Odds and Ends

Nutrition-wise, I have been working on a resource on zinc for the Vegetarian Nutrition Dietetic Practice Group.

The only new info from that research that I had not been considering before is that people who eat a lot of soy and who take calcium supplements might have higher zinc needs. Since I fall into both those categories, I’m wondering if that’s why I seem to benefit so much from zinc. I’m happy to report that I still have not gotten more than the mildest and shortest of colds since starting zinc supplements a number of years ago.

Many links I’ve wanted to share with readers have been building up and so I’m going to knock them all out in one post right here.

Regarding the report suggesting saturated fat intake has no bearing on heart disease (see Saturated Fats in the News), Dr. Rose Marie Robertson of the American Heart Association wrote a response worth sharing: Chief Science Officer ‘sets record straight’ about diet, science, AHA.

Examine.com is a website with a panel of health writers who research a wide array of nutrition supplements and other topics. They appear to do an excellent job of assessing the research. Along with the Linus Pauling Institute at Oregon State University and the Office of Dietary Supplements, I can see Examine.com as being one of my go-to sites for seeing what research is out there.

Speaking of go-to sites, Dr. Michael Greger of NutritionFacts.org has just released Latest in Clinical Nutrition: Volume 19.

On March 10, the Washington Post ran an article (originally appearing in NewScientist) suggesting that many species of invertebrates feel pain: Do lobsters and other invertebrates feel pain? To summarize the article: octopi, squid, lobsters, crabs, and shrimp: yes. Insects: no.

Speaking of invertebrates and pain, there is a movement among some animal protectionists to promote bivalveganism. See The Ethical Case for Eating Oysters and Mussels – Part 2 at Sentientist. The author, Diana Fleischman, argues that bivalveganism can solve many of the nutrition dilemmas posed by vegan diets such as B12, iron, omega-3s, and zinc. It does seem like a decent solution for people who find it hard to thrive on vegan diets.


Vegan and animal advocate J Tower makes some pretty cool and functional furniture out of reclaimed materials. Check out his furniture here.

17 Responses to “Odds and Ends”

  1. PEM Says:

    To your knowledge, is there a reason oysters and mussels are listed but not scallops and clams?

  2. Rhys Says:

    Some people think scallops might be able to feel pain because they have a more sophisticated nervous system than oysters and mussels. Clams, I believe, are more likely to require some sort of sea floor dredging, which could harm other animals. (Oysters and mussels can be rope or elevation raised, so no dredging is required.)

  3. Ian Says:

    Three objections to seeing bivalves as an acceptable source of nutrition stand out to me
    1. It really is not clear that these creatures are not sentient in a way that we should see as meaningful. I would accept that the likely level of sentience may be low enough that they could be chosen preferably over other sentient beings, but I would prefer to simply not go there at all – an application of the precautionary principle.
    2. The slippery slope argument. Simply of itself this is a poor argument; but its strength lies in our observation of actual human behavior. If an exception is made because certain bivalves are “not sentient enough”, then it will make it easier for some to accept that animals just a little further “up” the “sentience ladder” are also “not sentient enough” for us to worry about killing them for food, and so on.
    3. The nutritional challenges that vegans face are general in terms of to whom and where they apply. Theoretically then all vegans, irrespective of where they live, could “benefit” from eating bivalves. As with meat farming, to provide enough bivalves for the general population to eat with enough regularity to be nutritionally meaningful, would, I imagine, create large scale environmental destruction and pollution. Just as so-called humane farming – such as Salatins Polyface farm – cannot supply meat, dairy and eggs to the whole population, I don’t see that massive scale bivalve farming can be done in an ecologically sound way.
    I feel that an authentically vegan approach is to eat a healthy plant diet and use supplements as we discover them to be necessary. The main objection to supplement use that I hear is they are not natural and show a deficiency in the vegan diet. Well, growing bivalves to meet a perceived dietary lack is also an “artificial solution”, and if 99+% of my diet is whole foods, unprocessed or minimally processed, and as organic as I can afford, then that is natural enough for me. Especially as I live in a house that is insulated, heated in winter, hooked up to gas, water, electricity and the internet; I drive a car, have a smartphone and tablet, work in a hospital, access health care of the appropriate kind (hi or lo tech) as I need it; wear clothing; etc, etc…None of which is “natural”.
    The original definition of the term “vegan” from the 1940s works for me. It is true that is does allow an “out” by deferring to necessity as trumping purity, but the intent is clear: give sentience the benefit of the doubt and priority and if a “problem” can be solved without using sentient beings, then do so.

  4. Jack Norris RD Says:



    One significant problem is that there is a group of people who don’t seem to be able to thrive on a vegan diet even with supplements and so they are either going to eat mammals, birds, fish, eggs, or milk, or they could eat oysters and mussels isntead (assuming this solves their nutrition dilemma). My guess would be that if you replaced all the farming of the typical animal products with the farming of bivalves for the people who cannot be vegan, the environmental destruction of producing the totality of animal products would be a huge improvement over what it is today.

  5. Sasha Says:

    Dear Jack,

    Could you, please, elaborate or provide a link for “people who don’t seem to thrive on vegan diet”? Is it speculated why can’t they? Will they be able to thrive with some adjustment (say eco-atkins and (non-existant?) cholesterol supplement)?

    Thank you

  6. Jack Norris RD Says:


    For examples of ex-vegetarians, take a look through the posts I’ve made on this page:


    This current post that you’re commenting on is the one at the top, so you’ll need to scroll down below that one.

    > Will they be able to thrive with some adjustment (say eco-atkins and (non-existant?) cholesterol supplement)?

    That’s the question we all want an answer to. In many cases of ex-vegetarians that I’ve read on the Internet, my sense is that it was iron deficiency (in some cases it was obviously iron deficiency) or not enough protein. But I don’t think that necessarily explains all the cases.

  7. Ian Says:


    You may be right about the reduction in harm that would come from non-vegans switching to bivalves instead of land animals or fish. I was to an extent allowing the perfect to be the enemy of the good in my comment.
    I have been around so much dietary nonsense that I am more skeptical than you seem to be about people accurately assessing their “ability” to be vegan and thrive (I acknowledge that your opinion is based on way more knowledge and experience than mine is). If an “out” is offered to justify the use of animal products, I think many people will take it and allow a perceived physiological need for animal food to justify continued consumption without moral concern. However over time if veganism grows this will work itself out.
    Is it clear that some people who are otherwise healthy cannot thrive physically on a vegan diet even if they have a profound motivation and access to information and qualified help; or do you think that most of those who decide to stop a vegan diet either do not have the inner motivation to continue, have difficulty adapting in terms of preferences to new food habits, or lack good information?

    Thanks for your excellent work here.

  8. Jack Norris RD Says:


    I have noticed that very few animal activists that I know fail to thrive on a vegan diet. These people are also typically not health-motivated and so are willing to eat vegan meats or soymilk (which provide protein) and take supplements. They also tend not to be drawn to extreme diets.

    Iron deficiency can be a real problem for small percentage of vegetarians, no matter what their motivation. And there are some others who are highly motivated but still fail to thrive, although I think they are the rare exception.

    Unfortunately, I don’t have any hard data, these are merely my observations.

  9. Dan Says:

    Another possible cause of failure-to-thrive on a vegan diet is DHA deficiency, if you believe the evidence that DHA deficiency is related to depression, anxiety and other mental health issues. Vegans don’t eat fish and if they are not willing to take a DHA supplement (either microalgal or fish oil), they will likely end up with very low DHA levels.

    I do not think that protein deficiency is a limiting factor for most vegans, even whole foods based vegans. On the other hand, iron deficiency anemia, B12 deficiency, omega-3 deficiency could be real issues. We are doing a disservice to new vegans if we ignore these issues.

  10. Jack Norris RD Says:


    It’s funny that you write that about DHA since the last I knew you were leaning towards the “DHA doesn’t matter” camp.

    > I do not think that protein deficiency is a limiting factor for most vegans,

    I agree. I’m only suggesting that it plays a role in the people who fail to thrive, but most vegans are doing just fine on protein.

  11. Dan Says:


    >>since the last I knew you were leaning towards the “DHA doesn’t matter” camp.

    I was really only referring to the failure-to-thrive (ex)-vegans. There are three small randomized trials suggesting that omega-3 PUFA are effective for treating depression (appended to the end of this comment). In addition, animal experiments, though unethical, suggest that in primates deprived of DHA through several generations, that their offspring have problems with visual perception. I think it would help to at least try high-dose omega-3 in a failing vegan before giving up. I think it might make some difference to mood and well-being.

    1) http://www.ncbi.nlm.nih.gov/pubmed/?term=12888186%5Buid%5D

    2) http://www.ncbi.nlm.nih.gov/pubmed/?term=11870016%5Buid%5D

    3) http://www.ncbi.nlm.nih.gov/pubmed/?term=12365878%5Buid%5D

  12. Zachariah Says:

    Dear Jack,

    Are you aware of any established connection between zinc deficiency and recurring mouth ulcers?

    (Or indeed any other deficiency that might be more common on vegan diets.)

    I ask because, anecdotally, I know someone who gave up being a vegetarian because he kept getting recurrent and painful moth ulcers. I recently remembered his comment when I got (another!) mouth ulcer recently, and when Googling it to see what I could do about it, there were a few scattered references to either B12, iron, or zinc.

    Since you’re currently researching zinc, I thought you could shed some light on the matter.

    (PS. Keep up the great work!)

  13. Jack Norris RD Says:


    Mouth sores can be a symptom of zinc deficiency.

  14. CAW Says:

    The AHA blog post on saturated fat by Dr. Rose Marie Robertson (“Chief Science Officer ‘sets record straight’ about diet, science, AHA”) appears to have been pulled by the AHA.

    Do you know the reason?

  15. Jack Norris RD Says:


    That’s too bad. No, I don’t. I just searched the AHA site for “Robertson” and can’t find any similar article to replace it. Maybe it was causing them too much controversy to continue to respond to their critics.

  16. CAW Says:

    I’m skeptical. It seems ethically questionable to post something like that and then to quietly pull it due to criticism, leaving a 404 error.

    Take the Economist, for example, which recently posted a slavery-apologist review of a book about slavery and capitalism. The review garnered tremendous controversy and criticism; the Economist pulled the review but left an explanation and apology, along with a link to the retracted review in the interests of transparency. That’s how you pull something due to criticism.

  17. Voidspawn Says:

    The case for eating oysters is an extremely good one. First, even if we were to give the benefit of the doubt to oysters that they have a degree of sentience (extremely doubtful) — it still causes less harm to raise and eat them than the growing of land food, since it doesn’t involve accidental deaths during the harvesting process as well as deforestation and other issues. In my case, all the oysters I eat are local as well.

    Secondly, oysters just happen to fill the few gaps of a vegan diet. We can’t find b12 in plant foods, and they happen to be extremely high in absorbable B12. Zinc is harder to get on a vegan diet and as far as I know isn’t as absorbable either, which makes our daily requirements higher than non-vegans (especially as males). An oyster a day solves this issue. It’s also high in iron, which as Jack mentioned, can be a real problem for some people. For me, having IBD and having bloody stools regularly, it is a way to get more absorbable iron as well without relying on supplements.

    Lastly, I believe that eating oysters has a beneficial mental effect. I enjoy feeling like I have one of the most unique diets in the world. I am outside of the cult of veganism and dogma surrounding some of its parts as a bivalvegan. Oysters are also a delicacy, it feels special to eat one. In my experience there is no slippery slope with them; it’s not something addictive like other animal flesh foods and dairy products. It feels like I’m rewarding myself for being on a plant-based diet when I eat one a day. In the town that I live, I do not know a single person on a plant-based diet, so having a reward for not confirming to my environment feels good. As someone who relapsed in the past, I feel like this offers consistency and gives me confidence in the belief that I am giving my body everything it needs while living as ethically as I can.

Leave a Reply