Swiss cheese is low FODMAP and one of the safest cheese choices for people following a low FODMAP diet. A 40-gram serving (about 1.5 ounces) contains just 0.04 grams of lactose, which is well below the threshold that triggers symptoms for most people with IBS.
Why Swiss Cheese Is So Low in Lactose
The FODMAP in dairy products is lactose, a sugar that can cause bloating, gas, and diarrhea when it isn’t fully absorbed in the small intestine. During cheesemaking, bacteria consume most of the lactose as they ferment milk into curds. The longer a cheese ages, the more lactose gets broken down. Swiss cheese is aged for several months, which is why its lactose content drops to nearly zero.
Monash University, the research group that developed the FODMAP system, classifies a dairy product as low FODMAP when it contains 1 gram of lactose or less per serving. At 0.04 grams per serving, Swiss cheese comes in at a tiny fraction of that cutoff.
How Swiss Compares to Other Cheeses
Most aged, hard cheeses land in the low FODMAP category for the same reason Swiss does: the aging process eats up the lactose. Cheddar, Parmesan, Gruyère, Colby, and Gouda are all comparable options. Fresh, soft, or unripened cheeses tend to retain more lactose. Ricotta, cottage cheese, and cream cheese are higher in lactose and may cause problems depending on the portion size. Mascarpone and halloumi also fall into the moderate-to-high range.
A useful rule of thumb: the firmer and more aged the cheese, the less lactose it contains.
How to Check Any Cheese Using the Label
You don’t need to memorize a list of safe cheeses. The nutrition label tells you what you need to know. Look at the total carbohydrates and total sugars per serving. In cheese, virtually all the carbohydrate content comes from lactose. If both numbers are 1 gram or less per serving, the cheese qualifies as low FODMAP by Monash University’s standard.
Many low FODMAP cheeses will show 0 grams of carbohydrates on the label. That’s your simplest green light. If a cheese lists 2 or 3 grams of sugar per serving, it still has meaningful lactose and could trigger symptoms at larger portions. This label trick works for any brand or variety, so you can confidently evaluate cheeses you haven’t tried before without needing to look them up in an app.
Portion Size Still Matters
Even though Swiss cheese is extremely low in lactose, portion size is a factor on any low FODMAP diet. The tested low FODMAP serving is around 40 grams, roughly two thin slices or a small wedge. Eating a reasonable amount at a meal is unlikely to cause any issues. Eating several hundred grams in one sitting could, in theory, push lactose intake high enough to matter, though you’d need to eat an unusually large amount of Swiss cheese to reach that point.
If you’re in the elimination phase of the low FODMAP diet, sticking close to tested serving sizes gives you the clearest picture of your triggers. During the reintroduction and personalization phases, you’ll have more flexibility to experiment with larger portions.
Processed Swiss Cheese Products
There’s an important distinction between natural Swiss cheese and processed Swiss cheese products. Sliced “Swiss-style” cheese from the deli counter or pre-packaged processed cheese may contain added ingredients like milk solids, whey, or lactose itself as a filler. These additions can raise the lactose content well above what you’d find in a natural aged Swiss cheese. Always check the ingredient list for whey, milk powder, or lactose, and confirm carbohydrates on the nutrition panel. If the label shows more than 1 gram of sugar per serving, treat it with caution.
Block Swiss cheese from the cheese section, or any Swiss cheese labeled “natural,” is your safest bet. Imported Emmental, the original Swiss cheese, is aged and naturally very low in lactose.