODMAP-free as long as no onion, garlic, or other high FODMAP seasonings are added during cooking. Many people on a low FODMAP diet use bone broth as their everyday cooking liquid and reserve vegetable broth for recipes where a meatless option matters. When buying bone broth, the same label-reading rules apply. Many commercial bone broths contain onion and garlic for flavor.
Miso paste (in small amounts), soy sauce, and a squeeze of lemon can also boost the savory quality of any broth without adding FODMAPs. These are useful tricks when your homemade batch tastes a little flat.
The Reintroduction Phase
If you’re in the elimination phase of a low FODMAP diet, strict avoidance of onion and garlic in broth matters most. But once you move into reintroduction, you may discover you tolerate small amounts of fructans. Some people find they can handle a commercial broth where onion appears far down the ingredient list (indicating a smaller quantity) without symptoms. Your threshold is individual, and structured reintroduction is the only way to find it. Until then, certified products and homemade broth are your safest options.