The American diet has changed drastically over the course of the past few decades. This is in no small part due to changes in agricultural production and food marketing.

Today more than ever, Americans live in a land of plenty. As of 2006, the average American spends 9.6 percent of his or her income on food. In the 1960s, that percentage was 17.5 percent. All of this cheap food and targeted food marketing has helped usher in the obesity epidemic.

If you wanted to lose weight in the 1990s, marketing told you low-fat was your friend. So carbohydrates began to replace them and companies started producing low-fat products. But, to make them taste good, sugar was swapped in — and these products flew off the shelves.

Unfortunately, not only did people stay overweight, they became even more unhealthy.

And so began the chapter where carbohydrates and sugars became the enemies. The past two decades saw the boon of the low-carb diet trend and an increase in sugar-free foods. Despite these trends, the consumption of high-fructose corn syrup has seen a larger increase in consumption since the 1970s than any other food.

With regard to produce, though, it looks like Americans are taking a step in the right direction. Fresh fruit and vegetable consumption is on the rise, while consumption of canned and processed versions are on the decline.

To determine which foods experienced the biggest rises and falls in consumption from the 1970s to 2013, the experts at HealthGrove, a Graphiq data analysis site, crunched the numbers from the USDA Economic Research Service.