The average adult in the U.S. today is 24 pounds heavier than the average 1960 adult. Two-thirds of us are overweight, half of whom are obese. We are fat.

We’ve tried low-fat diets but the problem just got worse. The $20 billion diet industry offers all kinds of approaches to weight loss just a mouse click away.

But instead of asking how we can stop being fat, maybe we should ask why we got so fat. Then, with a little reverse engineering, we can chart a course toward a healthier weight.

So what changed? What made us gain an average of 24 pounds in half a century?

Fortunately for us, the USDA has done the homework and provides a handy report to work from. Chapter 2 of the USDA Agriculture Factbook is titled Profiling Food Consumption in America, and that’s exactly what it does.

The chapter gives us detail on exactly what we’ve been eating since 1950, how much of it we’ve been eating, and how it’s changed over time.

I’m going to get straight to the punch line here because everything else needs to be considered with this in mind. The USDA found that we are consuming 800 calories more per day than we did in 1957, and 500 more calories per day since 1970.

That’s an astounding shift in intake – an almost 25 percent increase in just the 30 year period from 1970 to 2000.

I know that the calories-in/calories-out theory of weight gain has taken a beating lately, but I don’t believe there is any way a reasonable person can look at these numbers and say that calorie intake isn’t part of the problem.

So now that you know the end of the story, let’s go back and look at some details. Those additional calories aren’t coming from all foods equally and there are some lessons to be learned from these numbers.

Meat and Egg Consumption

If you take a look at the chart below, you can see that for all our talk about eliminating saturated fat, we actually eat more red meat. We just added a ton of lean poultry to try to make ourselves feel better about our choices.

This increase is coming in the form of portion size--- I doubt that many of us have added multiple meals during the day.

Meat and Egg Consumption

Changes in Consumption of Dairy Products

We did listen to the cries about saturated fat when it comes to dairy products. We dropped our total dairy consumption by 15 percent, a big chunk of which came from full fat milk and those space age favorites, evaporated and condensed milks. Instead we’ve been treating ourselves with lots of cheese – we get a lot of it from dining out and from convenience foods like pizza and tacos.

Consumption of Dairy Products

Changes in Fat Consumption

We’ve bumped up our fat intake by a whopping 67 percent! This in spite of all those low-fat recommendations. There’s also been a clear shift in the type of fat consumed. Salad and cooking oils skyrocketed, again probably impacted by dining out.

Plus, we shifted from the naturally occurring lards and butters to shortening and margarine. Margarine was again on the decline in 2000 after its peak in the 70s, when the dangers of trans fats became clear. But shortening will endure as long as our love of deep-frying.

Changes in Fat Consumption

Fruit and Vegetable Consumption

In keeping with the “Eat More” trend of the past half-century, fruit and vegetable consumption increased. But, sadly, it was not to the same extent as our overall calorie intake.

Fruit and Vegetable Consumption

Grain and Sugar Consumption

And finally we get to grains and sugars. Again, remember that we did not decrease our fat consumption or our red meat consumption. So this is in addition to the diet we were already consuming.

Grain and Sugar Consumption

Let’s dig into the sweetener category a little deeper:

Artificial Sweetners

Corn sweeteners, aka high fructose corn syrup and its ilk, are a new entry into our diets, accounting for a massive increase in caloric intake.

The Takeaway(s)

That’s a lot of data, but it takes a lot of data to describe a lot of food. As expected we are consuming more calories in nearly every category. But here are two key points to notice among all these numbers.

First, we never really decreased our saturated fat consumption. We continued to eat red meat, and just added leaner protein instead of substituting it. We also shifted from naturally occurring fats such as lard and butter to hydrogenated fats in the form of shortening, et al. And we started cooking with a lot more oil and putting more of it on our salads.

Second, we added a ton of calories in the form of grains and corn sweeteners - foods that are quickly absorbed and spike insulin levels.

So, in addition to the idea that we need to quit eating so much, maybe we need to quit eating so much of certain things. We need to cut down our portion sizes across the board, no doubt. But more specifically, we need to remove a good portion of grains and sweeteners, as well as added fats like shortening and cooking oils.

Will these steps roll back the obesity epidemic? It’s a good start.

Amy Rogers MD is not a practicing physician and nothing written here should be taken as medical advice from either Amy or AssetBuilder. Medical decisions should be made with care in consultation with your health care provider.