I’m always curious about what causes a person to go vegan and I always ask. As an educator and an activist, I’m interested in knowing exactly what message grabbed someone’s attention and put them on the road to veganism. My own background is in public health nutrition which means that I studied both nutrition and education. I’ve also taught Nutrition Education courses to dietetics students, and spent a lot of time looking at the literature on how we craft messages to convince people to change their behavior.

But the answers remain elusive for public health experts, and are much more so for vegan advocates—given the type of lifestyle and belief change we are seeking. We don’t have any real data on what works. So I continue with my informal surveying, asking individuals what they were reading or looking at or to whom they were talking at the moment that they began thinking about veganism.

The names that come up most often are, not surprisingly, PETA and Vegan Outreach (or an individual working on behalf of those organizations). Without a doubt, the books most commonly mentioned are Diet for a New America by John Robbins and Animal Liberation by Peter Singer—especially among those who have been vegan for 20 years or so. (Despite the fact that I have many criticisms of DFANA, I have to admit that it is the book that caused me to go vegan.) People will also often say that a friend got them to look at a video from an animal rights group, and this had a big impact on them. And very recently, I’ve been promoting the book Eating Animals by Jonathan Safran Foer to friends and colleagues and have been pretty gratified by the feedback. None of that surprises me since these groups and books have powerful messages. But other responses have been unexpected.

I’ve recently been chatting with a new online friend who is on the fast track to veganism. She started out being inspired by the Meatless Monday campaign to decrease her meat intake for health reasons. Here is what she wrote to me a couple of weeks ago:

From Meatless Mondays to veganism! …What started out as an investigation into diet for health reasons has morphed into something completely different. I feel like my sensitivity sensors have been awakened from a long sleep with regards to animals. I tried to watch Meet Your Meat last night and only made it 5 minutes in before I had to stop. I am really starting to question the way human beings not only do what we want with animals because we can, but our right to use them at all for anything.”

I’ve always been critical of promoting a reduction of animal foods for health reasons, but I’m being forced to re-evaluate my position a little bit. This is not the first time that someone has told me that they started out reducing meat for health reasons and ended up as an ethical vegan. It shouldn’t really be a surprise I guess. Clearly, people are more likely to feel ready to hear an ethical vegan message when they are comfortable with vegan food or even with eating less animal food in general.

Anyone who is involved in public education knows that different types of messages reach different groups of people. In her excellent book Strategic Action for Animals (a must-read for all serious activists), psychologist Dr. Melanie Joy gives sound advice about crafting messages. But she also admits that the animal liberation movement doesn’t have the answers to some important questions about the use of different types of materials for different groups. She points to the important work being done in this area by the Humane Research Council and suggests that market research must be a priority for this movement.

Until we have that research, we have to be humble enough to know that we’re all stumbling around to some extent. We shouldn’t be dismissive of any (non-offensive) campaign or message or book just because we don’t like the way the message is presented. Nobody knows the one and only true way to promote veganism and animal liberation. And we are likely to end up being surprised by some of the things that work.