The Road to Wellville (1994) on Netflix

In Welville, at Battle Creek, eccentric rich Dr. John Harvey Kellogg (a historical figure) runs a stylish health farm for the wealthy, an idea ahead of his time, based on extreme vegetarianism, neither sex, masturbation or even sensual stimulation, but laughing therapy and purging the 'polluted' body, mainly by exercises, often in open air, vicious diet, his invention corn flakes, laxatives, anal yogurt cure, enemas and brutal mechanical cleansing. Eleanor Lightbody drags her sickly, incredulous husband Will along to the therapy; the couple is almost immediately separated and getting horny for more available members of the opposite sex. Kellogs stubbornly willful adopted son (among over 30 kids) George is a filthy embarrassment, paid off just to stay away. Charles Ossining panics when arriving in Battle Creek he finds his aunt's fortune made him partner in the empty shell- health food company Per-fo, not the planned corn-flakes factory; however with a former Welville-employee and George's name they hope to get rich from their own cornflakes brand. When an electric therapy goes fatally wrong and several other patients die, Will's incredulous reluctance turns to panic...