Lettuce

Lettuce: Nutrition Facts and Health Benefits

Lettuce (Lactuca sativa) is one of the most widely grown and consumed salad vegetables in the world, cultivated since ancient Egyptian times and now consumed globally in countless varieties. The four main types are crisphead (including iceberg), butterhead (including Boston and Bibb), romaine (cos), and loose-leaf varieties. Each has a distinct texture, flavour, and nutritional profile, with darker-leaved varieties generally offering more nutrients. Lettuce is among the most water-rich vegetables, with a very mild flavour that makes it a versatile base for salads and wraps.

Nutritional Value of Lettuce

Lettuce is exceptionally low in calories — 17 kcal per 100 g — and very high in water content, typically around 95%. It provides 2.1 g of dietary fibre per 100 g. The nutritional content varies considerably between varieties: romaine and dark leaf lettuces are significantly richer in vitamins A (as beta-carotene), C, and K than iceberg lettuce. Folate is present across all varieties and is a notable nutrient in romaine. Potassium, calcium, magnesium, and phosphorus are present in small but meaningful amounts. Romaine lettuce contains useful amounts of lutein and zeaxanthin, carotenoids associated with eye health.

Health Benefits of Lettuce

Lettuce's very low calorie and high water content make it an excellent food for meals that provide volume and satisfaction with minimal caloric contribution. Darker varieties provide vitamin K for bone health and blood clotting, and beta-carotene for immune function and eye health. Folate is important for cell division and DNA synthesis. The fibre in lettuce supports digestive health. Lettuce contains lactucarium, a milky substance that has historically been associated with mild sedative properties, though dietary quantities are unlikely to produce pharmacological effects.

How to Select and Store Lettuce

Choose lettuce with firm, bright green (or red for red varieties) leaves without browning edges, wilting, or sliminess. Loose-leaf varieties are more perishable than tight heads. Store unwashed in a plastic bag or container in the refrigerator crisper for three to seven days depending on variety — iceberg keeps longer than loose-leaf types. Wash just before use, as excess moisture accelerates deterioration.

How to Use Lettuce

Lettuce is most commonly used raw in salads, sandwiches, and wraps. Romaine and butterhead leaves are sturdy enough to use as edible cups or wraps for fillings. Iceberg holds up well as a base for wedge salads. Romaine is the classic choice for Caesar salad. Lettuces can also be briefly wilted into stir-fries, soups, and braised dishes, particularly in Chinese and French cuisine where braised lettuce is a traditional side dish.