Semi-vegetarianism section 

I like Flyer22's intention in that one's recent edits, though I find the particulars a little unclear. Here is my proposal for the section (  ):
===Semi-vegetarian diets===
Semi-vegetarian diets primarily consist of vegetarian foods, though occasional exceptions are made for some non-vegetarian foods, including fish, poultry and even red meat. These diets may be followed by those who choose to reduce the amount of animal flesh consumed as a way of transitioning to a vegetarian diet, or for health, environmental, or other reasons. The term "semi-vegetarian" is contested by most vegetarian groups, who believe that vegetarianism must exclude all animal flesh. Many individuals describe themselves as "vegetarian" while practicing a semi-vegetarian diet. Semi-vegetarian diets include: 
 Flexitarianism: A diet that consists primarily of vegetarian food, but includes occasional exceptions such as red meat.
 Pescetarianism: A diet that is mainly vegetarian but also includes fish and sometimes other seafood.
 Pollotarianism: A diet that is mainly vegetarian but also includes poultry.