W.L. Rathje

By W.L. Rathje

The Garbage Project has collected and studied fresh household refuse and excavated and analyzed landfilled MSW across North America and in a few spots around the world for three-plus decades.

In the process, we have revealed and unearthed many unexpected findings—that we all waste significant quantities of food, that what we say we eat and drink often differs from the remains of our consumption by 30% to 50% or even more, that paper doesn’t biodegrade rapidly in well-run dry landfills, and more.

But until recently, there was only one “unexpected finding” that I could not fathom in any fashion: that our garbage data from the highest-income neighborhoods in Mexico City indicated that household residents ate between two and four times more food per person than residents of middle- or lower-income neighborhoods. Whoa!

Excesses with such extravagance? Did the student sorters not record the refuse accurately?

I didn’t think so. In 1980, and again in 1986, the Mexican government sponsored a Garbage Project study of the whole range of population in Mexico City. The goal in 1980 was to develop new data sources for the study of consumer behavior, with a special focus on food; in 1986 the data recording format added a special interest in household hazardous wastes. The 1980 study hand-sorted and recorded 1,085 pickups, which accounted for more than 10 tons of household refuse; the 1986 study hand-sorted and recorded 1,126 household pickups, which also accounted for more than 10 tons of refuse.

Census data and independent interviews were used to identify the socioeconomic characteristics of sampled neighborhoods. In addition, measures were taken to ensure that all refuse remained anonymous!

Mexico City sample neighborhoods stand in dramatic contrast to US sample neighborhoods in relation to material possessions. The economic conditions in the lowest-income neighborhoods, such as Las Trancas in the Azcapotzalco District of Mexico, are prime examples, as are the elite enclaves at the other end of the spectrum, such as Lomas de Chapultepec, which houses many of Mexico’s most important economic and political figures. While more than 90% of homes in all three Mexico City neighborhoods reported owning TVs, only 60% reported owning refrigerators in low-income neighborhoods. Very few US households in any sample areas lacked either a TV or a refrigerator. At the other end of the spectrum, food packaging and receipts tracked back to specific cash registers indicated that some Mexico City households did much of their weekly food shopping in stores in Houston, TX—that’s a long trek to pick up some Sugar Smacks!

In its analyses, the Garbage Project used “discriminant analysis” to compare Mexico City and US data. As part of the process, discriminant analysis examines refuse samples divided into groups and identifies those variables (called “key variables”) that differ significantly between sets. Mexico City income groups and US income groups were analyzed as separate sets. In each analysis, a number of food items were identified as key variables—27 for Mexico City and 20 for the US.

One way to understand the implications of these key variables is to divide them into “staple” foods and “preferential” foods. This is a somewhat subjective division. “Staples” are necessities, items with essential macro-nutrients or items necessary for food preparation. Animal and vegetable protein; basic cereal products; fruits and vegetables; juices; non-alcoholic, low-sugar beverages; and common baking additives are good examples. “Preferential” foods are expensive, exotic, non-essential commodities, including foods high in sugar, salt, and/or alcohol. The difference in staple and preferential key variables between Mexico City and US income groups is extremely distinctive.

In the United States, lower-income households consume larger quantities of staples, such as fresh vegetables, milk, and beans, while upper-income households consume larger quantities of preferential foods, such as oysters, hard liquor, and yogurt. In contrast, of the 27 variables identified for Mexico City, 25 were consumed at significantly higher rates by upper-income households. These include 15 staples, such as milk, corn, tortillas, and fresh fruit, as well as 10 preferential items, such as oysters, chips, and cocktail mix. Only two food items show a higher consumption in low-income households—candy and regular soda (oddly enough, two of the highest-cost items per ounce). Thus, this high-quantity consumption seems to separate upper- and lower-income consumers in Mexico City. There, upper-income consumers seem to be clear “super-consumers,” eating more “per person” of virtually everything.

Back to my original question: Does “super-consumption” really exist among the elite in Mexico City? I would have to say that the answer seems to be yes!

Garbage data clearly show evidence of significantly more food coming into households in upper-income neighborhoods. It is important to note that this includes both packaged items with contents marked in grams and debris from fresh produce. For example, upper-income household refuse shows evidence of 1.6 times more packaged foods than households in other neighborhoods. At the same time, interview data show significantly fewer people per upper-income household—even counting live-in and outside day workers. Finally, the rate of foodwaste in upper-income household refuse is identical to household refuse from other neighborhoods. Thus, upper-income consumers seem to be ingesting substantially more food per person—anywhere from 1.5 times the fat to 6 times the alcoholic beverages.

This was the mystery, until I recently unearthed a few references in the international health literature to studies that rely on interview-survey data rather than refuse. They indicate that elite super-consumption may be a pattern in rapidly industrializing urban areas. For example, in Hong Kong, Dr. Hill found in 1984 that the high-income subjects he interviewed “consumed more food of all types, including rice, cereals, green vegetables, fresh fruit, sugar, and meat.” This seems to be an accurate description of the upper income consumers in Mexico City as well. In another similar report, Dr. Haenszel and colleagues reported in 1975 that the upper-income residents of Cali, Columbia, were super-consumers, eating three to five times more of a wide variety of foods than lower-income populations.

While by no means a significant number of reports, these two studies, along with the Garbage Project results in Mexico City, suggest a possible pattern of super-consumption among elites in rapidly industrializing urban areas.

OK, now I could understand the theory, especially for a rapidly industrializing (meaning a processed- and fast-food–izing) country. You want to eat the comfort foods your mother brought you up with, but you also want to eat the new convenience foods that document your status and make your fast lane lifestyle workable. It would seem reasonable that they are replacing traditional eating behaviors with US-style consumption patterns. In actual practice, however, it would seem that elites are not abandoning their comfort foods. They are simply adding the new Western “status” foods (high fat, high protein, processed, and packaged commodities) on top of the old. As a result, the highest-income group—many of them nouveau riche and the most conspicuous of consumers—may regularly eat considerably more food per person than people in less economically advantaged groups.

Such exaggerated consumption has important implications for disease vectors. For decades, cancer researchers have documented that among laboratory animals, higher total food consumption—regardless of nutrient mix—leads to higher rates of cancer. In Hong Kong and in Cali, high income is associated with extremely high rates of large-bowel cancer, compared to such cancer rates in lower-income groups.

Thus, as much as elites in rapidly developing countries are seen as exploiters of the poor, at least in a statistical sense, capitalist bosses may be paying a price for their gluttony.

Archeologist and Contributing Editor W.L. Rathje is founder and director of the Garbage Project.

MSW - May/June 2005