Quotulatiousness

October 3, 2015

“A head of iceberg lettuce has the same water content as a bottle of Evian”

Filed under: Food, Health, Science — Nicholas @ 03:00

Another older article that I neglected to blog when it was still fresh and green on the … shelf. Here’s a few less-than-appetizing facts about salad vegetables:

Salad vegetables are pitifully low in nutrition. The biggest thing wrong with salads is lettuce, and the biggest thing wrong with lettuce is that it’s a leafy-green waste of resources.

In July, when I wrote a piece defending corn on the calories-per-acre metric, a number of people wrote to tell me I was ignoring nutrition. Which I was. Not because nutrition isn’t important, but because we get all the nutrition we need in a fraction of our recommended daily calories, and filling in the rest of the day’s food is a job for crops like corn. But if you think nutrition is the most important metric, don’t direct your ire at corn. Turn instead to lettuce.

One of the people I heard from about nutrition is researcher Charles Benbrook. He and colleague Donald Davis developed a nutrient quality index — a way to rate foods based on how much of 27 nutrients they contain. Four of the five lowest-ranking vegetables (by serving size) are salad ingredients: cucumbers, radishes, iceberg lettuce and celery. (The fifth is eggplant.)

Those foods’ nutritional profile can be partly explained by one simple fact: They’re almost all water. Although water figures prominently in just about every vegetable (the sweet potato, one of the least watery, is 77 percent), those four salad vegetables top the list at 95 to 97 percent water. A head of iceberg lettuce has the same water content as a bottle of Evian (1-liter size: 96 percent water, 4 percent bottle) and is only marginally more nutritious.

Take collard greens. They are 90 percent water, which still sounds like a lot. But it means that, compared with lettuce, every pound of collard greens contains about twice as much stuff that isn’t water, which, of course, is where the nutrition lives. But you’re also likely to eat much more of them, because you cook them. A large serving of lettuce feels like a bona fide vegetable, but when you saute it (not that I’m recommending that), you’ll see that two cups of romaine cooks down to a bite or two.

The corollary to the nutrition problem is the expense problem. The makings of a green salad — say, a head of lettuce, a cucumber and a bunch of radishes — cost about $3 at my supermarket. For that, I could buy more than two pounds of broccoli, sweet potatoes or just about any frozen vegetable going, any of which would make for a much more nutritious side dish to my roast chicken.

Lettuce is a vehicle to transport refrigerated water from farm to table. When we switch to vegetables that are twice as nutritious — like those collards or tomatoes or green beans — not only do we free up half the acres now growing lettuce, we cut back on the fossil fuels and other resources needed for transport and storage.

Save the planet, skip the salad.

No Comments

No comments yet.

RSS feed for comments on this post.

Sorry, the comment form is closed at this time.

Powered by WordPress