Lettuce is a versatile food, but most associate it with salads or a health-conscious substitute for bread. Americans ate nearly 26 pounds of lettuce in 2015, according to the Agricultural Marketing Research Center, a number that was down about 20% from the previous decade.
We brought you the healthiest salad dressing recommended by dietitians and the healthiest vegetables to put in salads, but what about the healthiest lettuce? Here’s what to know about the nutritional content of your base.
What is the healthiest lettuce?
There are several different kinds of lettuce, mostly differing in shape and in taste. While all lettuce is going to provide you with healthy vitamins and minerals, romaine lettuce is the most nutrient-dense, says registered dietitian Danielle Crumble Smith.
“It’s going to have the highest amount of vitamin A, K, C,” she says. “Romaine lettuce also has a little bit of potassium, a little bit of iron, a little bit of molybdenum, a little bit of fiber.”
Vitamin A supports eye health and promotes cell growth and activity. Vitamin C acts as an antioxidant and helps form blood vessels, cartilage, muscle and collagen in the bones. It also helps absorb and store iron. Vitamin K is a fat-soluble vitamin (making lettuce and salad dressing the perfect pair) that helps blood clot normally and plays a role in bone health.
Romaine also contains folate, which is recommended during pregnancy because of its role in DNA and RNA formation, but it’s important for everyone. The benefits of folate include improved digestive system functioning and preventing common cancers, cardiovascular disease, infertility, stroke, dementia and Alzheimer’s disease.
Other healthy winners are red and green leaf lettuce, Crumble Smith says. Red and green leaf lettuce have the same vitamins and nutrients as romaine and are also good sources of anthocyanins, an antioxidant found in fruits and vegetables that are dark red or purple. Antioxidants combat free radicals, which are unstable and highly reactive molecules that can lead to cellular aging, damage and cause disease. Anthocyanin in particular may help lower blood pressure, heart disease risk, neurological disease risk and slow cancer growth.
“That’s a good way to help bolster your body’s immune system … if you can consume a wide array of different types of antioxidants,” Crumble Smith says.
Butterhead lettuce, which some call Bibb or Boston lettuce, is another nutrient-dense option that’s packed with vitamins A, C, K, folate, iron and fiber.
But getting a variety of lettuce and greens is more important than stressing about one particular “healthier” type, Crumble Smith says. Take iceberg lettuce, for example. The popular crispy green is perhaps the least nutrient-dense because it’s 96% water, but it would still give you some amounts of vitamins A, C and K.
“Truthfully, they’re pretty much going to have similar nutrient profiles.” Crumble Smith says. “The darker the color, the higher concentration of antioxidants that you’re going to get.”
Dietary fiber: Why it’s important and what to eat to get more
Is lettuce good for you?
Yes, lettuce is a good source of vitamins A, C, K as well as hydration.
“We sometimes discount the water that we can actually get from the foods that we eat,” Crumble Smith. “That does not mean that you could just eat a bunch of lettuce and not drink water, but know that it can have hydrating benefits.”
Experts previously told USA TODAY about a third to a half of adults’ 100-ounce per day recommendation should come from plain water, not food.
More than just lettuce, greens are a good way to up your daily vegetable intake, which only one in 10 Americans consume enough of.
“Try to consume things of different colors,” Crumble Smith recommends, in terms of buying greens. Cruciferous vegetables like cabbage contain fiber and have natural detoxification benefits for the body. They also pair well with lettuce. “People are often like ‘How can I cleanse?’ but eating real food is a great way to do that.”
What are greens?
Greens are types of vegetables that include lettuce, arugula, spinach, cabbage, kale, bok choy and more. They are healthy sources of vitamins and nutrients that protect us from heart disease, stroke and cancer, the Centers for Disease Control and Prevention says.
Lettuce is often the star of the show in salads and wraps, but Crumble Smith recommends adding some of these healthy greens alongside it:
- Arugula: Good source of vitamins A, C, K, calcium and potassium
- Watercress: Good source of vitamins A, C, K, calcium, magnesium and glucosinolate, which is anti-inflammatory and may decrease risk of certain diseases and cancers
- Endives and radicchio (often served at restaurants): Good sources of vitamin E, C and K; beta carotene, which converts into vitamin A; flavonoids, which act as antioxidants; and inulin, a prebiotic fiber that helps beneficial gut bacteria grow
- Other cruciferous vegetables: Good source of vitamins A, C, K and phytonutrients and include kale, bok choy, collard greens, mustard greens and cabbage
Spinach is another healthy source of vitamin C in its raw form (it’s reduced when you cook it). Raw spinach does contain oxalates, which reduce the absorption of calcium and iron, so Crumble Smith warns those who are calcium- or iron-deficient should get those vitamins from meals that don’t contain spinach.
Crumble Smith also recommends getting in the greens from other produce – the parts of carrots, beets and other vegetables that you typically throw away can be washed, chopped and added to salads or dishes.
Many of these healthy greens are on the “Dirty Dozen” list, or the Environmental Working Group’s analysis of the 12 vegetables with the highest traces of pesticides. In 2023, that’s spinach, kale, collard and mustard greens.
This doesn’t mean you shouldn’t eat these greens, Crumble Smith says. Buying organic is one option if you’re eating any of them daily. Still, organic produce is not completely pesticide-free because farmers often use naturally-derived pesticides derived. Research published in the Journal of Toxicology found the pesticides in the produce on the “Dirty Dozen” list are “at negligible levels” and substituting organic didn’t result in significant risk reduction.
“If getting organic versions of those is too expensive, eat the vegetable. You’re still getting benefits,” Crumble Smith says.
Contaminated leafy greens can also cause illness, so the CDC recommends thoroughly washing greens or buying ones labeled as “ready to eat,” “triple washed” or “no washing necessary.”
Is lettuce a vegetable?
Yes, lettuce is included in the leafy greens portion of the vegetable group.
The Dietary Guidelines for Americans recommend 2 ½ cups of vegetables per day based on a 2,000-calorie diet. About 1 ½ cups of those should be dark green vegetables.
If you’re sick of salads and struggling to get leafy greens in, here are some recommendations from Crumble Smith to try:
- Put them in a sandwich or wrap
- Experiment with texture – chop or shred finely
- Pair them with other nutrient-dense ingredients like rice, beans or meat
- Blend it in a food processor and add it to meatballs, burger patties or meatloaf
- Add them to smoothies
- Blend them with muffin mix and mask the taste with chocolate
Discover more health tips for your daily diet:
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