A caveat up front: this one depends entirely upon the season, and even the year.  A few years back we had a bad season for lettuce, which drove prices up to almost $5 a head for some of the fancier varieties.  

Why buy an entire head of lettuce?  You might be tempted to buy a bag of pre-cut lettuce.  After all, it saves time, and you don't have to pick out the lettuce type.  Sometimes it's easier to just grab the bag.

But if you actually weigh out a head of lettuce versus a bag, the bagged stuff costs at least three times more.  The last time I was at the store, they were selling an 8 ounce bag of pre-cut lettuce for $3.49, while I could buy an entire head of red leaf lettuce for $1.99.  The head of lettuce weighed almost a pound, which put it at 12 cents per ounce.  Whereas the pre-cut stuff cost 43 cents per ounce.  That's a pretty big jump!

The pre-cut stuff is also, in my experience, completely bland and tasteless.  It has crunch, but little else.  A proper head of lettuce has far more to offer the senses.  And I like to think it has more nutrients, but that could just be my lettuce prejudice showing through.  Red leaf lettuce is best, followed by green leaf lettuce, and romaine lettuce.  Iceberg lettuce is tasty, although not particularly nutritious.

Most lettuce is washed fairly well before it gets to the store.  Preparation consists of ripping off a few leaves, running them under a cold tap, and shaking off the excess water.  You can pat them dry with a towel, but I never bother.

One head of lettuce will make at least two really big meal-size salads, or four substantial side salads. That's a pretty good deal!  Leaf lettuce has a lot of micronutrients like vitamins A and K, beta carotene, and lutein.  But I think the real health benefit to buying a head of lettuce is that it serves as a place setting for a lot of other nutritious stuff, too.

Salads are a great way to use a variety of fresh vegetables.  You can eat just about anything in a salad, which gives you the flexibility to buy whatever vegetables are on sale.  Radishes and carrots are usually cheap, and give a great nutritional boost.  (I like to grate carrots on a cheese grater to make shreddies.)  Sprouts, tomatoes, cucumbers, snap peas… the list of possibilities is pretty much endless.

I like to add some protein to my salads, to make them more filling.  I toss on a handful of grated cheese, or crumble up a hard boiled egg.  You can also add deli meats sliced into small chunks.  This is a great way to use up those last little bits of leftover meat.

As for salad dressing, it's easy and healthier to make your own for a fraction of the cost!  Pour about four parts olive oil to one part vinegar (red wine or balsamic) into a bowl.  Add a few dashes of salt and pepper to taste.  Whisk together with either a dab of Dijon mustard, or a crushed clove of garlic, or both.

Creative Commons-licensed image courtesy of Flickr user Natalie Maynor