Do you still believe in calories? I do. I understand that there are exceptions to the rules such that protein calories may not be metabolized as rapidly as those from alcohol, carbohydrates and fats. I also understand that there are variations in metabolic rates from one person to the next. Some of us can eat massive amounts of calories without gaining weight, while others seem to add pounds with minimal calorie intake. Exercise also helps us keep off unwanted pounds, although the role of exercise in weight control is controversial. Having said all that, the single best way to assess how food contributes to weight gain is to monitor calories consumed vs. calories burned.

To that end I am using a report out of Harvard which lists the top 10 sources of calories in the American diet. To get a little more perspective I went back to their original source, a report of the Dietary Guidelines Advisory Committee. The data that form the basis of these numbers are almost 20 years old, but they are the best I have. There were some surprises to me on the list. Here is the list and my attempt to contextualize it in terms of processed food.

10. Dairy desserts are an American obsession. We eat large quantities of ice cream. At least when the survey was taken, we consumed more calories from dairy desserts than from burgers (number 12 on the list). There are also data available for different age groups. I note with interest that it rises to the third highest source of calories for people above 70 years of age. It is not clear to me whether people who live longer tend to eat more ice cream or when they reach 70 they figure they have earned it. When I celebrate my 70^th birthday later this year, I may want to start consuming more ice cream! Make mine chocolate marshmallow.

9. Beef and beef-mixed dishes come in next. Missing from this category, however are burgers which we find at number 12 as noted above. This category also excludes burritos, tacos and other dishes associated with Mexican cuisine. Fries, America’s favorite vegetable, come in at number 17. Somehow, I would have thought beef would score higher than number 9, but if you add in burgers with beef and its mixed dishes, the combined category jumps to spot number 4. The way foods are grouped together in the advisory report can be misleading.

8. Mexican mixed dishes include burritos, tacos, enchiladas etc. Thus, beef and chicken wrapped in a tortilla fit here rather than as a beef or chicken dish. With the increase in fast-casual Mexican chain restaurants like Chipotle and the influx of immigrants from south of the border, this category may even be higher today than when the survey was taken. I’m not sure where other Latino-inspired foods would fit. Although there are many processed Mexican products available, I suspect that restaurant foods and homemade items dominate this category.

7. Pasta and pasta dishes are now accepted as an integral part of American cuisine and distinguished from their Italian roots. I am not sure if pasta still outcompetes Mexican dishes, but I suspect that the processed products are more significant here than the previous category. Macaroni and cheese after all would be included.

6. Alcoholic beverages as this significant a source of calories surprised me. I mean maybe in college towns, but across the whole country including dry counties? Thus, beer, wine and other sources of alcohol constitute a greater source of calories than burgers. Aside from mention of a beer gut, alcohol is rarely associated with obesity, but I suspect that it is a more significant factor in our corpulent society than fast food among adults.

Photo by Sara Yang

5. Pizza breaks the top five, and it will come in as no surprise that it is the greatest source of calories for adolescent boys! I suspect that restaurant pizza dominates the category with processed frozen product coming in next. Then there are components that can be put together for convenient home preparation, but many of these ingredients would also fall into the processed category. Even though I am past adolescence, pizza remains my favorite food, but I keep it as an occasional treat rather than as a staple in my diet.

4. Soda, energy drinks, and sports drinks are another huge category, the largest for beverages. Note that these products include diet drinks as well. Since sugar is the main source of calories here, soda and energy drinks would seem to be prime candidates for calorie reduction. Soda taxes are being levied to serve as an incentive to reduce calorie consumption and/or to produce needed revenues for cities. When diet sodas are included in the tax, the motive appears to be as much about revenue as it is about calories. Taxes on sugared beverages appear to work initially, but it is not clear that they are effective in improving health of a community. All products in this category are considered to be processed.

3. Chicken and chicken-mixed dishes are our primary source of meat calories even when we combine beef dishes with burgers. Once again, chicken quesadillas and similar dishes fit into the Mexican category and not this one. Chicken is probably the greatest single source of whole food calories. Restaurants and home preparation probably account for most of these dishes. Frozen chicken dishes and canned chicken soups help round out the category.

2. Yeast breads are distinguished in the list from quick breads (leavened with baking powder). The major criticism of breads and buns in popular culture is the presence of gluten, but I suspect few consumers consider them as the second leading contributor to calories. Our bread obsession, particularly our reliance on sandwiches, is likely a major contributor to obesity—even more than sodas! In addition, bread is the number one contributor to sodium in the American diet, which is a major reason why processed foods contribute to our overconsumption of sodium.

1. Grain-based desserts (cakes, cookies, donuts, pies, crisps, cobblers and granola bars) top the list. If you are wondering where most of the sugar comes from in the American diet, it is from grain-based desserts, sodas and dairy desserts. Most so-called junk foods could fit into these three categories. Note that all commercial grain-based desserts are processed. Home-baked desserts, although not as prevalent as in the past, are still a major contributor to sugar and calorie consumption in the country.

For some perspective only two of the top ten sources of calories in the American diet are predominantly whole foods—beef and chicken. Three out of the top four sources— carbonated beverages, bread, and grain-based desserts—are essentially from plant-based ingredients. Four of these categories—dairy desserts, alcohol, carbonated beverages and grain-based desserts could be appropriately labeled as junk foods. I defend pizza as it frequently represents a balance of nutrients, but it is frequently overconsumed particularly when accompanied by copious amounts of beer.

So, yes, processed foods are contributing to our obesity epidemic and our overconsumption of salt, but not all processed foods are junk and not all junk foods are processed. Note that neither fruits nor vegetables make the top ten individually or combined. Actually, neither group show up in the top thirty unless you count French fries at 17 and other white potatoes at 28. Combined, potatoes would come in at 9 ahead of beef and beef-mixed dishes. Part of the problem with this list is how foods are grouped. For example, I don’t see how burgers are separate from beef or from buns. I do think the list provides some insight into what could be contributing to our collective weight problem and where we might focus our efforts. I also wish the data was more up to date to see how the American foodscape is changing. Are we getting better or worse in where we take in our calories?

Next week: The Poison Squad: One Chemist’s Single-Minded Crusade for Food Safety at the Turn of the Century