I increasingly think not only food composition but also availability has something to do with it. For example, as a kid in the 1950s and 60s, there were just a few cereals available: corn flakes, Rice Krispies, grape nuts, a few others. Now you pass down the cereal aisle and I can't believe how many cereals there are, a great many of them sugared. Then there are the chips...I remember just potato chips and Fritos, not a lot else. Look at the chip aisle now...again, just as bad as the cereal aisle. And then there are the cookies, the candies, the list is long. Also consider the sizes of all these products. I remember when I was a student in France in 1974, the markets had tiny little bags of chips, nothing larger than the little individual serving chip bag size you see now. Cookie packages were small, with maybe 15 cookies in them. Cokes and sodas were SMALL, maybe 6 oz bottles. So the list is long. I read a study that mentioned if you were given a huge bag of popcorn, people tend to eat it, whereas they would have been satisfied with a much smaller one. So perhaps with a greater volume of food available in a purchased item, you'll just sit there and eat it. And of course, then you get in a spiral of blood sugar spikes and that leads to more eating when the spike drops. People's perception of what a normal serving should be is now distorted.

Anyhow, I look at serving sizes and all that, and sometimes I'm shocked at the amount of food people can and will eat in one sitting. I think people believe they need more food than they really do. My husband and I started splitting meals when we occasionally eat out. We found we are more than satisfied with the smaller amount of food each, and the bonus is it's cheaper to eat out that way!