[1] As a psychology professor, Roberts read a report by Israel Ramirez, a scientist at the Monell Chemical Senses Center, about the effect of saccharin on the growth and weight of rats.

The theory is based mostly on self-experimentation data that led him to conclude a relationship with calories consumed and "flavor" programmed by the brain.

He noticed in himself a significant loss of appetite and speculated that it was due to experiencing unfamiliar flavors of soft drinks that were not available to him in the USA.

Seth Roberts focused entirely on the psychology of the association by the brain with calories and familiar flavors and that effect on the setpoint.

Roberts states that the diet is based upon connecting two unconnected fields: weight control and associative learning.

[12][13][14][15] Roberts was criticized by UCLA medical professor John Ford on the fact that it had not been subjected to scientific peer review.

[16] In an interview on the Canadian Broadcasting Corporation's Sunday Night program, nutritionist David Jenkins also criticized the lack of scientific research validating the diet.