What About Lactose?
Many lactose-intolerant people assume they will have trouble digesting cheese, and because of this they avoid cheese as much as they avoid other milk products. Certainly some people with difficulty digesting milk also have difficulty digesting cheese. However, this is not always the fault of lactose.
Lactose, Lactase, and Lactic Acid
The Oxford Companion to Food defines lactose as “the main and almost the sole sugar in milk…composed of the simple sugars dextrose and galactose.” The Oxford Companion goes on to describe how lactose is digested: “Splitting lactose into these two sugars is the first stage in digesting it, and is done with the aid of the enzyme lactase.” Therefore:
Lactase is an enzyme that occurs naturally in the intestines of mammals (including people), and is also a byproduct of some yeast.
Lactic acid is what lactose becomes as it ferments. The fermentation occurs naturally in milk and is caused by milk.
Raw milk contains enough natural milk bacteria to produce lactic acid; however the rate of lactic acid production can be unpredictable. Pasteurized milk does not contain these milk bacteria. As a result, most cheese makers rely on starter cultures that contain the necessary bacteria to begin the production of lactic acid in a controlled setting. After most of the lactose has been converted to lactic acid, the process of separating curds from whey begins, and most of the lactic acid remains with the whey.
Lactase, the enzyme that digests lactose, is something your body can produce naturally, and is not a part of cheese. However, not everyone produces lactase. It is generally believed that over several thousand years, people living in areas dependent on milk and cheese (northern, central, and southern Europe; parts of Africa; most of the Americas; Australia and New Zealand) retained or developed the genetic coding needed to produce lactase throughout their lives.
In other parts of the world, such as in Asian countries, this genetic coding was not as necessary because few people drank milk or ate milk products beyond infancy. This is not to say that people from Asian countries cannot digest milk or that all people from milk-drinking countries can digest milk. It is simply a way of illustrating the fact that people's bodies have developed tolerances for milk digestion that seems to follow thousand-year patterns of milk consumption.
So, your ability to produce enough lactase to digest milk is partly dependent on your genetic coding, which may also be related to the countries of your ancestors.
Now for the really good news for the lactose intolerant. All that lactose in milk? Most of it has been converted into lactic acid or drained away with the sugar and water (the whey), and doesn't make its way into cheese! In fact, unless you're talking about a whey-based fresh cheese, like ricotta, about 95 percent of the lactose is gone, and many people who have experienced intolerance to lactose find they can easily digest cheese.
Lactose in Different Milks
Some people find they can digest goat's milk more easily than cow's milk and believe this has to do with the amount of lactose contained in each. The difference, however, is slight. One cup of cow's milk contains approximately 11 grams of lactose, and 1 cup of goat's milk contains about 9 grams. When made into cheese these differences are so slight as to be immeasurable.
Do people digest cow's, goat's, or sheep's milk differently?
There is no evidence to suggest one animal's milk is easier to digest than another's, but as with any food, different people will tolerate some foods better than others. If you've had any discomfort after eating cheese from one animal's milk, try another type and see what happens.
What to Do
Lactose intolerance has garnered a lot of media attention, and an entire folklore has grown up around the term. When people experience bloating, discomfort, or gas after drinking milk or eating cheese, they are tempted to blame it on being either partially or fully lactose intolerant.
Lactose intolerance is a real condition. But if you haven't been diagnosed with it and simply suspect you are lactose intolerant, talk to your doctor about it first and see if the condition is truly diagnosable. Or, if the symptoms you've experienced are not severe, think about trying small amounts of cheese to see if you are able to digest them. You may be pleasantly surprised.