The Differences Between Lactose-Free and Dairy-Free

Dairy-free is lactose-free, but not vice versa

Man shopping for milk
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You will often see the terms lactose-free and dairy-free on various products and foods. But do they mean the same thing? Actually, no. Lactose-free foods are dairy products where the lactose has been removed, whereas dairy-free means there is no dairy at all—the food is made from plants or nuts instead.

Understanding these labels is important for people with a milk allergy (also referred to as dairy allergy).

Lactose-free products are made for people with lactose intolerance but they are usually not suitable for people who have milk allergies or who are on a vegan or dairy-free diet

Lactose Intolerance

Lactose is a sugar found in milk and milk products. Our bodies produce an enzyme called lactase, which helps us to digest lactose properly. In some people, the body stops producing adequate amounts of lactase and they become unable to digest the sugar properly, causing gastric discomforts such as gas, bloating, cramps, diarrhea, and nausea.

For some, ingesting small amounts of foods containing lactose may not cause any problems, or those who are lactose intolerant may find that they can eat yogurt and goat's milk. There are also lactase tablets which help in digesting lactose. But for people who cannot tolerate lactose, choosing lactose-free products is their best bet.

Lactose-Free Foods

Since lactose is found only in milk, only products that contain milk can be lactose-free.

Therefore, dairy products containing milk are the only types of dairy that can be lactose-free. So that means cream, buttermilk, some cheeses, ice cream, sour cream, and even hot chocolate mixes are forbidden to those who are lactose intolerant. Luckily, there are lactose-free versions of many of these foods out there on the store shelves.

Just look for the "lactose-free" on the label.  

Milk Allergy (A.K.A. Dairy Allergy)

Milk allergies are the most common food allergy in infants and young children. A person with a milk allergy is often allergic to one of two protein components of milk: ​casein and whey. The body's immune system overreacts to these specific proteins, causing mild symptoms such as hives, itching, and swelling, to more serious symptoms like wheezing, trouble breathing, and even loss of consciousness. Therefore, those with a milk allergy should not ingest any food that contains milk. 

Dairy-Free Products

To understand the dairy-free label it is best to understand what dairy actually means. Dairy refers to milk and any part of milk that comes from cows and other mammals. Thus, to be dairy-free, a product must have no milk and no ingredients that are part of milk.

Since lactose comes from milk, a product that is dairy-free will not have lactose in it. This means that a product which is dairy-free is also lactose-free—but remember that a product that is lactose-free is not necessarily dairy-free.

Dairy-free products do not contain casein and whey, but these proteins are often found in products labeled lactose-free since removing lactose from milk products may not eliminate these proteins.

These proteins will still be present unless there are other forms of processing done to remove them.

Choosing Between Lactose- and Dairy-Free

In order to choose the best eating plan, you need to know if it is a lactose intolerance or a milk allergy. If you or your child are allergic to dairy or parts of milk like casein or whey, then steer clear from lactose-free products and stick to those that are labeled dairy-free or vegan. It is important that you become familiar with dairy-derived ingredients so you know which products are safe for you and your loved ones. If you or your dependent have been diagnosed with lactose intolerance, then simply look for the lactose-free label.

Another thing to keep in mind is that there are also differences between the terms dairy-free and non-dairy. Dairy-free is not a term regulated by the U.S. Food and Drug Administration—it is an industry and marketing term.

Non-dairy is the regulated term and it actually allows for the presence of milk protein such as casein, whey, and other derivatives. If you have a milk allergy, non-dairy products may not be safe. 

If you are following a vegan diet, you will not consume any dairy products—whether or not they are labeled as lactose-free—since dairy products come from animals. Therefore labels that read "dairy-free" may be safe for those eating vegan as long as there are no other animal products in the ingredient list.