#340: Ethics of Veganism & Omnivorism (Part 4) – Diana Rodgers, RD & Robb Wolf

In Podcasts by Danny Lennon12 Comments

Guest Information

Diana Rodgers and Robb Wolf are the co-authors of Sacred Cow, a book exploring the important role of animals in our food system.

Diana Rodgers, RD

Diana is a Registered Dietitian living on a working organic farm in New England, where she runs an active nutrition practice. She speaks at universities and conferences internationally about nutrition and sustainability, social justice, animal welfare and food policy issues. She’s just completed work on the new book and film project, Sacred Cow


Robb Wolf

Robb Wolf is a former research biochemist and a New York Times/WSJ Best Selling author (for both The Paleo Solution and Wired To Eat). Robb has functioned as a review editor for the Journal of Nutrition and Metabolism (Biomed Central) and as a consultant for the Naval Special Warfare Resiliency program.

In this episode we discuss:

  • The benefits of regenerative farming
  • Is regenerative farming scalable?
  • The principle of least harm
  • Ethics of plant & animal food production
  • Connection between ethics, economics, politics and population health

Links & Resources

Previous Episodes in this Series

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  1. I usually really enjoy the podcast but was so disappointed listening to episode #340. As a registered dietitian I would completely dispute Diana Rodgers dismissal of the healthfulness of a vegan diet. Both the British and American Dietetic Associations maintain the position that a well managed vegan diet can be entirely adequate and healthy across the lifespan.
    Much of the rest of the claims made in the podcast conflict with everything I have read about animal agriculture systems and I suspect there were many half truths. Very disappointed to hear this pair given free rein with their claims being unchallenged.
    Perhaps you could do another episode with someone such as George Monbiot, who they were so dismissive of, to give some balance.

    1. Author

      Hi Helen,

      On the issue of vegan diets and health, we here at Sigma (myself and Alan Flanagan) have an episode upcoming about the nutritional science specifically. Whilst I agree with you that a well-formulated vegan diet can be used to be healthy (which is the premise this whole series is based on), I do have some reservations about the ADA position stand paper you mention, specifially related to the evidence they site for babies/toddlers/young children. But that will be addressed in a future episode. Overall, I have been working on the presmise that it’s very possible to be healthy on a vegan diet.

      From memory, I believe Diana said a vegan diet wasn’t the “optimal diet”, which I don’t think is controversial, given that no dietetics organization currently claims it is better than an omnivorous diet. Although perhaps I’m picking that point up incorrectly.

      As my level of animal agriculture systems is only as deep as my research for these episodes allowed (i.e. it’s well beyond my area of expertise), I’m unsure if I was able to formally challenge points beyond the questions I was able to ask.

      In my previous episodes with Hannah Ritchie, Andrew Chignell, Alex O’ Connor and Paul Thompson, they presented counterpoints, which I actually asked Robb and Diana about in this episode. I can only go on what I learned in those conversations, rather than having a really deep understanding of the research in this area.

      As for providing balance, ironically that was the point of this episode. In those previous episodes above, conclusions about both environmental sustainability and ethics both were in the direction of favouring plant-based diets, as is the 5th segment in this series. So in the series of 5 episodes, this one was the only one with points that run counter to veganism being the most ethical position. So if anything the balance is already largely skewed against the position within this episode.

      Thanks for listening to the podcast, for the kind words about it overall, and for the feedback on this episode. I’m sorry you were disappointed by this episode, but hopefully you can understand the goal of this series and episode from my position; as outlined at the outset of the series it was to listen to perspectives that I wasn’t an expert in, and try to work out where people are coming from. With the result hopefully being useful to listeners.

    2. 100% agree, considering both of them have made and continue to make many questionable claims. I do commend Danny for his respectful response and was open to hear both sides share their views, I am always going to continue and support Sigma Nutrition podcast no matter what as it is a really useful educational tool. It didn’t take long at all to identify the obvious positions of Diana and Robb, their blogs and social media platforms are very anti-vegan. It is also worth mentioning that Sacred Cow, their film that they mentioned in the episode, features many questionable ‘experts’ on the official website.

  2. Let’s listen to George Mobiot conforming this episode on sustainability, the biggest energy source on earth is cellulose, only herbivores can make cellulose into fat and carbohydrates:


    Regenerative agriculture improves soil health, peer reviewed papers:


    Organic foods improves soil health, annuals decreases soil health and increases topsoil loss:


    Grasslands are between 20% and 40% of land on earth and the most fertile soils are around cities which eats it in expasion:


    Grazing brings back birds, while pesticides decreases birds bodyweight:


    1. You should probably be aware George Monbiot wrote another article after the one you linked discussing why he was wrong again, and turned back towards cutting out animal products. (I love George Monbiot’s ability to admit when he has been wrong in the past and learn and move forward btw. Makes him far more trustworthy in my opinion than people trying to sell one narrative).



  3. In the recent WRI report and webinar on Regenerative Ag. and grazing it has become clear that they limited their research to biomass shifting thus determining limited climate benefits. Had they also included liquid/root exudate carbon production and resulting microbial necromass carbon the benefits would drastically change. The anti-regenerative and livestock grazing is primarily being driven by global investor profit potentials of a global plant-based processed food manufacturing system.

  4. Hello

    I have just discovered your podcast. I’ve long looked for an objective podcast that tries to follow the science and doesn’t favour a particular diet. I think I have finally found one! Thank you creating it.

    I’m currently listening to the series on the ethics of being a vegan or omnivore. What has happened to the 5th episode (#341) in the series. It’s not available in my podcast feed or on the website.


    1. Author

      Thanks Praful!

      The interviewee in that episode requested I remove the interview after listening back to it, as they were not satisfied with how it came across. So out of respect and courtesy, I took it down.

  5. Thanks Danny for replying – that’s fair enough!

    By the way, is there a way of receiving an email when someone comments on a thread or replies to your comment? Otherwise you have to keep checking back!

  6. This was a quack asylum episode, but for ecology. The other episodes in the series have been great, especially your episode on the nutrition science of vegan diets, which is a great service to vegan listeners. Thanks for your hard work.

    1. Author

      Thanks for the kind words Nick, much appreciated. As you can likely tell, my background is purely in nutrition science. And so topics across this series, from ethics to sustainability, are ones where don’t have expertise. The downside of this, is an inability to push back on points in real time.

      I appreciate you listening in, and for kindly saying thank you.

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