Your friend is a vegetarian who consumes large quantities of soy products in the place of meat. From a nutrition perspective, your friend is at risk of developing protein and iron deficiency.
Explanation:
Meat has some nutrients that may be lacking in ailments like soy. Some substances are better absorbed by animals, for example proteins and iron. Vitamin B12, a type of protein, is needed for the production of DNA, and it is absent in soy. Vitamin D is important for calcium absorption but soy products don't contain this. Finally meat products have two forms of iron heme and nonheme and Plants contain nonheme iron only. The heme iron is the most easily absorbed.
The relationship between a remora and a shark is an example of commensalism - it's good for one side but neither good nor bad for the other. The remora attaches itself to the shark and gets the benefit of eating the shark's leftovers, but there is no harm or benefit for the shark, and the shark doesn't eat the remora like in a predator/prey relationship.
