Nutritional reasons
One of the most popular arguments are where people will crib that vegetarian food lacks omega 3 fats, and that it can only be acquired through seafood. That is a fallacy. Omega 3 fats are abundantly found in flax-seed oil and olive oil. So the next time you are making pizza or pasta at home, make sure to sprinkle some olive oil!
Now we come to the most popular argument of meat eaters- Protein ! Yes, protein is a very essential component of our body, and especially so for growing kids. I know plenty of people who lead a very active lifestyle, playing competitive sports, bodybuilding etc, and they are pure vegetarians. The staple Indian meal of dal, chaval, sabji and roti suffices more than enough for the body’s protein requirement.
Amino acids are the building blocks of proteins, curd(yogurt) contains every single essential amino acid that the body requires, and there is no meat product that even comes close to providing these nutrients. For my vegan friends out there who do not consume milk or milk products, or feel they lack protein in their diet, they should simply eat more pulses, lentils, beans and grains, and that will serve their requirement.
One is often under the impression that Vitamin D can only be found in meat products (especially seafood), and not in any other vegetarian food. That is true, but fortunately, taking a 3-5 minute walk in the morning or evening sunlight as little as a couple of times a week is enough to synthesize the Vitamin D that we need, and it certainly is worth (not to mention healthy) to talk a walk. Five minutes is the least one can spare to save a life each day.
Ecological reasons
One might say eating plants is killing life too. Unfortunately, it is, and it is the only way we can live. Now, let us take a look at the following line of logic
A vegetarian eats ‘X’ number of plants.
A Non vegetarian not only kills ‘Y’ number of animals, but also in the process of animal husbandry, they feed the animals at least 40 ‘X’ amount of vegetarian food as the animal’s weight, and then eat the animal as well. So if a vegetarian has killed ‘X’ number of plants, a non vegetarian has killed minimum ’40 X + Y’ number of plants and animals. Which is the greater sin? That I’ll let you figure out for yourselves.
Let me explain using the example of a chicken. Chickens are especially reared in poultry farm, in numbers far greater than their natural population; so as to not inconvenience people who would like to eat them. The chickens are fed a large number of worms to increase their mass and to fatten them up for consumption. These worms in turn feed on an even greater amount of plant and organic matter, on land which could otherwise have been used for growing crops. Let us look at the equation again in this new light and calculate the damage done. Vegetarians consume ‘X’ plants, non vegetarians consume ‘Z chickens + Z.Y worms + Z.Y.X plants’. Does this sound unbelievable? I know it does, and yet it is very unfortunately true. These numbers too are the lower estimate approximations that I have given. A human being consumes on average 36,000 kgs of food in a lifetime, so you can imagine the harm done in eating meat.
If we grew crops on all the land that was being wasted to feed non-vegetarians, there are studies which show that the world food crisis would come to an end. Every man, woman and child would have food to eat. Other studies have also shown that the factors involved in producing non vegetarian food (waste of crop land, waste of natural resources, transportation, etc) are the leading causes of global warming, which too would stop if everyone became a vegetarian
Moral reasons
Non vegetarians claim that plants have nerve endings and can feel pain. This is an unqualified assumption of facts that do not exist. For example, when you touch a mimosa (a touch-me-not plant), the reason it curls up isn’t because it feels something and it consciously decides to close its leaves, it is due to the potassium ion chain, that when applied pressure to the cell wall there will be a transfer of ions and it will act as a lever to close the leaf. A plant has no central nervous system- meaning it has neither brain, nor nerve endings, and hence no sensation of pain. It is a well established fact that animals feel extreme pain, not only when they are being slaughtered, but also during the long periods they are held captive. Pigs are battered with rods in order to kill them. Piglets are lifted and thrashed head first onto the ground. Cows are shot at with stun guns, often they do not die from the first assault and have to endure extreme pain until the time they are hit again. Roosters, chickens, ducks are immersed in a steaming cauldron and boiled alive so their feathers are plucked easily. These are only few of the ways animals are mistreated, there are several more which cannot be listed due to space restraint.