My mother, who never used a computer in her life until she was in her late sixties, and even then used them rarely, maybe an hour a week, and who almost never watches television, has had serious Chronic-Fatigue-Syndrome since her thirties. She also developed thyroid problems, IBS, diverticulitis, heart disease and probably some other stuff I don't know about.
And she's hardly ever used a computer.
So I guess computers aren't the ONLY source of illness...