Vegetables: from sweets to beets.

There is no such thing as a bad vegetable. (That is, not until food manufacturers turn some of them into potate chips, french fries, and receptacles for hollandaise or butter sauce.)

The food industry's dastardly tricks aside, some vegetables are better than others. Yet few people seem to know or care.

Many of America's favorite vegetables--like iceberg lettuce and celery--are among the least nutritious. And the unsung virtues of vegetables like collard greens and kale will probably remain so, because a new law will soon require nutrition labeling only on the 20 most popular vegetables. (Labeling of others will be optional.)

THE DUDS

The typical "salad," for example, combines some of the least nutritious vegetables. Its base is iceberg lettuce, now the second most popular American vegetable after potatoes. Eat a whole cup of iceberg and you get ten percent of the U.S. Recommended Daily Allowance (USRDA) for...well, nothing.

Likewise for salad vegetables like cucumbers, alfalfa sprouts, and raw mushrooms. Only tomatoes exceed ten percent of the USRDA for vitamin C--if you eat half a tomato.

Other popular vegetables are decidedly lackluster in the nutrient department. Celery sticks may be easy to hold, onions may add incomparable flavors, and beets may make borscht. But nutrients are not their forte. And green beans barely squeak by with some vitamin C.

True, there's nothing magic about the FDA's somewhat arbitrary rule that a food has to have at least ten percent of the USRDA to be a "significant source" of a nutrient. One cup of shredded iceberg lettuce, for instance, has eight percent of the USRDA for folate. So eat a cup-and-a-quarter and the level becomes "significant."

The point is not that putting iceberg lettuce in your salad is bad, but that spinach or romaine lettuce is much better.

THE POWERHOUSES

It's the beta-carotene that sends sweet potatoes and carrots to the top of the chart. Each has more than four times the USRDA. A sweet potato also supplies half the USRDA for vitamin C and an impressive 3.4 grams of fiber, even without its skin. (The government has no numbers for sweets with skin. Go figure.)

Then there are the dark leafy greens (or is it dark green leafies?). Spinach, collards, kale, dandelion greens, mustard greens, and Swiss chard are the decathletes of the vegetable kingdom.

Not only do they excel in vitamins A and C (no squeaking by here), but they offer some iron and calcium. (Sometimes the calcium in spinach is bound by oxalic acid, though, which means your body can't use it.)

LOST IN THE MIDDLE

Some of the middle-ranked vegetables are full of surprises.

Cooked mushrooms, for example, supply 20 percent of the USRDA for copper--a nutrient that's low in many diets. (Raw mushrooms have less, not because they acquire copper as they cook, but because half a cup of cooked mushrooms contains more mushrooms than half a cup of raw mushrooms.)

And parsnips, peas, corn, and artichokes each supply an impressive three grams of fiber. Kohlrabi has 74 percent of the USRDA for vitamin C. And okra just barely misses ten percent for vitamin A and folate (it's got at least ten for fiber and C, though).

So don't think you're wasting your time if you don't eat spinach or dandelion greens every day. The idea is to vary your vegetables and enjoy yourself.

SETTLING THE SCORE

To help you identify the best vegetables, we gave each one a score based on what percent of the USRDA it supplies for six nutrients plus fiber.

Our system isn't perfect, though. For example, it omits substances that are not conventional nutrients--things like the indoles and isothiocyanates in cruciferous vegetables like broccoli and cauliflower that might help prevent cancer. It ignores the still-unidentified components of garlic that might help lower cholesterol. Too little research has been done to warrant including these and other phyto-chemicals.

Another imperfection: some nutrients, like iron, are scarce in vegetables, while others, like vitamins A or C, are ample. So vitamin-A-rich vegetables like sweet potatoes and carrots get much higher scores than relatively iron-rich vegetables like potatoes or Swiss chard.

That was okay with us because vitamin A (which occurs in vegetables as beta-carotene), vitamin C, and folate are the nutrients most people need to get from vegetables (or fruit).

But that's why our chart has more than just the scores. The check marks tell you which vegetables give you a respectable dose of which nutrients. That way, if you don't eat many dairy products, for example, you can find the vegetables that are rich in calcium. Of if you don't eat red meat, you can find the vegetables that supply the most iron.

START COUNTING

The National Cancer Institute recommends that we eat at least five servings of fruits and vegetables each day, especially vegetables that are rich in vitamins A and C.

And don't complain that you can't "digest" vegetables or that your kinds won't eat them. Few people have trouble with carrots or potatoes.

So stop wasting time. I can smell those sweet potatoes baking already.