It's easy to get answers about health and nutrition! Just send your question by email to and Dr. Harlan will respond to selected questions of general interest. Answers will be posted in the Ask Dr. Gourmet newsletter (sign up now!) and archived in the Ask Dr. Gourmet section of the website.

Please note that the Ask Dr. Gourmet feature is restricted to questions regarding food and nutrition. Due to the many questions we receive, not all questions may be answered. For more specific questions about your individual health, please contact your doctor. About Timothy S. Harlan, MD, FACP | Terms of Use | Privacy Policy



Ask Dr. Gourmet

Will cooking a food affect its lactose content?

Does cooking affect lactose? For example, will baked goods made with milk be OK for someone with lactose intolerance?

Dr. Gourmet Says...

a banana nut muffin cut in half and spread with butter

No. Cooking does not affect lactose.

Lactose is a sugar that is made up of two different sugar molecules. The disaccharide (di for two and saccharide for sugar) is made up of the two sugar molecules, galactose and glucose. The bond that holds these two sugars together is broken by an enzyme called lactase. The reason that many folks are lactose intolerant is because their bodies don't make the enzyme lactase.

Cooking or baking will not break the bond.

Keep in mind that lactose intolerance can be dependent on the amount that you eat. For instance, some people can tolerate the small amount of milk in baked goods or even a as much as a half a cup of milk over cereal. Because of the small amount in baked goods like muffins, this may be something you can tolerate. (For example, in my Banana Nut Muffins recipe there's about 1 teaspoon of buttermilk in each muffin.)

Timothy S. Harlan, MD, FACP
Dr. Gourmet