Hazelnuts are low FODMAP at a serving of 10 nuts, which is about 15 grams. That’s a small but meaningful portion, enough to add crunch to a salad or eat as a snack. Go beyond that amount and you risk moving into moderate or high FODMAP territory, where the fermentable sugars in hazelnuts can trigger digestive symptoms.
Why the Serving Size Matters
Hazelnuts contain oligosaccharides, a type of short-chain carbohydrate that ferments in the gut and can cause bloating, gas, and discomfort in people with IBS. At 10 nuts or fewer, the amount of these carbohydrates is low enough that most people tolerate them well. Once you exceed that threshold, the FODMAP load climbs quickly.
This makes hazelnuts one of the more restricted nuts on a low FODMAP diet. For comparison, peanuts are safe at up to 32 nuts per serving, macadamia nuts at 20, and chestnuts at 20. Almonds share the same tight limit as hazelnuts: 10 nuts or fewer. If you find yourself wanting a larger handful of something, peanuts or macadamias give you more room.
Hazelnut Spread and Other Products
Commercial hazelnut spreads (think Nutella-style products) have been tested and rated low FODMAP at a 20-gram serving, roughly one tablespoon. That might seem surprising given that these spreads often contain skim milk powder, which is high in lactose. But at such a small serving size, the lactose content stays low enough to be well tolerated by most people following the diet.
Watch out for added ingredients in flavored or store-brand versions. Some contain high fructose corn syrup, honey, or inulin (sometimes labeled as chicory root fiber), all of which are high FODMAP. Check the ingredient list before assuming any hazelnut spread is safe.
Hazelnut Flour in Baking
Hazelnut flour, sometimes called hazelnut meal, is popular in gluten-free baking. One dietary guide lists hazelnuts as suitable at up to 30 grams, though this appears to be a more generous threshold than the Monash University recommendation of 15 grams for whole nuts. The difference may reflect variation in testing methods or how the food is categorized.
If you’re using hazelnut flour in a recipe, the safest approach is to calculate how much flour goes into each individual serving of the finished product. A recipe that uses 100 grams of hazelnut flour and yields 8 servings puts about 12.5 grams of hazelnut per portion, which falls within the safe range. Recipes where hazelnut flour is the primary ingredient, like dense hazelnut cakes, can easily push a single slice past the limit.
Hazelnut Milk
Hazelnut milk is less widely studied for FODMAPs than almond or oat milk. Monash University has not published a specific rating for it, so there’s no confirmed safe serving size. The bigger concern with plant milks in general is what manufacturers add to them. Inulin, chicory root fiber, and other prebiotic fibers show up frequently in plant-based milks and are high in fructans, a FODMAP category that causes problems for many people. If you try hazelnut milk, choose a brand with a short, simple ingredient list and no added fibers or sweeteners like agave or honey.
Practical Tips for Staying Within Limits
Ten hazelnuts is easy to eyeball once you’ve counted it out a few times, but it’s worth being precise during the elimination phase of a low FODMAP diet when you’re trying to identify your triggers. A small kitchen scale helps. Fifteen grams is your ceiling for whole hazelnuts.
- Snacking: Pair your 10 hazelnuts with a low FODMAP fruit like a small banana or a handful of blueberries to make a more satisfying snack.
- Cooking: Chopped hazelnuts as a topping on oatmeal, yogurt, or salads are easy to portion. Sprinkle rather than scoop.
- Stacking: Be careful about eating multiple FODMAP-containing foods in the same meal. Ten hazelnuts alone are fine, but ten hazelnuts plus a serving of cashews (which are high FODMAP) could push your total load too high.
Roasting hazelnuts at home doesn’t significantly change their FODMAP content. You can toast them in a dry pan or oven for flavor without worrying that you’ve altered their digestibility in a meaningful way. The key variable is always quantity, not preparation method.