Were the public relations tactics of the food industry ethical? Why or why not?

I am always amazed when I watch a documentary about something I think I already know, then learn so much more. The role that the sugar industry and advertising played during the 1940s to 70s was astounding. There were so many mixed messages and lying on a disturbing scale when it came to sugar. The use of beautiful models telling their audience that a bottle of Coke had no more sugar than a grapefruit and won't hurt waistlines just goes to show you that our society has been constantly peppered with the illusion that sugar was good for us. The amount of time and money spent to cover up what was going on in the food and beverage industry was astounding to me. In the 1960s when the data was finally being pieced together that sugar was bad for someone, scientists like Yudkin were being silenced by the food and beverage industry by sponsoring research that contradicted the claim that sugar was harmful. Even worse was the financial support given to scientists like Keys claiming sugar was not the enemy. The marketing, packaging, and advertising were undoubtedly unethical and still are. Now we finally have the science saying that sugar is deadly in large quantities, but unless corporations sell and distribute responsibly and honestly, this will likely only continue leading to further metabolic diseases for generations to come.