Calories in Lettuce

Updated July 2026 · Reviewed by CaloriesCalc Team · Source: USDA FoodData Central

15
kcal
per 100g
2.87
g
Carbs
1.36
g
Protein
0.22
g
Fat
1.3
g
Fiber
11
kcal per cup shredded (72g)
21
kcal per head romaine (141g)
4
kcal per oz (28g)
✔ Extremely low calorie✔ 96% water✔ Good vitamin K✔ Fat free✔ Gluten free✔ Vegan
Lettuce nutrition facts and calories per 100g
🔥Only 15 kcal per 100g — near zero calories
💧96% water content
🦴Good vitamin K — 102µg per 100g romaine
😌Keto friendly — 1.6g net carbs
😴Contains lactucin — mild sedative
🥗Base of virtually every diet salad

🥬 Calculate Calories for Any Lettuce Weight

Weight100g

Nutrition Facts

Per 100g (raw lettuce)

* % Daily Value based on a 2,000 kcal diet.


Quick summary: Lettuce contains just 15 calories per 100g and 11 calories per cup. Romaine lettuce provides 85% of daily vitamin K and 48% of vitamin A per 100g — far superior to iceberg lettuce which is mostly water. With only 1.6g of net carbs, lettuce is fully keto-compatible. It contains lactucin — a mild sedative compound that may support sleep.

Vitamins & Minerals — per 100g

NutrientAmount% Daily ValueBar
Vitamin K102.5 µg85%
Vitamin A (RAE)436 µg48%
Folate (B9)136 µg34%
Vitamin C9.2 mg10%
Potassium194 mg4%
Vitamin B60.09 mg5%
Magnesium13 mg3%
Calcium33 mg3%
Phosphorus30 mg2%
Iron0.97 mg5%

Calories in Lettuce by Weight

WeightCaloriesCarbsProteinFat

Calories in Different Lettuce Servings

ServingWeightCaloriesCarbsNet CarbsFat
⭐ 1 cup shredded72g11 kcal2.1g1.1g0.2g
1 large leaf28g4 kcal0.8g0.4g0.1g
1 head romaine141g21 kcal4.1g2.3g0.3g
1 head iceberg539g81 kcal15.5g8.7g1.2g
1 oz28g4 kcal0.8g0.4g0.1g
How does lettuce fit your daily calorie goal?
Calculate your TDEE to see exactly how it fits your daily budget
Calculate TDEE →

Macronutrient Breakdown — per 100g

Carbohydrates2.87g · 69% of calories
Protein1.36g · 36% of calories
Fat0.22g · 13% of calories
Fiber1.3g (included in carbs)

Romaine lettuce is 95% water. Net carbs are 1.6g per 100g — one of the lowest of any food. Different varieties vary significantly: romaine and red leaf lettuce are far more nutritious than iceberg lettuce.

Micronutrient Highlights

🦴
Vitamin K
102.5 µg
85% Daily Value
Blood clotting and bone health (romaine)
👁
Vitamin A (RAE)
436 µg
48% Daily Value
Vision and immune function (romaine)
Potassium
194 mg
4% Daily Value
Blood pressure support
🛡
Vitamin C
9.2 mg
10% Daily Value
Immune support
🌿
Folate (B9)
136 µg
34% Daily Value
Cell division and DNA synthesis
😴
Lactucin
Trace
Phytochemical
Mild sedative and pain-relieving properties

Lettuce Health Benefits & Nutrition

Romaine vs Iceberg — A Significant Difference

Not all lettuce is equal. Romaine lettuce is dramatically more nutritious than iceberg: it contains 8× more vitamin A, 4× more vitamin K, 3× more vitamin C, and 2× more folate and iron. Iceberg lettuce is 96% water with minimal nutrients — essentially crunchy water. For maximum nutritional benefit, choose romaine, red leaf, green leaf, or butterhead lettuce over iceberg. The darker the green, the more nutrients.

Lactucin — The Sedative Compound

Wild lettuce has been used as a sedative for centuries. Cultivated lettuce still contains small amounts of lactucin and lactucopicrin — bitter compounds with mild sedative and analgesic (pain-relieving) properties. A 2017 study found lettuce extract had significant sedative effects in mice, reducing movement by 30%. While the amounts in a salad are small, some people report that large amounts of lettuce (particularly romaine) cause drowsiness — this is attributed to lactucin.

Vitamin K for Bone Health

Romaine lettuce provides 103µg of vitamin K per 100g — 85% of the daily requirement. Vitamin K1 activates osteocalcin, which binds calcium into bone matrix, and also activates matrix Gla-protein (MGP), which prevents calcium from depositing in blood vessels (arterial calcification). Low vitamin K intake is independently associated with osteoporosis and cardiovascular disease. Dark leafy lettuces are among the best dietary sources of this underconsumed vitamin.

Ultra-Low Calorie for Weight Management

At 15 kcal per 100g, lettuce is one of the lowest-calorie foods available. A large salad bowl (200g of romaine) has only 30 calories. The high water and fiber content creates gastric volume and triggers satiety signals before significant calories are consumed. Studies on high-volume, low-calorie eating (volumetrics approach) consistently show that starting meals with large salads reduces overall calorie intake by 100-200 kcal.

Is Lettuce Suitable for Your Diet?

Weight loss
Excellent — 15 kcal, near zero
Keto
Yes — 1.6g net carbs
Vegan
Yes
Paleo
Yes
Gluten-free
Yes
Diabetic
Yes — GI ~15
Low-FODMAP
Yes
Mediterranean
Core ingredient

Frequently Asked Questions

How many calories in lettuce?
Lettuce contains 15 calories per 100g. A cup of shredded romaine (72g) has 11 calories. A whole romaine head (141g) has 21 calories. A whole iceberg head (539g) has 81 calories. Use the slider above for any weight.
Is iceberg lettuce nutritious?
Iceberg lettuce is 96% water and provides minimal nutrition compared to romaine or leaf lettuces. It has very small amounts of most vitamins and minerals. It is not harmful, but provides little beyond hydration and crunch. Choose romaine, red leaf, or green leaf lettuce for meaningful nutritional benefit.
Does lettuce help with sleep?
Possibly. Lettuce contains lactucin — a compound with mild sedative properties. While the amounts in normal servings are small, some traditional medical systems used wild lettuce as a sleep aid. Romaine lettuce broth has been studied for mild sedative effects. The effect is unlikely to be strong from salad alone, but consuming lettuce in the evening is unlikely to hurt sleep.
Is lettuce keto?
Yes — lettuce is one of the most keto-friendly foods. With only 1.6g of net carbs per 100g, it can be eaten freely on ketogenic diets. Lettuce wraps are a popular keto substitute for bread and tortillas.
How long does lettuce last in the fridge?
Whole heads last 1-2 weeks refrigerated. Prewashed, cut lettuce lasts 3-7 days in an airtight container with a paper towel to absorb moisture. Store away from ethylene-producing fruits (apples, bananas) which accelerate wilting.
What is the most nutritious type of lettuce?
Romaine lettuce has the best nutritional profile among common varieties: highest in vitamin A, vitamin K, folate, and vitamin C. Red leaf and green leaf lettuces are close seconds. Butterhead (Boston) lettuce is mild and nutritious. Iceberg is the least nutritious but most hydrating.

Nutrition values sourced from USDA FoodData Central. Not medical advice.