The good bugs: Acidophilus Redux

Dear Home Ec 101:

Why is it lactose intolerant people can eat yogurt but not drink milk?

Gassy in Gettysburg

Heather says:

Lactose is a sugar present in milk. To digest this, humans must have the enzyme lactase present in their system. People who are lactose intolerant can generally consume some lactose, the problem lies in the amount they can tolerate. Many adults are intolerant to some degree.

Without lactase, the sugars ferment in the gut creating gas and other unpleasant symptoms. Thankfully, lactose intolerance is uncomfortable rather than dangerous. Lactic acid bacteria live in your digestive tract and thrive on lactose. Some people have higher levels of this bactera than others. Those with high levels of these good bacteria typically do not report symptoms of lactose intolerance.

Yogurt contains L. acidophilus, a lactic acid bacteria. Not only does the bacteria present in the yogurt reduce the amount of lactose present in the dairy product itself, it adds to the population of good bacteria in an individual’s digestive tract. Now, the second benefit is only possible if the yogurt contains live cultures. Dead cultures would do nothing more than pass on through.


  1. Patia on June 20, 2007 at 3:51 pm

    Interesting! That is good to know.

    Here’s another little lactose tidbit people may find useful: Most cheeses have little, if any, lactose, because the whey is separated out in the cheese (curd) making process. Generally, the harder the cheese, the less lactose. The best way to tell is to look at the label: If the cheese doesn’t have any carbohydrates, then it doesn’t have any milk sugar (lactose)!

    Similarly, whey — often found in baked and convenience foods — is a concentrated form of lactose. (Or as I like to call it, a gut bomb.)

  2. Angela on June 19, 2007 at 9:27 am

    Most bacteris will not die from freezing, they will just become dormant until warmed again, either by air or once it enters the body. It would be if the yogurt needs to be heated before becoming frozen yogurt or yogurt for that matter. Heat=death…cold=dormant

  3. JRae on June 17, 2007 at 2:34 am

    Hey, you did your research!!

    So both camps were kinda right. If all the bacteria were killed off from freezing when making frozen yogurt, lactose-intolerant people could still eat it in relative comfort since most of the lactose has been digested already, but wouldn’t get the added benefit of adding some live cultures to their gut.

    Cool, good to know! 🙂