I am a nutrition researcher and have been for 30 years and it is my professional opinion that you are not correct. For example heme iron is absent from a vegetarian diet. Heme iron is necessary for normal red cell production and utilization. Certain forms of vitamin B12 are not bio-available from foods that are not derived from animals. Cholesterol and saturated fat, which are needed by the body to cope with and reduce oxidative stress, respectively are not present in a vegetarian diet. Moreover, cholesterol is necessary for the absorption of fat-soluble vitamins, proliferation of neural connections, thermoregulation and many other vital functions that humans cannot live without. So, no, vegetarians are not healthier. If you know a vegetarian who is healthy, that is analogous to a situation in which a person who crosses the street when the light is red everyday is not killed and assumes that crossing on the red light is safe, when in reality, it just means that this person has been lucky so far.