BNguyen said:
it's all about morals and preferential tastes,
even if a person is born in a culture which prohibited eating meat, that doesn't necessarily mean that they like the taste of vegetables, grains, and fruits
then there are the morals
some see it as an evil to kill animals for nourishment, although, these people fail to look at nature and realize that we as animals are part of nature. animals eat other animals but we are one of the few species which eats both meat and plants, but first and foremost, our anatomy was designed for eating meat.
Some may say eating only vegetables is healthy but lack of meat or on the basic level, protein and iron, is detrimental to one's health and these cannot be obtained in sufficient levels without eating meat.
I beg to differ.
And yes, I'm going to copy and paste this.
Some might expect that since the vegan diet contains a form of iron that is not that well absorbed, vegans might be prone to developing iron deficiency anemia. However, surveys of vegans 2,3 have found that iron deficiency anemia is no more common among vegetarians than among the general population although vegans tend to have lower iron stores 3.
The reason for the satisfactory iron status of many vegans may be that commonly eaten foods are high in iron, as Table 1 shows. In fact, if the amount of iron in these foods is expressed as milligrams of iron per 100 calories, many foods eaten by vegans are superior to animal-derived foods. This concept is illustrated in Table 2. For example, you would have to eat more than 1700 calories of sirloin steak to get the same amount of iron as found in 100 calories of spinach.
Another reason for the satisfactory iron status of vegans is that vegan diets are high in vitamin C. Vitamin C acts to markedly increase absorption of non-heme iron. Adding a vitamin C source to a meal increases non-heme iron absorption up to six-fold which makes the absorption of non-heme iron as good or better than that of heme iron 4.
Fortunately, many vegetables, such as broccoli and bok choy, which are high in iron, are also high in vitamin C so that the iron in these foods is very well absorbed. Commonly eaten combinations, such as beans and tomato sauce or stir-fried tofu and broccoli, also result in generous levels of iron absorption.
From http://www.vrg.org/nutrition/iron.htm#vegans