How nutritious is iceberg lettuce?
Of all lettuces, this pale green variety (also called head lettuce) is the least nutritious, providing only very small amounts of vitamins, minerals, and fiber. On the positive side, like all lettuces, iceberg is low in calories (12 per 3 ounces)—and its high water content may help fill you up, so if you eat a salad before a meal, you might eat fewer calories overall. In addition, iceberg lettuce is cheaper and stays fresher longer than many other lettuces.
But if you're looking for more nutritional lettuce for your buck—and more flavor—darker-colored salad greens are a much better choice. Romaine, spinach, butterhead, and arugula, for example—along with the less familiar mizuna, mache (lamb's lettuce), and tat soi—offer more vitamin C and K, folate, magnesium, and other nutrients and about twice as much fiber. And they're richer in beta carotene, lutein, zeaxanthin, and other potentially beneficial compounds.
You can't go wrong eating any kind of lettuce, but the best advice is to choose a more colorful variety.
Source: Originally published in The University of California, Berkeley Wellness Letter (March 2011)