As usual with his talks, this one is full of holes. As one example, take this short clip from the presentation
The usual response to this is to talk about the research that suggests that ethical vegans tend to remain vegan in greater numbers than health vegans, for example.
Since Leenaert has for several years attacked and mocked the philosophy of veganism, preferring to tell his audiences that veganism is simply "about food," he adds this: "And it's really not so, by the way, that it's only the people who are vegan for health reasons that drop off, it's also people who are vegan for animal rights reasons that drop off."
Leenaert concludes that "compassion costs too much."
Leenaert's statement is technically correct - but deceptively so. Of course a number of people who regard themselves as ethical vegans will return to consuming animal produce. However, research suggests that only a small percentage of ethical vegans fall off Leenaert's wagon compared to those who "go vegan" for non-ethical reasons.
Let's clear up one potential source of confusion right now. It is often claimed that it does not matter why a person begins to live vegan. A health vegan is going to run into the ethical arguments sooner or later, therefore the hope is that an ethical commitment to veganism may arise in anyone interested in veganism for any reason.
This would be unimportant to Leenaert since he mocks ethical vegans. However, it turns out to be vitally important because research does suggest that ethical vegans remain vegan in far greater numbers than other groups with other motivations. While I agree that the initial motivation may not be a major concern, it is worrying if people do not move towards - and quite quickly - an ethical stance on human relations with other sentient beings - or in other words, develop "animal rights" sentiments.
In 2012, Haverstock and Forgays  looked at those they describe as "current and former animal product limiters." These authors found that their research backs up previous studies from the 1990s and early 2000s, that for "current [animal product] limiters," ethical reasons are often stated as a motivating factor and to the extent that veganism, and even vegetarianism, becomes seen as a strong element in a person's self identity. Once these elements are in place, it seems that returning to eating other animals would require them to redefine their identities. Interestingly, the importance of shifts in self identity was found to be important to health vegans as well as ethical vegans.
I think Tom Regan  was getting at a similar idea when he talked about being "a Muddler." Muddlers are people who keep adding to their knowledge, they keep moving forward, "to keep growing against the grain of our cultural paradigm concerning animals."
Regan says that suddenly, surprisingly, a Muddler will look in the mirror and see an animal rights advocate looking back.
In 2015, Ginny Messina wrote a blog entry entitled, "Preventing Ex-Vegans: The Power of Ethics."  She writes,
As I’ve been delving into this issue of preventing recidivism, I’ve looked at quite a bit of data including:
- Surveys of ex-vegetarians (from Faunalytics, the Toronto Vegetarian Association, and psychologists Childers and Herzog)
- Research on successful dietary behavior change in general 
- Research on dietary behavior of current and former vegans and vegetarians
Her conclusion upon assessing this material is impressively clear: "Vegan advocacy: put ethics first."
One of the studies she looked at, from 1997, again underlines the importance of moral values becoming internalised so that they become a part of the persons concerned. As a sociologist, I find this to be very important. A core concept in sociology is the process of socialisation, and part of that is the notion of internalisation - the "taking in" of ideas and values as a constituent part of the self. I briefly talked about that in this video.
One thing Messina found was that health vegans may stop being dietary vegans for the ironic reason that their diets may not as good as the diets of ethical vegans! How so? Ethical vegans may "enjoy a relaxed approach to food choices," making it easier for them to meet their nutritional needs. In addition, "health-motivated vegans may be less likely to take appropriate supplements."
It's not looking good for ethics-hating Leenaert, is it?
Messina points to another issue for health vegans. It is very likely that the addition of a little animal produce in their diets will not negatively effect their health. She says that a plant-based diet with a small amount of animal produce may be on par, health-wise, with a 100% plant-based diet.
So, we're back to ethics, and Messina writes
- But the ethics of veganism? Once you embrace them, there is no alternative way of living and eating. This seems to be particularly true for those who embrace an animal rights ethic.
Yes, indeed, once one of Regan's Muddlers see that animal rights advocate in the mirror, then Messina states: "If you agree that animals are not here for us to use under any circumstances, veganism is really your only option."
Ginny Messina says that she has no choice but to promote vegan diets for ethical reasons, concluding, "it appears that ethics is a more powerful long-term motivator for vegan and vegetarian diets."
Let's hope that "The Vegan Strategist" will cease distorting issues about veganism for his own ends.
 Haverstock, Katie, and D.K. Forgays (2012) "To eat or not to eat. A comparison of current and former animal product limiters." Appetite, Vol 58: 1030-1036.
 Regan, Tom. (2004) Empty Cages: Meeting the Challenge of Animal Rights. Lanham: Rowman & Littlefield.
 Messina, Ginny (2015) "Preventing Ex-Vegans: The Power of Ethics." The Vegan RD, 30 June.
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