Why is it a good idea to be a vegetarian?

I personally am not a vegetarian, but I have a very good friend who is. she believes that being a vegetarian makes you healthier, and you cannot get certain diseases, such as salmonella

To Bypass poisonous food: Uncooked meals are filled with nasty toxins and contaminants like fungi, herbicides, little bacteria, and bacteriostats. While certain venoms are full of fat-soluble, they all accumulate in the greasy meat of the animals. Not to state the microorganisms, bacteria and saprophytes before-mentioned as hookworms, and toxoplasmosis parasitoids.