Not just obesity specifically but I was just thinking about this recently, the negative effects on each generation of the foods that were popular at the time but later found harmful. My mom in her 80's expressed surprise that I'm starting to have age-related health problems in my 50s. That in turn surprised me because I had assumed she did then, too and that it was normal. She was raised on a farm with no choice but all natural foods, that was all there was. I in turn grew up with Crisco, margarine trans fats in everything. Now the next generation after me I've been surprised to see serious health problems developing in the 20s that I still don't have. Raised on inflammatory soybean oil, trans fats and carbs because that's what we thought was good for us. Generation after that being fed really well because their parents figured out from everyone's not so fun experiences of the past.