"...not talking about the small but significant decline in nutrient density since the industrialization of agriculture half a century ago, but rather a steep drop in phytonutrients that began when we "stopped foraging for wild plants some 10,000 years ago and became farmers." Robinson writes:
Each fruit and vegetable in our stores has a unique history of nutrient loss, I've discovered, but there are two common themes. Throughout the ages, our farming ancestors have chosen the least bitter plants to grow in their gardens. It is now known that many of the most beneficial phytonutrients have a bitter, sour or astringent taste. Second, early farmers favored plants that were relatively low in fiber and high in sugar, starch and oil. These energy-dense plants were pleasurable to eat and provided the calories needed to fuel a strenuous lifestyle. The more palatable our fruits and vegetables became, however, the less advantageous they were for our health.
I would push back against the inverse relationship Robinson posits between palatability and nutrition. I imagine that we've lost a lot of flavor in the ages-old quest to breed for sweetness—and in the last 100 years or so, we've definitely lost still more by breeding for portability and shelf life. I would argue that flavor has declined along with nutrient density. Few people would choose modern supermarket tomatoes bred to last for weeks post-harvest over old varieties selected to taste good when eaten quickly. And weeds play a role in some of the globe's most celebrated cuisines. I wouldn't want to imagine Mexico's street food without tlacoyos con quelites (lamb's quarters) or Italy without ravioli d'ortica (stinging nettles). There's no puritanical trade-off here. (Patience Gray's classic Honey from a Weed demonstrates how vital weeds remain in southern European cooking, and Rebecca Katz and Mat Edelson's recent The Longevity Kitchen offers plenty of good recipes for them).
What we can do is start seeking out varieties of fruits and vegetables that haven't been bred to be insipidly sweet.
That caveat aside, what do we do with Robinson's message about the loss of phytonutrients? Obviously, we can't all suddenly become hunter-gatherers, stalking city parks for hidden bounty (though a fellow who calls himself "Wildman" will take you on a foraging tour of Manhattan's Central Park). Nor can we all live on small organic farms surrounded by woodlands.
But what we can do is start seeking out varieties of fruits and vegetables that haven't been bred to be insipidly sweet or high-yielding. Robinson suggests arugula as an example—it was a Mediterranean weed until very recently. Arugula is "very similar to its wild ancestor," she notes, and "rich in cancer-fighting compounds called glucosinolates and higher in antioxidant activity than many green lettuces." Robinson also points to herbs, which she calls "wild plants incognito." That is, they much more closely resemble their wild antecedents than do, say, modern apples or tomatoes or corn. She adds: "We've long valued them for their intense flavors and aroma, which is why they've not been given a flavor makeover. Because we've left them well enough alone, their phytonutrient content has remained intact."
