Health Benefits of Lettuce

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Medically reviewed by Barbie Cervoni, RD

Lettuce (Lactuca sativa L.) is a popular vegetable that’s a staple in many people’s diets. There are seven main types of lettuce, including cos or romaine, butterhead, leaf, stalk, crisphead, latin, and oilseed.

Though lettuces vary in color, taste, and nutritional value, most types are packed with vitamins, minerals, and other protective substances. For example, eating more lettuce can help boost your intake of essential nutrients, such as folate and vitamin C, as well as plant compounds like carotenoids, all of which can help support overall health and reduce the risk of common health conditions, such as heart disease.

Here’s everything you need to know about the health benefits of lettuce and how to incorporate it into your diet.

Provides Essential Nutrients

Lettuces, like romaine and butterhead lettuce, are a good source of certain essential nutrients, such as folate and vitamin A.

Folate is a B vitamin that’s required for a number of critical processes in the body, such as red blood cell development and cellular division. This B vitamin is in high demand during pregnancy, as it’s required for fetal growth and development.

During pregnancy, folate needs increase by 50%, which is why increasing your intake of folate-rich foods, like lettuce, and taking supplemental folate or folic acid is so important. A one-cup serving of romaine contains 63.9 micrograms (mcg) of folate, which covers 16% and 11% of folate needs for non-pregnant and pregnant people, respectively. This makes romaine and other folate-rich lettuces a good choice for boosting folate intake.

Lettuce is also high in vitamin A, which plays important roles in growth and development, cellular communication, immune function, and other critical processes.

Like folate, pregnant people require extra vitamin A to support fetal growth and their own health during pregnancy and throughout breastfeeding. A one-cup serving of romaine provides 205 micrograms of vitamin A, which covers 23% of the DV for vitamin A, which is set at 900 mcg.

Vitamin K is another nutrient that’s found in high amounts in lettuce. Getting enough vitamin K is important for the health of your bones and is required for blood clotting.

In addition to folate, Vitamin A, and vitamin K, lettuce contains smaller amounts of other vitamins and minerals, such as vitamin C and potassium, making it a nutritious choice.

A Good Source of Protective Plant Compounds

Lettuce is packed with plant compounds such as carotenoids, phenolic acids, and flavonoids, all of which have powerful cellular-protective properties.

For example, lettuce is high in the carotenoids beta-carotene and lutein, which have antioxidant effects in the body. Antioxidants protect against cellular damage by neutralizing highly reactive compounds called free radicals. Free radicals are byproducts of metabolism and other processes. When free radicals overwhelms the body’s antioxidant defenses, it leads to a condition called oxidative stress, which triggers damage to your cells and chronic inflammation. Oxidative stress accelerates the aging process and is associated with a number of diseases, including heart disease and certain cancers.

Eating antioxidant-rich foods like lettuce can help support your body’s antioxidant defenses and protect against oxidative stress, thus reducing your risk of common health conditions, For example, studies show that people who consume diets rich in antioxidants found in lettuce, such as β-carotene and polyphenols, have a lower risk of developing certain cancers.

A 2024 review of 15 studies found that people with the highest circulating blood levels of carotenoids had a 24% reduced risk of developing breast cancer compared to those with the lowest circulating levels.

Higher blood levels of carotenoids like β-carotene and lutein, which are concentrated in lettuce, have also been shown to protect against heart disease and age-related macular degeneration (ARMD), an eye disease that’s currently the leading cause of vision loss in older people.

Lettuces also provide polyphenol compounds, such as caffeic acid, kaempferol, and quercetin. Studies show that polyphenols protect against common health conditions like neurodegenerative disease, heart disease, and stroke by supporting blood vessel health, reducing inflammation, and regulating blood lipid levels.

May Reduce Disease Risk and Support Mental Health

Adding more vegetables to your diet is one of the best ways to look after your health and lower your risk of developing chronic health conditions.

Decades of research findings have shown that people who consume more vegetables, especially raw vegetables like lettuce, tend to have lower rates of diseases like cancer, type 2 diabetes, and heart disease. This is because vegetables, like lettuce, are low in calories yet high in protective plant compounds, vitamins, and minerals.

Incorporating more vegetables into your diet can help boost your nutritional intake and increase your consumption of compounds that help protect cells from oxidative damage, support healthy blood sugar and blood lipid levels, and reduce inflammation.

Eating more raw vegetables may also improve your mental health and protect against depressive symptoms. A 2018 study that included 422 people found that those who consumed more raw vegetables and fruit had lower rates of depressive symptoms and had higher positive mood and life satisfaction compared to those who ate more cooked and canned fruits and vegetables. The researchers reported that lettuce was amongst the top ten raw foods linked to better mental health outcomes in this population.

Nutritional Facts of Lettuce

The nutrition of lettuce varies, but most lettuces are a good source of vitamins and minerals.

Here’s the nutrition breakdown for a one-cup serving of shredded romaine lettuce:

• Calories: 7.99
• Fat: 0.15 grams (g)
• Carbohydrates: 1.55 g
• Fiber: 0.98 g
• Protein: 0.57 g
• Vitamin A: 205 micrograms (mcg) or 23% of the Daily Value (DV)
• Vitamin K: 47.9 mcg or 40% of the DV
• Folate: 63.9 mcg or 16% of the DV

Water makes up between 94% to 95% of lettuce’s weight, making it a particularly hydrating food. Because it’s so rich in water, lettuce is very low in calories, containing fewer than 10 calories per cup.

Lettuce, like romaine, is a rich source of vitamins A, K, and folate. It also provides smaller amounts of fiber, which is important for digestive health, plus other vitamins and minerals, including potassium, iron, and vitamin C.

Risks of Eating Lettuce

Lettuce is safe for most people to enjoy and is not associated with many health risks. Lettuce allergy is uncommon. However, people with a condition called lipid transfer protein (LTP) sensitization, a type of food allergy in which people react to certain proteins found in a variety of plant foods, may experience mild to severe allergy symptoms after eating lettuce.

Additionally, lettuce can be contaminated with harmful bacteria that cause foodborne illness, such as E. coli, norovirus, Listeria, Salmonella, and Cyclospora.

Because of this contamination risk, it’s important to thoroughly rinse lettuce under running water before consuming it. Other ways to prevent bacterial contamination of lettuce include:

• Keeping lettuce away from raw meat, poultry, and seafood and using separate cutting boards for raw vegetables.
• Storing lettuce in the refrigerator set to 40°F or colder in a clean container.
• Washing and sanitizing cutting boards, utensils, and kitchen surfaces before preparing lettuce.
• Refrigerating lettuce and salads within two hours of preparation.

Using these food safety techniques can minimize your risk of getting sick from a foodborne illness.

Tips for Consuming Lettuce

Lettuce is popularly consumed in salads, but can be added to a number of other dishes to boost texture, taste, and nutritional value.

Here are a few ways to enjoy lettuce:

• Make a nutrient-dense salad by combining raw lettuce with other vegetables, like carrots, peppers, and cucumbers.
• Add fresh lettuce to sandwiches, tacos, and burritos.
• Stuff lettuce leaves with cooked ground chicken and vegetables for a low-carb meal idea.
• Use lettuces like romaine to make homemade green juices and smoothies.
• Grill lettuce and top it with cheese and seeds or nuts for a unique twist on salad.
• Add fresh lettuce to rice and noodle bowls for a crunchy texture and refreshing taste.

Remember, there are multiple kinds of lettuce to choose from, some of which may work better in certain dishes than others. For example, romaine has a crunchier and stiffer texture that can stand up to grilling, while butterhead lettuce has a soft texture and buttery taste that works well in salads and other raw dishes.

A Quick Review

Lettuce is a leafy vegetable that’s commonly enjoyed in dishes like salads and sandwiches. There are many kinds of lettuce, most of which are highly nutritious.

Lettuce is a good source of several nutrients, such as vitamin A and folate, and also provides a number of protective plant compounds that can boost health in several ways.

Adding more lettuce to your diet can help protect your health and may lower your risk of developing common conditions, such as certain cancers and heart disease.

Plus, lettuce is delicious and can add color, texture, flavor, and nutritional value to your favorite dishes.

Read the original article on Health.com.