I think it would be practically impossible to do a boring biography on the Kellogg brothers. Dr. John Harvey Kellogg alone would make for a great show--with his odd combination of very prescient views about good health and insane ones! And, Will Kellogg's success in life as a sort of 'Cereal King' is also quite interesting and inspiring.
Dr. John Harvey Kellogg blended the views of the Seventh Day Adventist Church with his own philosophies about medicine--creating a world-famous sanitarium where the rich and trendy mixed with the common folk in the name of healthy living. On the positive side, he popularized vegetarianism, exercise, sunshine and abstinence from alcohol. On the negative, he was possibly nuts (though the show never says this or even intimates it) and many of his nuttier practices are ignored or underplayed in the show. He loved colonics and prescribed TONS of these enemas! In fact, he felt that the intestines were evil and even, in some cases, removed them entirely from his patients! He also though sex was evil and draining and declared that he NEVER had sex and masturbation led to insanity!! He also created several quack devices--including static electricity cages! And, finally, he became a great proponent of the eugenics movement--a philosophy that only the best people be allowed to breed. Why the show chose to ignore or de-emphasize these strange aspects of the Doctor, I really do not understand.
Will K. Kellogg came to work for brother as his assistant. However, the Doc was apparently quite dictatorial and unappreciative of Will. Eventually, Will took many of the Doctor's recipes for cereals that were served at the sanitarium and marketed them--making a fortune in the process. As a result, the two brothers became estranged--which is pretty sad. Eventually, Will became quite rich and John fell into obscurity.
Aside from missing many of the stranger aspects of John Harvey Kellogg, the film also suffered from the overuse of static photos (unlike many PBS shows which seem to make the pictures come to life through a roving camera). But, there was still a lot of interesting content and I never got bored while watching. Well worth seeing but you'd do better reading up on the brothers--so much was omitted.