it’s a mix for me too, and has shifted and evolved over the years, and i often have the same thought when people ask——- since all reasons can’t be given and explained in a short conversation, it’s a choice of which one (or ones) to mention and get into in that moment. for myself, but also for when there are others there that have heard about it from me before, I like to use fresh info and examples.
lately, i sometimes talk about the US meat industry – not wanting to put antibiotics, steroids, artificial hormones, and (if I’m feeling thorough) the toxic elements produced by the fear and suffering of the animals into my body….. usually people understand that (and thus stop talking about it) pretty quickly—- it’s pretty hard to argue for excess antibiotics, hormones, and steroids!!
another focus could be all the other forms of protein you eat (from nuts, beans, veggies) and all the health benefits of the vitamins, fiber, etc that you’re eating. a purely positive approach, which is especially useful if you’re trying not to offend someone. they’ll just be impressed at how healthfully you eat. —hardly anyone doesn’t want to be healthier (eat less fiber, have less disease, etc).
because i’ve lived in several countries and traveled quite a bit, sometimes i start talking about different ways food, eating, and animal treatment are approached in different countries, and across different social classes, urban/rural, etc. people are often intrigued and surprised by this information, especially if they haven’t experienced other cultural perspectives themselves—- in that way, that also is an approach that can move you along to another conversation topic quickly. similarly, you can talk about historical changes in diet (comparing the quantity/quality of meat people ate 100 or 500 years ago to today) or specifically your family’s eating traditions (again, hard for someone to argue against you about what your grandmother grew up eating).
over the holidays, a veggie friend (and well-educated nurse) told me that the US is the biggest over-eater of protein, specifically animal protein. facts and statistics are a great method, and I recycle and use new ones of those (whatever is striking me most in that moment) so that I keep the conversation interesting for myself. I get new ones from movies and books (like Super Size Me, Fast Food Nation, plenty of vegan/vegetarian books and cookbooks) or news articles or websites about nutrition, obesity and cancer and depression and other food-related health issues, animal rights and farms, etc etc.