Realistic Demands on Nutritional Medicine
While writing this article, I couldn’t quite make up my mind:
- Rant?
- Sequel to another article?
- A description of my motivation for running this site?
It became a bit of everything.
The occasion was an episode of the Abendblatt podcast with Dr. Matthias Riedl, the “poster boy” of German nutritional medicine and TV doctor, who has already been the subject of several pieces here, in which I mostly took a position opposite to his.
In a new episode - this time not with the NDR Ernährungsdocs directly, but with the Hamburger Abendblatt(1) (embedded here as a YouTube video) - he talks about the biggest misconceptions in nutritional medicine - and he actually has a point.
Where do we start?
My Motivation
On butterbei.de I report on experiences with a diet that deviates far from the standard of the DGE . That may be the ketogenic diet, or even its fibre-free variant. My goal is the informed patient: all too often, the nutritional guidelines are presented as the be-all and end-all of nutrition, the gold standard, and every diet that deviates from them as deficient or actively harmful - even though that is far from true for many of them.
Instead - even within the official recommendations - fear is stoked around the very foods with the highest nutrient density. And that although the underlying studies are of dubious quality and, in particular, cannot demonstrate cause and effect.
But let’s get back to Dr. Riedl, and to my current reason for putting him on the agenda yet again:
Unrealistic Expectations
Anyone who remembers his earlier demand for studies to pharmaceutical approval standards for a ketogenic diet will be surprised that he apparently doesn’t mean it that way after all. Or won’t be surprised at all, because even back then he didn’t look too closely at things that fit his world view. That was my main problem with his statement at the time: the application of a double standard.
When different standards apply...
Two Yardsticks
When I took on his double standard back in August 2026, I criticised him for making excessive demands on the one hand while interpreting very leniently on the other - at the same time, towards different aspects.
Realistic Expectations
In this new episode, though, he goes into more detail about what kind of research can be expected in nutritional medicine, and how much case studies and experiential knowledge actually have to be taken into account.
I’m mainly referring to this part of the episode, which is in German (the embedded video starts at 21:21, but can of course be rewound to the beginning of the episode):
M. Riedl: An entire medical establishment turns against nutritional medicine, questioning it critically or rejecting it, and says: “It’s not at all the way you imagine it.” But we see people with psoriasis, eczema, diabetes and rheumatism who get better or are cured. Because that doesn’t exist in the world of experience of our traditional medicine, they are extremely critical and say: “Well, do you have a study?” Well, at the beginning you don’t have that many studies, and unfortunately such a methodological fetishism prevails that the opponents of nutritional medicine say: “As long as you can’t prove it to me in a large study, I won’t believe a word.” That is methodological fetishism, and it gets us nowhere. When a discipline is emerging, we have experience, we have smaller studies, we have a body of evidence that keeps getting denser, but that isn’t yet the placebo-controlled randomised trial - which is difficult with food anyway. Who’s going to pay for it?
Aha! So the technical term for one of the “two yardsticks"(2) is “methodological fetishism” ☝️🤓💡 - I’ll remember that for future episodes.
That is exactly the point where I don’t know where I stand with him: I agree 100%. If only he would also apply this principle in areas where oats would be limited on the menu, or eliminated(3).
The ketogenic diet now offers so many case studies documenting remission or massive improvement in many non-communicable diseases of civilisation that it can no longer be ignored. Unfortunately - as criticised several times in other articles - it often isn’t even offered as an option. Instead, Dr. Riedl, as discussed back then and now justified in his own words, has set unfulfillable demands before the ketogenic diet may even be considered.
For these statements about diseases of civilisation, you don’t even need to rely on a nutrition nerd. Dr. Riedl himself says what diet can achieve here:
No Promises of a Cure, but…
M. Riedl: All diseases of civilisation can be improved by nutritional therapy, many of them can be cured, and sometimes you also relieve the impairments to well-being along the way. There’s no promise of a cure - you’re not even allowed to make one. But we do have outstanding examples…
Of course I can’t promise a cure either - I couldn’t even if I were a certified nutritional physician myself. My concern is this: patients should know the options that have already succeeded in so many cases where medicine is merely managing symptoms - all the more so because, for the reasons Dr. Riedl gave, there are no large randomised placebo-controlled trials for them. They can then decide for themselves what they consider the greater sacrifice: giving up bread and grains (on a ketogenic diet), or giving up their own foot(4).
Anyone happy to part with the foot, or who doesn’t have diabetes, may find the symptoms of bipolar disorder(5), Crohn’s disease(6) or multiple sclerosis(7) better candidates for giving up (this list is far from complete).
That a ketogenic diet doesn’t even contradict the DGE’s recommendations in any of these cases, because the guidelines explicitly apply only to healthy people, is something we’ve already covered.
Who are the DGE recommendations for?
DGE Guidelines. A Contradiction?
Why the recommendations of the German Nutrition Society don’t actually contradict my completely different personal experience
Read more →Calorie Counting
I can’t close without one more quote:
A little before the start position linked above, at 20:47, we hear:
M. Riedl: The worst diet is simply calorie counting - but we’ll have to do a separate podcast on that.
Here, too, we agree completely - but I suspect the agreement only goes skin deep. I’m curious to see this plan put into practice and will probably comment again. In the meantime, several aspects of the calorie balance and alternative - better fitting - mental models are on my list of topics.
An alternative view of the calorie balance
Caloric Balance: Cause or Effect?
An invitation to reverse the causality: why explaining weight loss through reduced calorie intake is not very helpful
Read more →For now, though, I note: strictly speaking, there is nothing to criticise this time in the concrete statements made in this podcast - we just draw different conclusions from them, argue from a different realm of experience, and trust people to have different amounts of self-motivation and perseverance.