How many infections does a teenager with stress get on average a year ?. is 6 colds a year concerning ?

Probably OK: The average person gets some sort of upper respiratory infection every 6 to 8 weeks depending on exposure. Sounds pretty normal. If they are more complicated than just colds, your physician can advise you better.

Treat the Stress: Stress weakens the immune system. The teenagers needs therapy and life experience to treat the stress.

Not really: Six upper respiratory infections a year is really not all that unusual, especially if you are still in school where all types of germs are passed freely around. What bothers me more, though, is the statement "with stress". The teen years should be years of fun, excitement and exploration of who you are, not chronically stressful. You may want to think about talking with a professional about this..