Most vegetables are low FODMAP at a standard serving of 75 grams (about ¾ cup). The key is knowing which ones to reach for freely, which ones need portion control, and which to avoid entirely. Here’s a practical breakdown to help you fill your plate with confidence.
What Makes a Vegetable Low FODMAP
FODMAPs are short-chain carbohydrates that ferment quickly in the gut, pulling in water and producing gas. In vegetables, the two main culprits are fructans (a type of fiber chain) and mannitol (a sugar alcohol). A vegetable earns a “low FODMAP” rating when a typical serving contains these compounds in amounts small enough that they’re unlikely to trigger symptoms in most people with IBS.
Serving size matters. A vegetable can be perfectly safe at ¾ cup but problematic at a full cup. The ratings below are based on testing by Monash University, the research group that developed the low FODMAP diet and maintains the most frequently updated food database.
Low FODMAP Vegetables by Category
All of the following are rated low FODMAP at one standard serve of 75 grams (roughly 2.65 ounces, or about ¾ cup). You can mix several of these in a single meal without worry, as long as each stays near its recommended portion.
Leafy Greens
- Lettuce (all common varieties)
- Spinach
- Bok choy
- Red and white cabbage
- Collard greens
- Kale
Leafy greens are some of the safest options on the diet. They’re naturally very low in fermentable carbohydrates, so portions are flexible.
Roots and Tubers
- Carrot
- Parsnip
- Potato
- Sweet potato
- Radish
- Yam
Potatoes and carrots are workhorses of a low FODMAP kitchen. They’re filling, versatile, and hold up well in soups, roasts, and stir-fries. Sweet potato is safe at a standard serve but contains some fructans at larger portions, so keep helpings moderate.
Fruiting Vegetables
- Eggplant (aubergine)
- Green bell pepper (capsicum)
- Cucumber
- Kabocha pumpkin
- Canned tomato
Pods and Others
- Snow peas
- Green beans
- Corn kernels
- Pickled beetroot
- Oyster mushrooms
Oyster mushrooms are a notable exception in the mushroom family. Most other mushroom varieties are high in mannitol and should be limited or avoided.
The Broccoli Exception
Broccoli is low FODMAP, but only certain parts of it. The heads (florets) are low FODMAP at a generous serving of one full cup. The stalks are a different story. They contain significantly more fructose and are rated high FODMAP at a typical one-cup serve. At half a cup, stalks drop back to low.
If you’re sensitive to fructose, trim away most of the stalk and use the florets. If you eat whole broccoli (heads and stalks together), a standard 75-gram serving is still fine. The practical takeaway: don’t make a meal centered on broccoli stalks alone.
Vegetables to Avoid or Limit
The highest FODMAP vegetables are rich in fructans, and most of them are the aromatic base of everyday cooking. The biggest offenders:
- Garlic (high in fructans, even in small amounts)
- Onion (all types: white, red, brown, shallots)
- Leek (the white bulb portion)
- Artichoke
- Spring onion / scallion (white part only)
Vegetables high in mannitol include most mushroom varieties (button, cremini, shiitake, portobello) and celery. These contain sugar alcohols that draw water into the intestine, often causing bloating and loose stools.
Fructans don’t dissolve in water and aren’t destroyed by heat, so cooking onions or garlic doesn’t reduce their FODMAP content. However, infusing oil with garlic and then removing the cloves is a common workaround, since the fructans stay in the garlic and the flavor compounds transfer to the oil.
Replacing Onion and Garlic Flavor
Losing onion and garlic feels like losing the foundation of most savory cooking. Fortunately, several low FODMAP vegetables and seasonings can fill the gap.
Green bell peppers add a savory depth, especially in Cajun-style dishes and stews. Fennel has a mild licorice note and an onion-like texture when sautéed, making it a strong stand-in for onion in chicken or fish dishes. The green tops of spring onions (scallions) are low FODMAP, even though the white bulb is not, so you can chop them freely as a garnish or stir-fry ingredient.
Beyond vegetables, fresh ginger works well in stir-fries, cumin can replicate some of garlic’s savory warmth, and freshly grated horseradish provides the pungent kick you might miss. Garlic-infused olive oil, as mentioned above, is one of the most effective shortcuts for getting garlic flavor without the FODMAPs.
How Serving Sizes and Stacking Work
A common concern is whether combining multiple low FODMAP vegetables in one meal causes their FODMAP content to “stack” and trigger symptoms. The short answer: at green-light serving sizes, this is unlikely.
Monash University designed its cutoff criteria conservatively so that people can include more than one safe-rated food per sitting. You can have carrots, spinach, and green beans in the same meal, each at a standard serve, without the FODMAPs accumulating to a problematic level. The general rule is that stacking concerns apply to a single sitting, assuming meals are spaced two to three hours apart.
Where stacking becomes relevant is when you eat unusually large portions of one food or combine many foods that all contain the same type of FODMAP. For instance, eating sweet potato, corn, and broccoli stalks together means three sources of fructose in one meal, and the combined load could push past your tolerance. Mixing different FODMAP types (one food with fructans, another with fructose, another with mannitol) is generally better tolerated than loading up on a single type.
Recent Changes Worth Knowing
Monash completed a full review of its vegetable category in July 2024, adding missing portion data and updating how fructose in vegetables is rated. This means some vegetables you checked a year or two ago may now have slightly different serving size recommendations. The Monash FODMAP app reflects these updates in real time and remains the most reliable way to check current ratings before shopping or cooking.
If you relied on an older printed list, it’s worth rechecking your staple vegetables against the current app data, particularly anything in the fructose-containing group like tomatoes, broccoli, and peppers.