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This landmark study suggested that exposure to dietary yeast—like baker’s yeast, brewer’s yeast, nutritional yeast—may worsen the course of Crohn’s disease, an autoimmune inflammatory bowel disease. The reason they even thought to do the study was because Crohn’s patients tended to have “elevated levels” of antibodies to yeast.

But that’s not the only autoimmune disease with increased yeast antibodies. The same has been found in lupus patients, and rheumatoid arthritis, another joint disease called ankylosing spondylitis, autoimmune liver disease, and autoimmune thyroid disease. So, might avoiding yeast help those conditions, too? They haven’t been put to the test, but hidradenitis suppurativa has. What is that?

Hidradenitis suppurativa can be a pretty gruesome disease. Starts out with just like pimples, though, typically along parts of the body where there are folds—armpits, groin, buttocks, under the breast. Then, “painful…nodules form,” which turn into abscesses and drain a “thick,…foul-smelling” pus. And then, it gets even worse, forming these active tunnels of pus inside your body.

And, it’s not that rare. An estimated prevalence of like 1 to 4 percent. That’s like 1 in 50. Clothes typically cover it up; so, it remains hidden, but you can often smell the pus oozing out of people. There are all sorts of surgical options and chemotherapy, but why did they even think to try diet for the condition? I mean, you can see Crohn’s disease as a disease of intestinal inflammation, how a food you react to could make things worse; but why a disease of armpit inflammation? Because there seems to be a link between hidradenitis suppurativa and Crohn’s disease. Having one may make you five times more likely to have the other. So, there may be “an immunopathogenic link” between the two. They may share similar abnormal immune responses.

So, if cutting yeast out of Crohn’s patients’ diets helps them, then maybe cutting out yeast might help those with HS. A dozen patients with hidradenitis suppurativa were put on a diet that eliminated foods with yeast, like bread and beer, and they all got better—12 out 12. “[I]mmediate stabilization of their clinical symptoms, and the skin lesions regressed,” reversed, went away within a year on the diet.

Okay, but how do we know it was the yeast? By cutting out a food like pizza, you also may be cutting out a lot of dairy, and that’s the one other thing that appears to help. “A dairy-free diet” led to improvement in like five out of six patients.

See, these tunnels of pus are caused by the rupture of the same kind of sebaceous glands that can cause regular acne. But, in hidradenitis suppurativa, they explode, and “[d]airy products contain 3 [things] that drive the process” of clogging up your pores, and contributing to the “leakage, rupture, and ultimate explosion.”

First, there’s the casein, which elevates IGF-1 (I’ve got probably a dozen videos on that). Then, there’s the whey and lactose, and third, the hormones in the milk itself: six hormones produced by the cow, her placenta, and mammary glands that end up in the milk. So, why not try cutting out dairy, and see if things improve?

There’s a whole series of nasty drugs you can try to beat back the inflammation. But, as soon as you stop them, the disease can come roaring back. Even after extensive surgery, the disease comes back in like 25 to 50% of cases. So, we are desperate to research new treatment options.

But, patients aren’t waiting. They’re getting together in online communities, sharing their trial and error through social media, and people reported successes cutting out dairy and refined carbs, like white flour and sugar. So, this dermatologist in New Hampshire was like, okay, let’s give dairy-free a try, and 83% of his HS patients he tried it on started to get better, and he didn’t even try cutting out the sugar and flour.

Now, this wasn’t a clinical trial or anything, he just figured, why not? It’s not easy to do a randomized clinical dietary intervention, but that doesn’t stop individual patients from giving things a try. I mean, you understand why there has to be institutional review boards and stuff when they out new, risky drugs and surgeries. But if it’s just a matter of trying switching to soy milk or something, why do they have to wait? “As patients search for an effective path to [clearing this horrible disease], they need support and guidance to follow the most healthful diet available, free of dairy and highly processed sugar and flour. Nothing could be more natural.”

What about the yeast, though? How do we know it was the yeast? And look, eight of the 12 patients just went through surgery; so, maybe that was why they got so much better. It’s like when I hear someone who has cancer and goes through the conventional chemo/surgery/radiation followed by some quack clinic in Mexico, and then attributes their cure to the wheatgrass colonics or whatever they got. How do they know it wasn’t the chemo/surgery/radiation that saved them? In this study, why do we suspect it was the yeast?

Because not only did every single one of the patients get better; every single one showed “an immediate recurrence of skin lesions following accidental or voluntary consumption of beer or other foods [like bread].” So, not only did the elimination of yeast result in “rapid stabilization” and “complete, regression” of the lesions “within a year,” but, in every single case, take a little brewer’s yeast or something, and within 24 to 48 hours, BAM—symptoms are back. So, that’s why the researchers concluded that “[a] simple exclusion diet could promote the resolution of the skin lesions involved in this disabling and [perhaps actually not-so] rare disease.”

What was the response in the medical community to this remarkable landmark study? “Why was there no mention of informed consent and ethics committee approval…?” Letter after letter saying, wait a second, you violated “the Declaration of Helsinki,” which is like the Nuremburg Code or Geneva Convention to protect against involuntary human experimentation. Yet where was the institutional review board approval for this yeast-exclusion study? To which the researchers replied, look, we just told them to avoid a few foods. We gave them the choice; look, we can put you on drugs that can have side effects, cause liver problems, or you can try out this diet. And “[t]he patients preferred the diet.” Not to mention, I would add, that they were all cured!

Anyway, bottom line, by avoiding foods, like pizza, which contains both dairy and yeast, sufferers may be able to prevent their armpit from turning into this: stage three of the disease.

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