The benefits vary from - you will die if you stop meat eating - to - except vegetables everything else is only poison. But still there are some clear benefits that are accepted by everyone.
The most known benefit of vegetarian diet is that it contains lesser fat compared to meat. So it avoids the problems that most people are facing today. It essentially helps maintain a lower body mass index value. Many people choose to become vegetarians due this reason.
The other benefit is reduction of cholesterol level in the body. This reduces the chances of a heart attack. Also the vegetarian diet reduces the probability of getting diseases like high blood pressure, certain cancers, adult-onset diabetes, obesity etc.
Perhaps of the well-known benefit of vegetarianism is the increase in longevity. Those who take only vegetarian diet live longer than non-vegetarians.
Vegetarianism also has advantages for the environment. If you want to go green, go veggie. Meat production is not only cruel but it also brings with it the destruction of ecology and environment. Green is the need of the day now. So one needs to be aware of this.
Also vegetarianism doesn't mean that one should live like that in poverty. Even in vegetarian diets we can find delicious foods. Only one needs to learn what to make and how to make. Considering these things we can see that vegetarianism gives more than what it takes. So why not become a vegetarian?
