Here's a little something to think about...
Those of you who were pregnant in the between 1940 and 1970 may know of a drug called Diethylstilbestrol (DES). It is a synthetic form of oestrogen that was given to pregnant women because it was thought to prevent miscarriage. Many women didn't even know they were given it because it was routinely given as part of a prenatal 'vitamin' injection in both the US and UK.
And babies were born that looked normal and healthy with the exception of an increase in hypospadia in boys. Years later when the girls born of Mother's given DES (DES daughters) were becoming pregnant it was found that the drug had caused changes in the uterus of those girls that resulted in difficulty conceiving, an increased risk of miscarriage, and an increased risk of a rare form of uterine cancer, and an increased risk of breast cancer. That resulted in a class action suit in the USA and banning of the drug for use in humans. It continued to be used in vetrinary medicine and is still in limited use to this day.
What they didn't know at that time was that DES was a systemic teratogen that caused epigentic changes to the endocrin systems of both the Mothers and babies which are still being found in fourth and fifth generation offspring of the babies born to Mothers who were given DES. In mice epigenetic changes have been shown to last eight generations or more before they start to resolve.
The effects of DES on the reproductive system have long been known, more recent studies have shown that another of the effects of DES is adult onset obesity. It is also suspected that there is a link to Type 2 diabetes, polycystic ovarian syndrome (PCOS), and hyperprolactinemia/prolactinoma.
What is scary about all of this is that DES continued to be used in vetrinary medicine for another 25 years after it was banned for human use. It was used to increase milk production in dairy cattle and was present in the milk from those cows but thought to be at a harmless level. Everyone who consumed milk during the years it was used in the dairy industry has been exposed to DES and may have acquired the same epigenetic changes and Mothers and babies exposed to DES and will have passed those genetic changes to their children. And being a synthetic version of oestrogen, DES doesn't break down as easily in the environment as natural oestrogen. It has been found in lakes and rivers in detectable amounts, no doubt from the use of manure as fertiliser and the resulting runoff.
It's entirely possible that we are not eating ourselves to death because of junk food and inactivity, but rather because of something that was thought to be a beneficial medication that turned out to a liability that will last for generations. DES is just one of many possible known factors that are contributing in some way to the so called obesity epidemic and increase in T2 diabetes.
At the end of it all, I am a DES daughter and I have PCOS, hyperprolactinemia, and T2 diabetes. I am the fourth generation of my family to be a T2 so I don't think that DES is entirely to blame for that, but I do think it has complicated the condition. As a result of that genetic history I have chosen not to have children so that I don't pass that burden on to another generation. All I can do is live with what I have and that means that what is a normal healthy diet for anyone else is not a healthy diet for me.