The protein myth (that vegetarians don't get enough protein) was introduced in 1971. In 1991 the author of the book that created the myth retracted her statement but the idea will not die: http://www.diseaseproof.com/archives/diet-myths-complementar...
> A dangerous myth
To wrongly suggest people need to eat animal protein for nutrients will encourage them to add foods that are known to contribute to the incidence of heart disease, diabetes, obesity, and many forms of cancer, to name just a few common problems.
The World Cancer Research Fund and American Institute for Cancer Research published a report linking diet to cancer. http://www.dietandcancerreport.org/pr/?d=overview Unfortunately, I can't find the details easily accessible online, but there is a nice summary in the book Becoming Vegan. The basic findings were that increasing your intake of fruits and vegetables tended to prevent cancer and eating more meat tended to increase certain kinds of cancer. More specifically, they were able to link meat-eating to increased risk of breast, colon, prostate and pancreas cancer.
I'm also under the impression that the typical American's diet is out of balance--eating too much meat and not enough fresh fruits and vegetables. The protein myth could encourage people to add more meat to their diet when they may need to cut back.
