A standard one-ounce slice of American cheese contains roughly 0.1 to 1 gram of lactose, though some sources cite a wider possible range of 0.5 to 4 grams depending on the product. That puts it well below the 12 grams found in a cup of milk, making it one of the lower-lactose dairy options available.
Why the Range Varies So Much
The lactose content of American cheese depends heavily on what you’re actually buying. “American cheese” covers a spectrum of products, from pasteurized process cheese (made primarily from real cheese) to pasteurized process cheese product (which contains more added ingredients like whey, milk solids, and emulsifiers). The more milk-based additives in the recipe, the more lactose ends up in the final product.
Penn State Extension lists processed American cheese at about 0.11 grams of lactose per slice. The USDA’s nutrition data for sliced American cheese shows 1 gram of total sugars per ounce (and in cheese, virtually all sugar is lactose). UpToDate, a medical reference database, gives a broader range of 0.5 to 4 grams per ounce for pasteurized processed American cheese. The takeaway: a name-brand slice from the deli counter and a generic individually wrapped single are not the same product, and their lactose content reflects that.
How American Cheese Compares to Other Cheeses
Natural aged cheeses tend to have less lactose than American cheese because the aging process gives bacteria more time to consume the milk sugars. Cheddar contains about 0.07 grams per ounce. Mozzarella is even lower at roughly 0.04 grams per 50-gram serving. Swiss, Brie, and blue cheese also fall into the very-low-lactose category.
American cheese sits slightly higher because it’s a processed product, not a traditionally aged one. During manufacturing, cheese is melted down and blended with emulsifiers and sometimes additional milk ingredients. Those added dairy components reintroduce lactose that would otherwise have been broken down during aging. Still, even at the higher end of estimates, American cheese contains far less lactose than liquid milk, yogurt, or ice cream.
Can You Eat It if You’re Lactose Intolerant?
Most people with lactose intolerance can handle American cheese without trouble. The general medical consensus is that up to 12 grams of lactose in a single sitting is tolerable for most lactose-intolerant individuals, especially when eaten alongside other foods. Even if your slice of American cheese lands at the high end of the range (around 4 grams), that’s still well under that threshold. A grilled cheese sandwich with two slices would remain comfortably within tolerance for the majority of people.
Fermented dairy products like cheese are generally better tolerated than milk for another reason beyond just lower lactose numbers. The bacterial cultures used in cheesemaking partially break down lactose during fermentation, and some of those beneficial bacteria survive in the finished product, helping your gut process whatever lactose remains.
If you’re highly sensitive and want to minimize your exposure, opt for a natural aged cheese like cheddar or Swiss instead. But for most people, a slice or two of American cheese on a burger is unlikely to cause symptoms.
How to Check Your Specific Brand
Since lactose content varies between products, the nutrition label is your best guide. Look at the “Total Sugars” line. In cheese, sugar and lactose are essentially the same thing, so if the label reads 0 grams of sugar, the lactose content is negligible. If it reads 1 or 2 grams, that’s your approximate lactose per serving.
Products labeled “pasteurized process cheese food” or “pasteurized process cheese product” (like some individually wrapped singles) tend to contain more added dairy ingredients and therefore more lactose than products simply labeled “pasteurized process cheese.” The distinction matters if you’re trying to keep your intake as low as possible. Deli-sliced American cheese from the counter is often closer to real cheese in composition and typically falls on the lower end of the lactose range.