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In addition, my old website, Planet Lactose, has been taken down because of the age of the information. Unfortunately, that means links to the site on this blog will no longer work.

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Saturday, April 03, 2010

Report from the LI Conference, part 19

This presentation and the next one are going to infuriate everyone. They're so connected that I'm going to vary from the way I've been handling these posts and put the two of them together.

Dosing, Symptoms, and Tolerable Doses of Lactose
Dennis A. Savaiano, Ph.D.
Professor and Dean
College of Consumer and Family Sciences
Department of Foods and Nutrition
Purdue University

Evidence-based Practice Center Presentation III: The Tolerable Amount of Lactose Intake in Subjects With Lactose Intolerance
Michael Levitt, M.D.
Minneapolis Veterans Affairs Medical Center
Division of Gastroenterology
Department of Medicine
University of Minnesota

The titles sound innocuous enough. If you click over and read the summaries of the presentations, you'll see that in broad generalities they say very little that I haven't said before and haven't repeated what feels like a dozen times just in my reports on the NIH Conference.

Believe me, the talks that they gave weren't so bland. I'll put it into a sentence.

Nobody gets symptoms from lactose.

Ridiculous, right? Ludicrous even. This whole blog is about lactose intolerance. My books are about LI. The conference was the state-of-the-science on LI. I've received thousand of letters and emails and posts from people telling me about their LI symptoms. Both presenters are researchers who've spent entire careers writing about LI.

Something's totally nuts here. I wish I knew what.

Figures 1 and 2 from Levitt's presentation won't reproduce well here so you have to click over and look at them. They represent the findings from a series of major studies on lactose. A minus sign means that a certain dose of lactose - with other foods in Figure 1, by itself in Figure 2 - produced "no or trivial symptoms" in the test subjects. "Severe symptoms" - the kind I think I get and the kind you tell me you get - are represented by a double plus sign. Remember that an eight-ounce glass of milk has about 12 grams of lactose in it.

When you look at the charts you'll see minus signs for all doses up to and including 12 grams. Virtually no one in the entire set of experiments got symptoms from the lactose in a glass of milk. If you used milk itself or some equivalent, a dose closer to what happens in the real world when you have dairy, no one, not a soul, got symptoms from two full glasses of milk.

Their breath hydrogen goes up, the certain signal that they are lactase maldigesters. But no symptoms.

Savaiano talked about experiments in which subjects received 50 grams of lactose over the course of a day without a single one of them having any symptoms.

Look, as I've reported earlier, the testing in the medical literature is bad. The groups are small, the experiments are not blinded, the doses are not physiologic, meaning that they don't correspond to the foods or eating experiences you get in everyday life. Still. Nothing? No symptoms? Sure, forcing a test subject to drink a full 50 grams of lactose in water - at one time the standard amount of lactose used in testing - will make people sick. But that's like testing for drunkenness by forcing a jug of moonshine down your craw in a single gulp. Anybody would be affected by that. It's so bad a test that doctors stopped recommending its use decades ago.

I didn't get it then, and I don't get it today. I'm reporting what the medical journal evidence says. In the next part I'll give the summary from the draft report. But I'll put the concluding paragraph here.

We stress the importance of additional scientific investigations to provide evidence-based and culturally sensitive recommendations about the amount of daily lactose intake that can be tolerated by lactose-intolerant individuals, with special emphasis on pediatric and adolescent populations and pregnant and lactating women.

That's the biggest "we don't understand what the hell's going on, give us some funding money" you'll ever see in scientific language.

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