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Nutrition · Vegetables

Leafy Greens: The 16 Healthiest, Ranked, Plus Benefits

The 16 healthiest leafy greens ranked by nutrient density, what a cup gives you, what human studies show for blood pressure, bones, eyes and brain, and how to eat more of them.

By Dr. Josh Axe, DC, DNM, CNS·19-min read
Meet the Medical Advisory Board
Evidence-based81 sources citedUpdated October 22, 2026
Published Oct 22, 2026Last updated Oct 22, 2026Editorial policyMedical review policyFact-checking policy
Fresh leafy greens
Leafy greens bring vitamin K, folate, magnesium, potassium, lutein and nitrate in very few calories.
Leafy greens at a glance

Leafy greens are vegetables you eat for the leaf: spinach, kale, lettuces, chard, collards and their cousins, and they pack vitamin K, folate, magnesium, potassium, lutein and nitrate into very few calories. In the nutrient-density ranking, watercress scored 100.00, followed by bok choy at 91.99, Swiss chard at 89.27, beet greens at 87.08 and spinach at 86.43.1

  • Best-supported links: lower blood pressure and fewer heart hospitalizations in a cohort of 53,150 adults,30 fewer fractures with more vitamin K,4245 lower risk of advanced macular degeneration with more lutein,51 and slower cognitive decline at about 1.3 servings a day54
  • Everyday target: at least a cup a day, raw or cooked,30 and half the plate at meals70
  • Sturdy greens such as kale and collards are best gently cooked;71 tender greens such as lettuce, arugula and watercress work well in daily salads
  • If you take warfarin, are prone to kidney stones or have low thyroid or kidney disease, see Who should be careful below

Leafy greens are the vegetables you eat for the leaf itself, and they took the top seven places in a CDC-journal nutrient-density ranking of 47 fruits and vegetables.1 A cup of raw spinach has 7 calories and 145 micrograms of vitamin K, and a cup of chopped dandelion greens has 428 micrograms.615 Leafy greens sit at No. 1 on my list of blood-pressure foods.70

Spinach, arugula and Swiss chard deliver dietary nitrate plus magnesium and potassium, the trio that relaxes and widens arteries.Dr. Josh Axe, DC, DNM, CNSWritten in The High Blood Pressure Protocol (2026), p. 15
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What are leafy greens?

Quick answer

Leafy greens, also called leafy vegetables, are plants eaten for their leaves: spinach, kale, lettuces, chard, collards, mustard and turnip greens, bok choy, watercress, arugula, endive, chicory, dandelion greens, beet greens and cabbage. Dark leafy greens are the deep-green, nutrient-dense members of the group, such as spinach, kale, chard and collards.1

Three families cover most of the list. Leafy cruciferous vegetables include kale, collards, mustard greens, turnip greens, bok choy, watercress, arugula and cabbage. Tender lettuces include romaine, green leaf and iceberg. Bitter greens include endive, chicory, radicchio and dandelion greens, the bitter foods with a sharper bite. Broccoli, green beans and asparagus are green vegetables, and they are eaten for the flower, pod or stalk rather than the leaf.

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  • Slow breathing and a home blood pressure cuff from week 1
  • Potassium at 4,000 to 4,700 mg a day from food, and a ranked top-10 blood-pressure food list led by leafy greens
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Green leafy vegetables list: 16 leafy greens ranked

Quick answer

Watercress ranks first, then bok choy, Swiss chard, beet greens and spinach, in a nutrient-density ranking published in the CDC's journal Preventing Chronic Disease, which averages 17 nutrients per 100 calories in 47 raw fruits and vegetables.1 The score counts nutrients and could not include plant compounds such as lutein and nitrate, so it does not reflect everything that may benefit health, and greens like kale and arugula bring more than their scores show.1

The ranking below follows that score.1 Each entry gives USDA FoodData Central numbers for one raw cup, with the cup's gram weight shown. The FDA Daily Value for vitamin K is 120 micrograms.26

1. Watercress (100.00)

Watercress tops the ranking. One cup chopped (34 grams) has 4 calories, 85 micrograms of vitamin K, 54 micrograms of vitamin A, 14.6 milligrams of vitamin C and 1,962 micrograms of lutein and zeaxanthin.2 Its peppery bite suits salads and sandwiches.

2. Bok choy (Chinese cabbage) (91.99)

The ranking lists Chinese cabbage, a name that covers both bok choy and napa cabbage, and the numbers below are USDA's for bok choy (pak-choi). One cup shredded (70 grams) has 9 calories, 32 micrograms of vitamin K, 156 micrograms of vitamin A, 31.5 milligrams of vitamin C, 46 micrograms of folate and 74 milligrams of calcium.3

3. Swiss chard (89.27)

Swiss chard has broad green leaves on colorful stems. One cup (36 grams) has 7 calories, 299 micrograms of vitamin K, 110 micrograms of vitamin A, 29 milligrams of magnesium and 3,960 micrograms of lutein and zeaxanthin.4

4. Beet greens (87.08)

Beet greens are the leaves above the beet root. One cup (38 grams) has 8 calories, 152 micrograms of vitamin K, 120 micrograms of vitamin A, 290 milligrams of potassium and 0.98 milligrams of iron.5 Save the tops when you buy beets and cook them like chard.

5. Spinach (86.43)

Spinach appears in this page's blood-pressure, calcium and eye studies.344951 One cup (30 grams) has 7 calories, 145 micrograms of vitamin K, 141 micrograms of vitamin A, 58 micrograms of folate, 24 milligrams of magnesium and 3,660 micrograms of lutein and zeaxanthin.6 Cooked and raw spinach were the main food sources of lutein and zeaxanthin in the Nurses' Health Study eye research.51

6. Chicory greens (73.36)

Chicory greens are a bitter salad green. One cup chopped (29 grams) has 7 calories, 86 micrograms of vitamin K, 83 micrograms of vitamin A, 32 micrograms of folate and 2,987 micrograms of lutein and zeaxanthin.7

7. Green leaf lettuce (70.73)

Green leaf lettuce is the loose-leaf lettuce sold in heads and salad mixes. One cup shredded (36 grams) has 5 calories, 45 micrograms of vitamin K, 133 micrograms of vitamin A and 623 micrograms of lutein and zeaxanthin.8

8. Romaine lettuce (63.48)

Romaine lettuce is the crisp heart of a Caesar salad. One cup shredded (47 grams) has 8 calories, 48 micrograms of vitamin K, 205 micrograms of vitamin A and 64 micrograms of folate.9 In the Nurses' Health Study, women who ate lettuce at least once a day had 45% lower hip fracture risk than women who ate lettuce once a week or less.42

9. Collard greens (62.49)

Collard greens are sturdy cooking greens. One cup chopped (36 grams) has 12 calories, 157 micrograms of vitamin K, 90 micrograms of vitamin A, 46 micrograms of folate and 84 milligrams of calcium.10 In an eye disease case-control study, eating spinach or collard greens more often was tied to lower risk.50

10. Turnip greens (62.12)

Turnip greens lead this list for folate and vitamin A per raw cup. One cup chopped (55 grams) has 18 calories, 138 micrograms of vitamin K, 318 micrograms of vitamin A, 107 micrograms of folate, 105 milligrams of calcium and 7,040 micrograms of lutein and zeaxanthin.11

11. Mustard greens (61.39)

Mustard greens have a peppery, mustard-like heat. One cup chopped (56 grams) has 15 calories, 144 micrograms of vitamin K, 39.2 milligrams of vitamin C, 64 milligrams of calcium and 215 milligrams of potassium.12

12. Endive (60.44)

Endive is a crisp bitter green for salads and scoops. One cup chopped (50 grams) has 9 calories, 116 micrograms of vitamin K, 54 micrograms of vitamin A and 71 micrograms of folate.13 Its relative escarole works the same way in soups and salads.

13. Kale (49.07)

Kale is a sturdy cooking green, and its calcium absorbs well. One cup (21 grams) has 7 calories, 82 micrograms of vitamin K, 51 micrograms of vitamin A, 19.6 milligrams of vitamin C, 53 milligrams of calcium and 1,315 micrograms of lutein and zeaxanthin.14 In a study of 11 women, calcium absorption was 40.9% from kale and 32.1% from milk at the same calcium amount, and the researchers called kale a vegetable low in oxalate.48

14. Dandelion greens (46.34)

Dandelion greens lead this list for vitamin K per raw cup. One cup chopped (55 grams) has 25 calories, 428 micrograms of vitamin K, 279 micrograms of vitamin A, 103 milligrams of calcium, 1.71 milligrams of iron and 7,480 micrograms of lutein and zeaxanthin.15 On my show, I have named dandelion greens and mustard greens as spring favorites, with kale and spinach close behind.74

15. Arugula (37.65)

Arugula is a peppery, nitrate-rich salad green. One cup (20 grams) has 5 calories, 22 micrograms of vitamin K, 24 micrograms of vitamin A and 712 micrograms of lutein and zeaxanthin.16 In a study of 18 healthy adults, each person tried each drink, each with 800 mg of nitrate, and systolic pressure fell from 122 to 116 mmHg 150 minutes after a rocket (arugula) salad drink, compared with their own starting values.37

16. Green cabbage (24.51)

Green cabbage is a leafy crucifer you slice for slaws, soups and stir-fries. One cup shredded (70 grams) has 18 calories, 53 micrograms of vitamin K, 25.6 milligrams of vitamin C and 30 micrograms of folate.17 Red cabbage is its purple relative.

Leafy greens ranked by nutrient-density score

Leafy greens ranked by nutrient-density scoreMean % Daily Value of 17 nutrients per 100 calories, raw - 47 fruits and vegetables scored. Watercress: 100 score (max 100); Bok choy (Chinese cabbage): 91.99 score (max 100); Swiss chard: 89.27 score (max 100); Beet greens: 87.08 score (max 100); Spinach: 86.43 score (max 100); Chicory greens: 73.36 score (max 100); Green leaf lettuce: 70.73 score (max 100); Romaine: 63.48 score (max 100); Collard greens: 62.49 score (max 100); Turnip greens: 62.12 score (max 100)Mean % Daily Value of 17 nutrients per 100 calories, raw -47 fruits and vegetables scoredWatercress100 score (max 100)Bok choy(Chinesecabbage)91.99 score (max 100)Swiss chard89.27 score (max 100)Beet greens87.08 score (max 100)Spinach86.43 score (max 100)Chicory greens73.36 score (max 100)Green leaflettuce70.73 score (max 100)Romaine63.48 score (max 100)Collard greens62.49 score (max 100)Turnip greens62.12 score (max 100)
Source: Di Noia J - Preventing Chronic Disease (CDC), 2014 [1]Scores for the 10 highest-ranked leafy greens in the ranking.

Parsley scored 65.59 and chives 54.80, and both are herbs you use by the spoonful; parsley has its own guide.1 Microgreens are seedlings of edible vegetables and herbs, harvested young, and a USDA analysis of 25 microgreens found vitamin C at 20.4 to 147.0 milligrams per 100 grams and lutein and zeaxanthin at 1.3 to 10.1 milligrams per 100 grams.69 Radish greens are edible too. Iceberg lettuce scored 18.28 and is the lightest lettuce here, with 17 micrograms of vitamin K per shredded cup against romaine's 48.1279 Radicchio gives you 102 micrograms of vitamin K in a shredded cup (40 grams),29 and broccoli rabe gives you 90 micrograms in a chopped cup (40 grams).28

A cooked cup holds far more leaves than a raw cup, so the numbers climb. One cup of boiled spinach (180 grams) has 889 micrograms of vitamin K and 20,340 micrograms of lutein and zeaxanthin.18

Cooked green, 1 cup boiled and drainedVitamin KCalcium

Spinach (180 g)

889 mcg18

245 mg18

Mustard greens (140 g)

830 mcg20

165 mg20

Collard greens (190 g)

773 mcg19

268 mg19

Beet greens (144 g)

697 mcg21

164 mg21

Dandelion greens (105 g)

579 mcg22

147 mg22

Swiss chard (175 g)

572 mcg23

102 mg23

Kale (118 g)

493 mcg24

177 mg24

Bok choy (170 g)

58 mcg25

158 mg25

What are the health benefits of leafy greens?

Quick answer

Leafy greens support healthy blood pressure and arteries, eye health and a sharper aging brain, and they are tied to fewer fractures, with human evidence behind each one. In the Danish Diet, Cancer and Health cohort of 53,150 adults, heart benefit leveled off near the nitrate in about a cup of greens a day.30

Where the research stands

The human evidence rests on large cohorts for heart, bone, eye and brain outcomes, plus short trials for blood pressure and bone markers. A long-running Danish cohort ties vegetable nitrate to fewer cardiovascular hospitalizations.30 Short trials in healthy adults show a nitrate-rich serving of greens lowering blood pressure for several hours,3438 and a 4-week trial in 30 adults, each of whom tried all three phases, improved a vitamin K bone marker on about 200 grams of leafy greens a day.47

1

Blood pressure and heart support

Moderate evidenceHuman studyCohort of 53,150 adults; short trials in 18 to 30 healthy adults each; 1- to 5-week trials in 30 to 243 adults with high-normal or raised pressure

In the Danish Diet, Cancer and Health cohort of 53,150 adults followed for a median of 21 years, people getting about 141 mg of vegetable nitrate a day had systolic pressure 2.58 mmHg lower at the start than people getting 23 mg, and over follow-up people getting about 59 mg a day had 15% fewer cardiovascular hospitalizations, 12% fewer ischemic heart disease events, 17% fewer ischemic strokes, 15% fewer heart failure events and 26% fewer peripheral artery disease events; hemorrhagic stroke was not significantly lower.30 The benefit leveled off near 60 mg a day, which the authors estimated as roughly 1 cup of green leafy vegetables.30 A review of 95 prospective studies also tied green leafy vegetables and salads to lower cardiovascular disease and all-cause mortality.58

Short trials show the same direction within hours. In a randomized trial of 19 healthy adults aged 22 to 31, each person tried both lettuces and neither the people nor the researchers knew which lettuce was which, and 50 grams of lettuce grown to carry about 530 mg of nitrate lowered systolic pressure by 4.9 mmHg between 3 and 6 hours compared with low-nitrate lettuce carrying about 3 mg.38 In a trial of 27 healthy adults, each person tried both soups, and spinach soup for 7 days lowered systolic pressure by 3.48 mmHg 3 hours after the last bowl compared with a low-nitrate soup.34 In a trial of 30 healthy adults, each of whom tried each meal, spinach raised plasma nitrite and lowered systolic pressure and pulse pressure compared with a control meal, while diastolic pressure did not change.36 In 30 healthy young adults, each person tried a week of nitrate-rich vegetables (about 400 mg of nitrate at lunch) and a week of beet juice, with no placebo phase; pressure about 2.5 hours after lunch fell during both weeks, as much on vegetables as on beet juice, and fasting pressure did not change.39 Three trials of 1 to 5 weeks in adults with high-normal or raised pressure found no drop in ambulatory or clinic blood pressure: a 5-week trial that randomly assigned 243 adults aged 50 to 70 to leafy greens carrying 300 mg of nitrate a day, nitrate pills or low-nitrate vegetables, 231 of whom finished, in which people did not know which diet was the nitrate-rich one;31 30 adults with mildly raised pressure eating about 200 grams of nitrate-rich vegetables a day for 4 weeks in a trial where each person tried each phase;32 and 38 adults on a 7-day high-nitrate green leafy diet in a trial where each person tried both diets.33 Eat greens every day, as part of meals built around foods that lower blood pressure.

Study takeaway: about a cup of greens' worth of nitrate a day was tied to 15% fewer cardiovascular hospitalizations in 53,150 adults.

About a cup of leafy greens' worth of nitrate a day: fewer heart and artery hospitalizations

About a cup of leafy greens' worth of nitrate a day: fewer heart and artery hospitalizations53,150 Danish adults - 21-year median follow-up - 59 vs 23 mg vegetable nitrate a day. Peripheral artery disease: 26 % lower risk; Ischemic stroke: 17 % lower risk; Heart failure: 15 % lower risk; All cardiovascular disease: 15 % lower risk; Ischemic heart disease: 12 % lower risk53,150 Danish adults - 21-year median follow-up - 59 vs 23mg vegetable nitrate a dayPeripheralartery disease26 % lower riskIschemic stroke17 % lower riskHeart failure15 % lower riskAllcardiovasculardisease15 % lower riskIschemic heartdisease12 % lower risk
Source: Bondonno et al. - European Journal of Epidemiology, 2021 [30]Hemorrhagic stroke was not significantly lower. The study estimated about 60 mg of nitrate as roughly 1 cup of green leafy vegetables.

Greens supply much of the nitrate in the diet, and your body turns it into a vessel-relaxing signal in steps.

1Greens bring the nitrate.

About 80% of the nitrate in the diet comes from vegetables.41 In one large cohort, lettuce provided 41% of vegetable nitrate and spinach 3%.30

2Your saliva concentrates it.

After you absorb it, your salivary glands pull nitrate back out of the blood and concentrate it in saliva.40

3Mouth bacteria do the first step.

Bacteria in your mouth turn that nitrate into nitrite, which you swallow.40

4Nitrite becomes nitric oxide.

In the blood and tissues, nitrite is converted to nitric oxide, a signal that relaxes and widens blood vessels.40

5The mouthwash test shows the pathway at work.

In a mechanism trial, 19 healthy adults used an antiseptic mouthwash for 7 days; their mouths made 90% less nitrite and their blood pressure rose 2 to 3.5 mmHg.40

6What it looks like at the table.

When 26 adults aged 38 to 69 each tried both meals, a meal with 220 mg of nitrate from spinach gave an eightfold rise in salivary nitrite from before the meal to 120 minutes and lowered systolic pressure and pulse pressure compared with the low-nitrate control meal, with measurements up to 210 minutes.35

2

Bone support from vitamin K

Moderate evidenceHuman studyCohorts of 888 to 72,327 adults; meta-analysis of 80,982 people; 4-week trial in 30 adults

Vitamin K helps activate osteocalcin, a protein that binds calcium in bone, and greens are its richest food source, which puts them among the best foods for bone health. In the Nurses' Health Study of 72,327 women over 10 years, women in the higher vitamin K groups had 30% lower hip fracture risk compared with the lowest group, under 109 micrograms a day.42 In the Framingham cohort of 335 men and 553 women averaging age 75 over 7 years, the highest vitamin K quarter (median 254 micrograms a day) had 65% lower hip fracture risk than the lowest (56 micrograms), with no link to bone mineral density.43 In 1,373 Australian women aged 70 and older followed for 14.5 years, vitamin K1 at 99 micrograms a day or more was tied to 31% fewer hospitalizations for any fracture and 49% fewer for hip fracture compared with under 61 micrograms, with the low point near 100 micrograms a day.44 That's about two-thirds of a cup of raw spinach at 145 micrograms per cup.6 A meta-analysis of 80,982 people found the highest dietary vitamin K1 tied to 22% lower fracture risk compared with the lowest.45 In 2,807 Norwegians aged 71 to 75 followed for about 11 years, the lowest vitamin K1 quarter had 57% higher hip fracture risk compared with the highest.46

A controlled trial points the same way. In 30 adults averaging age 62, each of whom tried all three 4-week phases, about 200 grams of green leafy vegetables a day (164.3 micrograms of vitamin K1) lowered undercarboxylated osteocalcin by about 31% compared with a non-vegetable control phase; those are bone-turnover markers, not fractures.47 For calcium amounts per raw cup, turnip greens (105 mg), dandelion greens (103 mg), collards (84 mg) and bok choy (74 mg) lead the USDA records above.1115103 Kale's calcium also absorbs well, as its entry above shows.48

Study takeaway: vitamin K near 100 micrograms a day was tied to about half the risk of hip-fracture hospitalization in 1,373 older women.

3

Eye support from lutein

Moderate evidenceHuman studyCohorts of 102,046 adults; meta-analysis of 6 cohorts; feeding study in 11 adults

Lutein and zeaxanthin are carotenoids that gather in the macula, the center of the retina. In the Nurses' Health Study and Health Professionals Follow-up Study, 63,443 women and 38,603 men followed for about two decades, the highest group for predicted blood lutein and zeaxanthin had 41% lower risk of advanced macular degeneration than the lowest group, with no link to intermediate disease.51 A meta-analysis of 6 cohorts found dietary lutein and zeaxanthin tied to 26% lower risk of late macular degeneration and 32% lower risk of its neovascular form, with no clear link to early disease.52 In a case-control study of 356 people with advanced macular degeneration and 520 without it, the group eating the most carotenoids had 43% lower odds of the disease than the group eating the least.50 Food reaches the eye itself: in 11 adults who added 60 grams of spinach a day for up to 15 weeks, 10 of whom also added 150 grams of corn a day, 8 raised their macular pigment density by 19%, 2 raised blood lutein without a pigment change, and 1 did not respond.53

Study takeaway: the highest lutein group had 41% lower risk of advanced macular degeneration in 102,046 adults.

4

Brain support as you age

Moderate evidenceHuman studyCohort of 960 adults over 4.7 years; cohort of 13,388 women

In Heal Your Cells, Dr. Will Cole and I write that leafy greens are rich in magnesium, folate and vitamin K, and that higher green vegetable intake is directly linked with slower cognitive aging in multiple large-scale studies.71 In the Rush Memory and Aging Project, 960 adults aged 58 to 99 were followed for a mean of 4.7 years, and the top group, at a median of 1.3 servings of green leafy vegetables a day, declined more slowly than the lowest group at 0.09 servings a day by the equivalent of 11 years of age.54 Vitamin K, lutein, folate and nitrate each tracked with slower decline, while beta-carotene showed no clear link.54 In the Nurses' Health Study, 13,388 women with two cognitive assessments 2 years apart declined more slowly by 0.05 units in the highest green leafy group compared with the lowest, about 1 to 2 years younger.55 Greens belong on a brain foods list.

Study takeaway: 1.3 servings a day tracked with decline slower by the equivalent of 11 years of age in 960 older adults.

Leafy greens and the aging brain

Leafy greens and the aging brain960 adults aged 58-99 - Rush Memory and Aging Project - 4.7 years. About 1.3 servings a day: cognitive decline slower by the equivalent of 11 years of age960 adults aged 58-99 - Rush Memory and Aging Project - 4.7yearsAbout 1.3 servings a day:cognitive decline slower bythe equivalent of 11 yearsof age
Source: Morris et al. - Neurology, 2018 [54]Compared with the lowest-intake group (0.09 servings a day).

Greens are also tied to fewer new cases of type 2 diabetes. Leafy greens are No. 1 on my type 2 diabetes food list,79 and in a meta-analysis of 6 cohorts, 4 of which measured green leafy vegetables, greater green leafy vegetable intake was tied to 14% lower risk of type 2 diabetes.56 A second meta-analysis of 251,235 people found 13% lower risk for each added fifth of a serving a day, while total vegetables showed no clear link.57 Greens add fiber and minerals for almost no calories.

How to eat more leafy greens

Quick answer

Eat at least a cup of leafy greens a day, raw or cooked, fill half your plate with greens and vegetables at meals, and dress or cook them with olive oil so you absorb their fat-soluble nutrients.7067

Fill half the plate with potassium- and nitrate-rich color, greens, beets and other vegetables, with a quarter clean protein such as fish, poultry or legumes and a quarter smart carbs.70 Fat helps your body absorb more plant compounds from vegetables, like lutein from dark green vegetables, as well as the fat-soluble vitamins A, D, E and K.77 That pairing has trial support: in a study of 7 adults who each ate three salads, carotenoid absorption was negligible with fat-free dressing and highest with full-fat dressing.67 Adding avocado or avocado oil to a salad also raised absorption in a study of 11 adults, each of whom tried each version: 150 grams of avocado raised lutein absorption 5.1-fold and beta-carotene absorption 15.3-fold, and 24 grams of avocado oil had a similar effect.68 A simple olive oil and lemon dressing does the job; these salad recipes are a good start.

Bitter greens deserve a regular turn. At the first Passover, God told Israel to eat the lamb "roast with fire, and unleavened bread; and with bitter herbs they shall eat it" (Exodus 12:8).78 Scripture doesn't name the plants. Good bitter foods to eat in that spirit include lettuce, endive, chicory, horseradish, dandelion, arugula and watercress.72 When your body tastes bitter, it starts to release more bile, acid and enzymes, which is why I teach bitter greens such as spinach, arugula, dandelion greens and watercress for digestion and the liver.7273 Something we love to cook up in our house is broccoli rabe, also known as rapini. We sauté it in olive oil and garlic with some sea salt, and it's absolutely delicious.72

When my mom was recovering from cancer through nutrition and lifestyle alongside her medical care, she made a green drink every morning: spinach, celery, cucumber, cilantro, lime and a green apple, blended or juiced.75 A drink like that, or one of these green smoothie recipes, is an easy daily cup.

Buy organic when possible, especially for greens you eat whole, and know that organic fresh or frozen vegetables both count, so frozen spinach, kale and collards are fine standbys.76 The dirty dozen list can help you prioritize. Follow the washing steps in the safety section below. For a wider vegetable rotation, see the non-starchy vegetables list and frozen vs. fresh vegetables.

Raw or cooked: which leafy greens are better?

Quick answer

Both count: gently cook sturdy and cruciferous greens such as kale, collards, mustard and turnip greens, bok choy and cabbage, and enjoy tender lettuces, arugula, watercress and baby spinach raw in salads. Gentle cooking, steaming or sautéing, can make some nutrients more available and is easier on the gut.71

Gentle cooking methods like steaming or sautéing can make certain nutrients more available, and cruciferous greens such as kale are easier on the gut lightly steamed than raw.71 A cooked cup also holds far more leaves: spinach goes from a 30-gram raw cup to a 180-gram cooked cup, and kale from 21 grams to 118 grams.6181424 Daily salads suit healthy digestion. People healing their gut do best starting with warm, cooked greens.81 For more, see foods that are more nutritious cooked than raw.

Questions about leafy greens?

Ask Dr. Axe AI. Answers are grounded in this library, with sources shown.

Who should be careful with leafy greens?

Quick answer

Leafy greens are safe everyday food for most people. If you take warfarin, keep your greens steady week to week; if you are prone to calcium-oxalate kidney stones, boil high-oxalate greens and lean on kale; and wash greens under running water before you eat them unless the package says pre-washed.596466

Warfarin and vitamin K. Eat consistent amounts of vitamin K foods week to week, and tell the doctor who manages your INR before a big change in how many greens you eat.59 A systematic review found mixed results, with any effect on blood thinning possibly showing only at high intakes above about 150 micrograms of vitamin K a day, and concluded that the evidence does not support changing eating habits when starting warfarin, with steady habits mattering more.60 In 66 long-term warfarin users, people eating more vitamin K (above 195.7 micrograms a day) kept steadier INR readings than people eating under 126.5 micrograms.61 One cup of cooked spinach carries 889 micrograms, so steady portions matter more than avoidance.18

Oxalates and kidney stones. Oxalates aren't a problem in small amounts, but large amounts can add to the risk of kidney stones in people who are prone to them.71 In three cohorts totaling 240,681 people, the highest oxalate group had 22% higher kidney stone risk in men and 21% higher in older women than the lowest oxalate group, with no association in younger women, and spinach supplied over 40% of oxalate intake; the authors concluded that dietary oxalate is not a major risk factor for kidney stones.62 Raw spinach carries 1,959 milligrams of oxalate per 100 grams and raw chard 874, and boiling moves oxalate into the cooking water.63 In a study of 9 vegetables, boiling cut soluble oxalate by 30% to 87% and the oxalate was recovered in the water, so discard it if kidney stones are your concern.64 Spinach's oxalate binds most of its calcium, so only about 5% was absorbed in a study of 13 adults.49 Kale is a low-oxalate green to lean on.48

Thyroid. With low thyroid, cook cruciferous greens such as kale, collards and bok choy, and skip big raw kale or cabbage smoothies.80

Kidney disease and potassium. Cooked greens are concentrated potassium sources: a boiled cup of beet greens has 1,309 milligrams and a boiled cup of Swiss chard has 961 milligrams.2123 If your care team has set a potassium limit, plan greens within it.

Washing and foodborne illness. Wash all produce under running water with no soap, detergent or produce wash, dry it with a clean towel, use packaged greens labeled pre-washed as directed, and refrigerate lettuce at 40 °F or below.66 In CDC outbreak data from 1998 to 2008, leafy vegetables were linked to more foodborne illnesses than any other of 17 food groups, with norovirus behind most illnesses overall, which is why washing and following recalls matter.65 Know the signs of food poisoning, and get care promptly for bloody diarrhea, high fever or signs of dehydration.

The bottom line

Are leafy greens good for you?

Yes. Leafy greens are among the most nourishing foods you can eat daily: watercress, bok choy, chard, beet greens and spinach lead the nutrient-density ranking, and human research ties them to healthier blood pressure and arteries, fewer fractures, lower risk of advanced macular degeneration and slower cognitive aging.130445154

Fill half your plate with greens and vegetables, dress them with olive oil, gently cook the sturdy ones, and keep a tender salad in the rotation.7071

A cup of greens a day is a simple way to feed your body what it needs to heal and thrive.

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Leafy greens: frequently asked questions

What are leafy greens?

Leafy greens are vegetables you eat for the leaf: spinach, kale, lettuces, chard, collards, mustard and turnip greens, bok choy, watercress, arugula, endive, chicory, dandelion greens, beet greens and cabbage.1

What are dark leafy greens?

Dark leafy greens are the deep-green, nutrient-dense members of the group, such as spinach, kale, Swiss chard, collards and beet greens. Swiss chard, beet greens and spinach hold three of the top five scores in the nutrient-density ranking.1

What is the healthiest leafy green?

Watercress ranks first with a score of 100.00 in the nutrient-density ranking, ahead of bok choy at 91.99 and Swiss chard at 89.27.12 Of the 16 greens ranked here, dandelion greens lead for vitamin K per raw cup at 428 micrograms, and turnip greens lead for folate at 107 micrograms.1511

How many leafy greens should you eat a day?

At least a cup a day, raw or cooked. About 60 mg of vegetable nitrate a day, roughly 1 cup of green leafy vegetables, is where benefit leveled off in a cohort of 53,150 adults, and the top brain-health group ate a median of 1.3 servings a day.3054

Are leafy greens better raw or cooked?

Both are good: gently cook sturdy greens such as kale, collards and bok choy, and enjoy tender lettuces, arugula and watercress raw. Gentle cooking can make some nutrients more available, and a cooked cup of spinach (180 grams) holds far more leaves than a raw cup (30 grams).71186

Are all green vegetables leafy greens?

No. Leafy greens are eaten for the leaf, while broccoli, green beans, peas and asparagus are green vegetables eaten for the flower, pod, seed or stalk.

Is iceberg lettuce a leafy green?

Yes, iceberg is a leafy green and the lightest one here: it scored 18.28 in the ranking, with 17 micrograms of vitamin K per shredded cup against 48 in romaine.1279

Can I eat leafy greens on warfarin?

Yes, keep greens in your diet at a steady amount week to week, and tell the doctor who manages your INR before a big change. One cup of cooked spinach carries 889 micrograms of vitamin K, so steady portions matter.5918

Do leafy greens cause kidney stones?

For most people, no: in 240,681 people, the highest oxalate intake was tied to a modestly higher stone risk in men and older women and none in younger women. If you are prone to calcium-oxalate stones, boil spinach, chard and beet greens, discard the water, and lean on kale, a low-oxalate green.626448

Are frozen leafy greens healthy?

Yes. Organic fresh or frozen vegetables both count on my food lists, so frozen spinach, kale and collards are good standbys.76

Can a greens powder replace leafy greens?

No, whole greens come first. A greens powder works as an insurance policy on days you fall short on vegetables. A cup of raw spinach gives you 7 calories, 0.7 grams of fiber and 145 micrograms of vitamin K.6

Is spinach or kale healthier?

Both earn a daily place. Spinach scored 86.43 and kale 49.07 in the nutrient-density ranking.1 A raw cup of spinach has 145 micrograms of vitamin K, 58 micrograms of folate and 3,660 micrograms of lutein and zeaxanthin,6 against kale's 82 micrograms, 13 micrograms and 1,315 micrograms.14 Kale's calcium absorbs well at 40.9% in 11 women,48 while only about 5% of spinach's calcium was absorbed in 13 adults.49

Which leafy greens are highest in iron?

Boiled spinach leads the cooked greens in the table at 6.43 milligrams of iron a cup,18 then Swiss chard at 3.95 milligrams23 and beet greens at 2.74 milligrams.21 Raw, dandelion greens lead this list at 1.71 milligrams a cup.15

Are the nitrates in leafy greens bad for you?

No. About 80% of dietary nitrate comes from vegetables, and the researchers who measured food nitrate levels concluded their data call into question advice to limit nitrate from plant foods.41

Freshness & method note

October 22, 2026 — Rewritten and re-sourced under Dr. Axe's byline. Ranked 16 leafy greens by nutrient-density score with USDA FoodData Central numbers per raw cup and a cooked-cup table; added the human evidence for blood pressure and heart health, vitamin K and bone, lutein and eye health, and cognitive aging, each with its study design and numbers; added how nitrate relaxes arteries, practical ways to eat more greens, and a raw-or-cooked guide; and gathered warfarin, oxalate, thyroid and washing guidance into one safety section. Removed the unsourced cancer and detox claims and the generic nutrient bullets that the USDA records do not support.

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Dr. Josh Axe

Dr. Josh Axe, DC, DNM, CNS

Doctor of Natural Medicine · Founder, DrAxe.com

Dr. Axe is a certified doctor of natural medicine, clinical nutritionist, and multiple New York Times bestselling author. He has spent 20+ years in clinical practice helping people heal at the root cause and founded one of the most-visited natural-health platforms in the world.

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