Some time ago, Michael Ruhlman lent me a book by Chef Dan Barber called The Third Plate: Field Notes on the Future of Food. It took me a long time to get through the book, primarily because it made me think so hard that I could read barely one chapter at a time. In 2009, the same year I started writing Your Health is on Your Plate, TIME Magazine named Dan Barber as one of the 100 most influential people in the world.

Third Plate got me thinking about the fact that mainstream America survives not on nutritious food but, instead, on a commodity-based diet. When goods and services are traded on the grand scale for other goods and services, they become commodities. The primary characteristic of a commodity is that its price is determined not by quality but, rather, quantity. A commodity meets explicit contractual requirements unrelated to the product’s nutritive value or taste, so that the source and nutritional quality of the product become, essentially, irrelevant. Commodities from different producers are of more-or-less uniform quality and, therefore, considered equivalent. Food-based commodities include white flour, sugar, soybean oil, degerminated corn meal, corn syrup, and corn starch. Other kinds of commodities include coal, gold, silver, iron ore, and aluminum.

We grow commodities, eat them, export them and feed them to animals. We modify them to reduce their nutritional value, and use words like “enriched” or “fortified” when anemia (iron), beri-beri (thiamine), and spina bifida (folate) lead to Congressionally-mandated replacement of nutrients whose removal caused those epidemics. The short cuts created by commodity-based eating have also manifested in a worldwide epidemic of a different sort of malnutrition than seen before, the most visible symptom of which is obesity.

This is a major frameshift in how to think about food. Ask yourself if your meal is nourishing or entertaining. If you aren’t sure, consider the possibility that even though it is edible, it may not be food. Michael Pollan calls these items “food-like.” That doesn’t mean you should never eat them. It means they don’t go in the plus category.

The opposite of commodity is “terroir,” a concept that describes a food so profoundly influenced by its origin that its location is an integral part of its identity. Words like terroir [French], territory and terrain [English] and tierra [Spanish] derive from the Latin terra, or earth. Components of terroir include climate, soil type, elevation, landscape, and even other plants growing nearby. The food grown here simply could not come from anywhere else. Terroir is about quality-over-quantity; it cannot be duplicated.

The identities of heirloom tomatoes, heritage wheat, chocolate, cognac, champagne, oolong tea, Iberian ham, hops and Parmigiana cheese are linked intimately to their places of origin. An attempt to grow or create the identical product elsewhere could never be successful. It’s about the angle of the sun, the direction of the rain, characteristics of the soil, the oak that grows there, and the acorns it produces to feed the pigs or geese who live in that one corner of Earth.

Terroir is a joy, an occasion, a memory. It would be unusual for most people to have access to this kind of quality on a daily basis. But the concept does help to explain why commodities are less likely to be a quality product. How could they be?

To the extent that you can decrease the quantity of commodities you eat—as ultra processed wheat, soy, corn and rice—and replace them with food for which quality is a higher priority, you can expect to reap the benefits.