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Stanford study spoils hopes that raw milk can aid those who are lactose-intolerant

Stanford study spoils hopes that raw milk can aid those who are lactose-intolerant

milk in fridge

I have a few friends who can tell pretty quickly when they’ve eaten a food that contains milk or lactose, the sugar found in milk. The signs are unpleasant — mostly gas and diarrhea (yuck!). So they were interested when I told them that a nutrition researcher at Stanford was conducting a clinical trial to test the validity of claims that people who are lactose-intolerant can digest raw milk more easily than pasteurized milk.

Unfortunately for them, the claims don’t hold up.

In my news release about the study, which was published today in the Annals of Family Medicine, professor of medicine Christopher Gardner, PhD, found no difference in digestibility between the two.

Although the study was small — just 16 participants who were lactose-intolerant — the results were highly consistent among all the participants. As Gardner notes in the press release, “It’s not that there was a trend toward a benefit from raw milk and our study wasn’t big enough to capture it; it’s that there was no hint of any benefit.”

One thing that surprised Gardner was how many people believe they are lactose-intolerant because of the symptoms they experience, yet don’t meet the clinical standard for the condition. In fact, Gardner originally recruited 63 potential study participants, but only 43 percent of them actually met the standard.

So, what’s causing the discomfort that this group of people feel when they consume milk products? And would raw milk — which hasn’t been pasteurized and which proponents say contains “good” bacteria that may aid digestion — help folks who don’t meet the clinical definition of being lactose-intolerant? Gardner says he hopes other researchers will try to answer those questions.

Previously: Stanford pediatrician and others urge people to shun raw milk and products
Photograph by chrisdat

2 Responses to “ Stanford study spoils hopes that raw milk can aid those who are lactose-intolerant ”

  1. Gordon S Watson Says:

    this article is seriously lacking ; it does not explain what’s necessary for a formal diagnosis of “lactose intolerance”. If such a ridiculously-small sampling were done by proponents of REAL MILK, ie raw milk, it would be invalidated as “anecdotal”. The hundreds of people in our raw milk cowshare, pay $20 per gallon for the good stuff = whole, fresh pure, non-homogenized milk, UN-cooked, from grass-fed cows = because we know something this scientist cannot figure out

  2. August Pamplona Says:

    Gordon, this article references a press release by the same author. There’s more information in that press release and it appears to be a relatively complete description. What a formal diagnosis is is explained there and it seems like a reasonable diagnostic standard.

    It doesn’t look like study is that horrible. As far as pilot studies go (which is all this is), it might even be good although there seem to be issues with the blinding (it’s basically blind and a half because even if the researchers did not know what kind of milk they were handling, the participants got better at figuring out what they were drinking in later phases of the study). However, I would guess that poor blinding of participants would tend to reinforce their pre-existing beliefs not counter them.

    The actual study can be found at

    P.S. The fact that some people may be foolish enough to be willing to pay a lot money for something does not *necessarily* mean anything beyond the fact that they are willing to pay a lot of money for something. This is proven time and time again every time someone purchases a Monster brand cable…. Or maybe every time someone purchases a Monster cable an angel loses their wings…. I always get confused about which is which.


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