I am thinking about starting a vegetarian diet. This means I would not consume the flesh of any animal.
That sounds healthy!  What are the advantages of a vegetarian diet over eating animal protein?
I'm not sure of the specifics, but health is only one reason for adopting a vegetarian lifestyle. Other motivations are political, cultural, or economic. 
What would be an example of some of these reason?  Is it cheaper to eat a vegetarian diet?
Yes and no. While many people save money from not buying meat, supplementing the vitamins and protein meat gives you can be expensive.
That is true.  Supplements are crazy expensive.  What political reasons are the for this kind of diet?  Is it because people don't want to harm animals?
Vegetarian ecofeminism
Vegetarian ecofeminism is an activist and academic movement which states that all types of oppression are linked and must be eradicated, with a focus on including the domination of humans over nonhuman animals. Through the feminist concept known as intersectionality, it is recognized that sexism, racism, classism, and other forms of inter human oppression are all connected. Vegetarian ecofeminism aims to include the domination of not only the environment but also of nonhuman animals to the list. Vegetarian ecofeminism is part of the academic and philosophical field of ecofeminism
Vegetarian diet.
Hinduism does not require a vegetarian diet, but many Hindus avoid eating meat because they believe that it minimizes hurting other life forms. Vegetarianism is considered "satvic", that is purifying the body and mind lifestyle in some Hindu texts.
Lacto-vegetarianism is favored, which includes milk-based foods and all other non-animal derived foods, but it excludes meat and eggs. There are three main reasons for this: the principle of nonviolence (ahimsa) applied to animals, the intention