One of the paleo meals I took to the hospital to eat mid-shift
Medical student Kris Gunnars has an article at Business Insider, of all places, that shows graphically many of the major U.S. dietary changes of the last hundred years or so. In this case, transmogrification may be a better term than mere “changes.” In short, we’ve moved even further away from the Paleolithic diet. I suspect much of the entire Western world diet has evolved in similar fashion.
You need to read the article and ponder the graphs if you question why we have so much obesity, type 2 diabetes, heart disease, hypertension, and perhaps cancer. You’ll see dramatic increases in consumption of added sugars, industrial seed oils (esp. soybean), soda pop and fruit juice (added sugar!), total calories, and fast food. You’ll see how much we’ve increased dining away from home. Butter consumption is down drastically, but doesn’t seem to have done us much good, if any.
Sugar cane
There’s fairly good evidence that coronary artery disease (CAD; the cause of most heart attacks) was very prominent between 1960 to 2000 or so, but it’s been tapering off in recent years and didn’t seem to be very common 100 years ago. Understand that you can have it for 20 years or more before you ever have symptoms (angina) or a heart attack from it. In fact, the disease probably starts in childhood. I’ve always wondered about the cause of the CAD prevalence trends, and wondered specifically how much of the long-term trend was related to trans-fat consumption. But I’ve never been able to find good data on trans-fat consumption. Kris came up with a chart of margarine consumption, which may be a good proxy for trans-fats. Another of his charts includes shortening, a rich source of trans-fats and probably also a good proxy. Shortening consumption increased dramatically from 1955 until dropping like a rock around 2000.
The timeline curves for trans-fat consumption (by proxy) and prevalence of coronary heart disease seem to match up fairly well, considering a 20 year lag. In the early 1990s, we started cutting back on trans-fats, and here we are now with lower mortality and morbidity from coronary artery disease. (CAD is very complex; lower rates of smoking surely explain some of the recent trend.)
Read the whole enchilada. Very impressive. Highly recommended.
Paleo Diabetic 
I read the article and I really enjoyed it. Some of his points were familiar to me and others were either new or presented in a different light which caused me to think. I definitely think the biggest change for the worse was the damnation (hope I can say that) of traditional fats, especially animal fats. When I was young, there was added sugar to coffee and tea. Kool aid drink was made with water and added sugar. Of course, one’s mom got to decide the amount of sweetness in that drink. I had cake and ice cream at birthdays but I don’t remember anyone who was fat or pudgy, especially as an adult. I think the addition of sugar to processed goods to make up for the lack of fat has also had a deleterious effect on people’s health, which brings us back to the lack of good fat — whether it be lard, coconut oil, or palm oil. Sometimes I wonder if wheat really is the bogeyman its set up to be or perhaps my number 2 villain — soy everything! – is the problem. Hard to say unless one does self experimentation.
Thanks for posting the article.