, poultry
, and seafood
). Abstention from by-product
s of animal slaughter
, such as animal-derived rennet
and gelatin
, may also be practiced.
Vegetarianism can be adopted for different reasons: In addition to ethical reasons
, motivations for vegetarianism include health, religious
, political, environmental
, cultural, aesthetic or economic
.
"You never hear anybody talk about mad tofu disease." 
"Consider the biggest animals on the planet: elephants, and buffaloes, and giraffes. These are vegetarian animals. They grow to thousands of pounds of muscle and bone without ever eating cheeseburgers and pepperoni pizzas."
"I am a vegetarian for health reasons - the health of the chicken."
"Some say if animals are not used for food they will overrun the earth. In India the Hindus do not kill cows, but they are not overrun by them."
"[The animals] are now especially bred for eating purposes, and if the demand decreased, the supply would decrease also. Further, how is it that we are not overrun by wild animals of all sorts? […] People need not worry about the future welfare of the bovine race, if they would only be a little more humane in their treatment of its present representatives!"
"If eating meat why not eat the most highly organised form of meat, which is not beef or mutton, but human flesh? If you still believe in the eating of flesh, then you must admit that at least as far as the fitness of food is concerned the cannibal has the best of the argument."
"The Animals, you say, were “sent” For man’s free use and nutriment. Pray, then, inform me, and be candid, Why came they aeons before man did, To spend long centuries on earth Awaiting their Devourer’s birth? Those ill-timed chattels, sent from Heaven, Were, sure, the maddest gift e’er given – “Sent” for man’s use (can man believe it?) When there was no man to receive it!"
"Vegans and vegetarians are commonly baited by nonvegetarians with “what if” scenarios that typically have no relevance to or bearing on most people’s real-life situations."
"I was told that my diet was so poor that I could not repair the bones that were broken and operated on. So I have just had an Xradiograph taken; and lo! perfectly mended solid bone so beautifully white that I have left instructions that, if I die, a glove stretcher is to be made of me and sent to you as a souvenir."
"The average age of a meat-eater is 63. I am on the verge of 85 and still at work as hard as ever. I have lived quite long enough and am trying to die; but I simply cannot do it. A single beef-steak; would finish me; but I cannot bring myself to swallow it. I am oppressed with a dread of living forever. That is the only disadvantage of vegetarianism"