Whether animals suffer to make animal products isn't really up for debate, only whether people care that these animals suffer for their choices. Many people don't. That animals are killed without us being aware is very different from purposefully raising and killing them.

There is nothing in animal products that satisfies nutritional needs that aren't easily found elsewhere. Usually, the "health benefits" of animal products are based on them having better, more natural diets than us. So, fish aren't born with omega-3s in them, they actually get them by eating seaweed and other plants. So, fish are healthy because they eat healthy, so eating fish to be healthy neglects that you could just eat plant products with omega 3's in them for the same benefit, etc.

Eating animal products is also directly linked to cancer promotion. There's a whole book about this, but you can get the basics at http://thechinastudy.com/ Essentially a person with cancer given milk grows cancer cells whereas soy and non-animal proteins do not grow cancer cells.

As for environmentalism, animal agriculture has been worse for greenhouse gas emissions than all of the cars on the roads, mainly because of what it takes to grow animals abnormally fast on unnatural diets for the cheapest cost possible.

So, I came to veganism entirely through intellect not morality. I'm not really into animal rights, although I certainly respect people who are. Like most things I create my own awkward path, but of the three planks, I rank them as health, environment, animal rights.

Like, I don't care about the happy life of a turkey, or whether it is being killed unnecessarily. But personally, I do not want my life to be sustained on a foundation of suffering. I have no specific love of turkeys or anything, I don't want to go to animal sanctuaries and bond with the animals like many vegans. So, it's more abstract.

When I told swimmerguy that if he was pursuing this path because of animal rights, many people don't realize that the chickens for eggs and the cows for milk live the worst lives of the entire bunch, yet a lot of people rationalize them as being OK because the animals aren't killed. Personally, I'd rather be dead than have their life. Not to mention, as soon as their milk or egg production slows down, guess what? They're killed for their meat, heh. So, prolonged agony and suffering and then they still become burgers and McNuggets at the end of it all.

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"Why be given a body if you have to keep it locked up in a case like a rare, rare fiddle?" - Katherine Mansfield