Cheese (Cheddar)
Dairy · Cheese
Two slices of cheddar, about 40 g, contain 0.02 g of lactose and rate green. Cheese loses its milk sugar twice over: most drains away with the whey when the curd is separated, and the bacteria that ripen the block work through much of what survives. Hard cheese is the part of the dairy aisle that stays open to you.
Last updated 3 September 2026Serving sizes for cheese (cheddar)
The tested serve is 40 g, roughly two slices, rated green.
Tested serving sizes
| Serving | Amount | Main FODMAP | Rating |
|---|---|---|---|
| 2 slices | 40 g | Lactose 0.02 g |
Breakdown for 2 slices
Is cheese (cheddar) low FODMAP?
Lactose dissolves in the watery part of milk, so it goes wherever the whey goes. Draining the curd takes most of it out of the picture, and months of ageing let the cultures consume a good share of the rest, which is how the tested serve lands at 0.02 g — a small fraction of the 0.5 g mark where lactose begins to count as moderate. Set that against regular milk, where a 250 ml cup carries 7.5 g of lactose and rates red, and the scale of what draining and ageing achieve is obvious.
Cheese (Cheddar) and IBS: what to know
The same mechanism covers the firm end of the cheese counter. Parmesan and swiss are pressed, drained and matured in the same way, and both rate green in our guide, as does manchego. Fresh cheeses are the ones where portion size still does some work, because they hold on to more of the whey: ricotta and cottage cheese are made to stay moist, and moisture is where milk sugar lives. If cheese bothers you at these amounts, fat density is the more plausible suspect than the trace of lactose.
Gut-friendly ways to eat cheese (cheddar)
Cheddar earns its keep because it does the job of a high FODMAP ingredient without being one: grated over a jacket potato, melted through an omelette, or cubed with water crackers, it supplies the savoury depth people usually chase with onion. Two slices is a real serve rather than a token one, so a toastie or a cheese-topped bake fits inside it without arithmetic. The thing to watch is what the cheese turns up with — the bread underneath, the pickle beside it, the pasta sauce it disappears into.
Frequently asked questions
Is cheddar OK if I’m lactose intolerant?
Usually, yes. What survives draining and ageing is a trace rather than a dose, which is why hard cheese is often tolerated by people who can’t manage a glass of milk. Lactose intolerance is dose-dependent, so the practical limit is how much cheese you eat at once, not whether cheese is allowed at all.
Which cheeses are lowest in lactose?
The hard, aged ones: cheddar, parmesan, swiss, pecorino and manchego have all been drained and then matured, and the ripening cultures keep working on whatever lactose remains. Soft, fresh styles sit at the other end of that spectrum because they retain more whey, so they are the ones to keep an eye on the portion of.
Does mature cheddar have less lactose than mild cheddar?
It generally does. Both start from the same drained curd, but a cheese matured for eighteen months has given its cultures far longer to feed on the residual milk sugar than one sold at three months. The difference is small in absolute terms when the tested serve already sits at a trace, so either is a reasonable choice.
How much cheddar can I eat in one sitting?
Two slices (40 g) is the amount our data covers, and it rates green. A cheeseboard portion beyond that hasn’t been tested, so treat the tested serve as what you know rather than as a ceiling someone has proved. Richness usually decides it in practice: cheese is dense in fat, and large amounts feel heavy regardless of FODMAPs.
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