Which Is Healthier, Romaine or Iceberg Lettuce?

Everyone's familiar with lettuce. From its use in salads to its presence in sandwiches, this plant is an often-seen part of many everyday foods. Romaine lettuce and iceberg lettuce are two of the most common types of vegetables used in salad. They offer similar nutrients, and because both have crunchy leaves and similar uses, they can be hard to tell apart.

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The difference between romaine and iceberg lettuce can be confusing, given that these are both low-calorie salad vegetables used in the same sorts of dishes. The easiest way to differentiate these two types of lettuce is based on their shape. Romaine lettuce is longer, greener and leafier in appearance. It's often used in Caesar salads, but you may find it used in many other dishes too. Romaine lettuce is also quite sturdy. If you're on a low-carbohydrate diet and can't eat bread, romaine lettuce is sturdy enough to act as the carrier for your dip or sandwich filling.

In contrast, iceberg lettuce is crunchy and pale and grows into a round shape resembling a ball. On its own, it's almost flavorless. However, this makes it a great crunchy salad vegetable that carries the flavor of any dressing or other ingredients used in the dish. You'll find iceberg lettuce frequently used in chicken and tuna salad or inside burritos and hamburgers. According to the U.S. Food and Drug Administration, the serving size for both of these types of lettuce is between 85 to 90 grams.

There are quite a few different types of iceberg lettuce, such as equinos, ice castle and metalia. A full head can range anywhere from 485 to 800 grams in size, which means you may get anywhere from 5 to 10 servings of iceberg lettuce per head. This type of lettuce is the most popular in the United States.

One serving of iceberg lettuce, which is equal to 1 cup, has only 13 calories. Iceberg lettuce is rich in:

• vitamin A (9 percent of your recommended daily value)
  
• folate (6 percent of your recommended daily value)
  
• vitamin K (27 percent of your recommended daily value)
  
• manganese (6 percent of your recommended daily value)
  

Each serving contains small amounts of fiber, protein and nutrients like B-complex vitamins and vitamins C and E. Low amounts (between 1 to 4 percent) of many minerals, including calcium, copper, iron, magnesium, phosphorus, potassium and zinc are also present in each serving.

Romaine lettuce nutrition is generally considered to be better than that of iceberg lettuce when comparing equivalent serving sizes. Each serving of romaine lettuce has 15 calories. In terms of vitamins and minerals it contains:

• Fiber (7 percent of your daily recommended value)
  
• Folate (29 percent of your daily recommended value)
  
• Iron (5 percent of your daily recommended value)
  
• Potassium (6 percent of your daily recommended value)
  
• Manganese (7 percent of your daily recommended value)
  
• Vitamin A (148 percent of your daily recommended value)
  
• Vitamin C (34 percent of your daily recommended value)
  
• Vitamin K (109 percent of your daily recommended value)

It also has small amounts (between 1 to 4 percent) of protein, calcium, copper, magnesium, phosphorus, several B-complex vitamins, vitamin E and zinc.

As you can see, iceberg lettuce and romaine lettuce have similar nutrients, but romaine lettuce has substantially more of these vitamins and minerals. If you're choosing between these two types based on nutritional values, there's no contest — romaine is the winner. This comparison is less clear between other types of lettuce, though. When it comes to butter lettuce vs. romaine, butter lettuce has less vitamin A and vitamin C, but more vitamin K, iron and manganese.

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