Beet greens: a leafy green that varies more than most

The strongest study near beet greens is a meta-analysis of 56 exercise trials of nitrate-rich foods, and it found a trivial endurance benefit (standardized mean difference 0.15). That benefit showed up for beetroot. Swiss chard, the leaf form of the same plant species and the closest thing to beet greens that was tested, showed no significant effect, and no trial in it used beet greens themselves. Blood pressure tells a similar story. In a randomized trial of 243 adults aged 50 to 70 with raised pressure, five weeks of leafy greens supplying 300 mg of nitrate a day changed 24-hour systolic pressure by -0.5 mm Hg, against -0.6 mm Hg on placebo, so no better than placebo. On the plate, raw beet greens give about 152 micrograms of folate, 3.2 mg of iron and 74 mg of magnesium per 3.5 oz (100 g) across eight USDA samples, and each figure swings by more than half from sample to sample. Sodium swings most, from 25 to 449 mg per 3.5 oz (100 g) in those same eight samples, and the dataset gives no reason.

The numbers, per 3.5 oz (100 g)

As people eat it, per 3.5 oz (100 g)

How much is actually in it

• Raw beet greens carry about 152 micrograms of folate, 3.2 mg of iron and 74 mg of magnesium per 3.5 oz (100 g), and each of these swings by more than half between samples. — USDA Foundation Foods analytical samples of raw beet greens (n = 8 samples) Evidence E source
  Folate 151.8 ug (range 108.1-190.2), iron 3.163 mg (2.14-4.175), magnesium 74.36 mg (50.3-112.0) per 3.5 oz (100 g)
• Sodium in raw beet greens ranged from 25 to 449 mg per 3.5 oz (100 g) across eight USDA samples, while potassium sat near 370 mg. — USDA Foundation Foods analytical samples of raw beet greens (n = 8 samples) Evidence E source
  Sodium 280.5 mg mean (range 24.83-449.0), potassium 368.7 mg mean (range 321.0-535.0) per 3.5 oz (100 g)

What a real portion looks like

• A cup of raw beet greens weighs about 1.3 oz (38 g), while a cup of cooked greens weighs about 5.3 oz (150 g), so the cooked cup holds roughly four times as much leaf. — USDA FNDDS portion weights for beet greens, raw and cooked Evidence E source
  1 cup raw 38 g, 1 leaf 32 g (food code 72101100); 1 cup cooked 150 g (food code 72101220)

What cooking and storage change

• Boiling and draining greens keeps about 60-65% of folate and 55-60% of vitamin C by the USDA retention table, while iron, magnesium and calcium stay at 95%. — USDA retention factors for the group Vegetables and Vegetable Products, greens boiled and drained Evidence E source
  Little water, drained (Retn_Code 3004): folate 65%, vitamin C 60%, potassium 90%, iron 95%, magnesium 95%; water to cover, drained (3005): folate 60%, vitamin C 55%, potassium 85%, iron 95%
• In infants in northern Spain, vegetable puree kept more than 48 hours before feeding was linked to methaemoglobinemia (OR 24.9), and chard, a leaf of the same species as beet greens, averaged 2,811 mg nitrate per kg. — 78 infants with diet-induced methaemoglobinemia and 78 matched controls, Pamplona 1987-2010 (n = 156) Evidence C source
  Puree prepared >48 h before OR 24.9 (95% CI 3.3-187.6); chard OR 2.0 (95% CI 0.4-8.7, not significant); chard nitrate 2811 mg/kg (n = 17)

What it does to your health

• A meta-analysis of 56 nitrate-food trials found only a trivial endurance benefit from nitrate-rich foods (SMD 0.15), seen for beetroot and not for Swiss chard, the leaf form of the same plant species as beet greens. — Exercise trials of foods rich in nitrate, polyphenols or L-citrulline (118 studies, 56 on nitrate) (n = 56 nitrate studies) Evidence A source
  Nitrate-rich foods SMD 0.15 (p<0.001) on endurance performance; no significant effect for Swiss chard
• In a randomized trial of 243 adults aged 50-70 with raised blood pressure, 5 weeks of leafy green vegetables supplying 300 mg nitrate a day did not lower 24-hour systolic pressure (-0.5 mm Hg vs -0.6 mm Hg on placebo). — 243 subjects, 50-70 y old, clinic systolic BP 130-159 mm Hg, 5 weeks (n = 243) Evidence B source
  Ambulatory SBP change -0.5 +/- 6.6 mm Hg (leafy greens) vs -0.6 +/- 6.2 mm Hg (placebo) vs -1.2 +/- 6.8 mm Hg (potassium nitrate); no significant difference
• In a randomized crossover trial of 38 adults with high-normal blood pressure, 7 days of green leafy vegetables adding at least 300 mg nitrate a day raised plasma nitrate at least fourfold but left blood pressure and arterial stiffness unchanged. — 38 men and women aged 30-70 with systolic blood pressure 120-139 mm Hg, 7-day periods (n = 38) Evidence B source
  Salivary and plasma nitrate and nitrite at least fourfold higher (P<0.001); ambulatory, home and office blood pressure not different between diets

Safety, limits and interactions

• In a small randomized trial of stable warfarin users, 7 days of vitamin K rich vegetables (median 1,100 micrograms vitamin K a day) pushed clotting activity above the therapeutic range in 9 of 13 patients (69%). — Patients on stable warfarin anticoagulation, 1, 2 or 7 days of vitamin K rich vegetables (n = 13 (7-day arm)) Evidence B source
  69% (95% CI 39-91%) above therapeutic level after 7 days; 40% after 1 day and 43% after 2 days
• A single case report describes acute kidney failure from oxalate crystals in a previously healthy 59-year-old woman after one meal of freshly harvested Swiss chard. — One 59-year-old woman, previously kidney-healthy, during a vegetarian diet change (n = 1) Evidence D source
  Acute renal failure with intratubular oxalate crystals; eGFR back to baseline after one year of low-oxalate diet

What people believe that the data does not support

• The EU register lists a digestion claim for Beta vulgaris, the beet plant, as Non-authorized, so it may not appear on EU food labels. — EU Register on nutrition and health claims Evidence E source
  Claim status Non-authorized

The bottom line

A cup of raw leaves weighs about 1.3 oz (38 g) and a cup of cooked greens about 150 g, so the cooked cup holds roughly four times as much leaf. By the USDA table for boiled greens as a group, boiling and draining keeps about 60 to 65 percent of the folate and 55 to 60 percent of the vitamin C. Iron, magnesium and calcium stay at 95 percent. Those factors were set for the food group and were not measured on beet greens. The EU register lists a digestion claim for Beta vulgaris, the beet plant, as non-authorized, which means the evidence did not reach the bar when it was assessed. Who should be careful. If you take warfarin, one small randomized trial matters. After 7 days of vitamin K rich vegetables, 9 of 13 stable patients (69 percent, 95% CI 39 to 91) had clotting activity above the therapeutic range. The abstract does not name the vegetables, and our USDA record has no vitamin K value for beet greens. If you limit sodium or potassium, for example with kidney disease, keep in mind the eighteen-fold sodium spread and potassium near 370 mg per 3.5 oz (100 g). For babies, a case-control study in Spain linked vegetable puree kept more than 48 hours before feeding with methaemoglobinemia (odds ratio 24.9, 95% CI 3.3 to 187.6). Chard in that study averaged 2,811 mg nitrate per kg, its own link was not significant, and beet greens were not tested. One case report describes acute kidney failure from oxalate crystals in a previously healthy 59-year-old woman after a single meal of fresh Swiss chard. It is one person, and it shows only that such harm can happen.

Sources

1. btgr-r2-01 · USDA FoodData Central Foundation Foods, dataset
   Beet greens, raw (FDC 2747653, Foundation Foods): Folate, total 151.8 UG range 108.1-190.2 median 149.9, 8 samples; Iron, Fe 3.163 MG range 2.14-4.175 median 3.11, 8 samples; Magnesium, Mg 74.36 MG range 50.3-112.0 median 69.53, 8 samples
   USDA FoodData Central, Foundation Foods, release 2026-04-30, FDC 2747653 · checked 2026-09-29
2. btgr-r2-02 · USDA FoodData Central Foundation Foods, dataset
   Beet greens, raw (FDC 2747653, Foundation Foods): Sodium, Na 280.5 MG range 24.83-449.0 median 273.3, 8 samples; Potassium, K 368.7 MG range 321.0-535.0 median 350.0, 8 samples
   USDA FoodData Central, Foundation Foods, release 2026-04-30, FDC 2747653 · checked 2026-09-29
3. btgr-r2-03 · USDA FNDDS portion weights, dataset
   Beet greens, raw (FNDDS 72101100, fdc 2709570): 1 cup = 38 g; 1 leaf = 32 g. Beet greens, cooked (FNDDS 72101220, fdc 2709571): 1 cup = 150 g
   USDA FNDDS 2021-2023, food codes 72101100 and 72101220 · checked 2026-09-29
4. btgr-r2-04 · USDA Table of Nutrient Retention Factors, dataset
   USDA-RETN-R6:3004 VEG,GREENS,BOILD,LITTLE WATER DRAIN, group Vegetables and Vegetable Products: vitamin_c_mg 60% retained, folate_total_ug 65%, potassium_mg 90%, iron_mg 95%, magnesium_mg 95%, calcium_mg 95%; USDA-RETN-R6:3005 VEG,GREENS,BOILED,WATER COVER DRAIN: vitamin_c_mg 55% retained, folate_total_ug 60%, potassium_mg 85%, iron_mg 95%, magnesium_mg 95%
   USDA Table of Nutrient Retention Factors, Release 6, 2007, Retn_Codes 3004 and 3005 · checked 2026-09-29
5. btgr-r2-09 · case-control
   A clear relation was found between MHb and use of borage (Borago officinalis) (OR 5.2; 95% CI 1.1-24.6) and maybe chard (Beta vulgaris var cicla) (OR 2.0; 95% CI 0.4-8.7), time from preparation to use (OR 17.4, 95% CI 3.5-86.3 if the purée had been prepared 24-48 hours before and OR 24.9, 95% CI 3.3-187.6 if prepared >48 hours before), and breast-feeding (OR 10.4; 95% CI 1.9-57.2). Tests confirmed that vegetables with the highest nitrate levels were borage (n = 15), with mean nitrate levels of 3968 mg/kg, and chard (n = 17), with mean levels of 2811 mg/kg.
   J Pediatr Gastroenterol Nutr, 2013 · checked 2026-09-29
6. btgr-r2-05 · meta-analysis of RCTs
   Trivial but significant benefits were demonstrated for consumption of nitrate and polyphenol-rich foods (SMD=0.15 and 0.17, respectively, p<0.001) ... Among nitrate-rich foods, beneficial effects were seen for beetroot, but not red spinach or Swiss chard and rhubarb.
   J Int Soc Sports Nutr, 2021 · checked 2026-09-29
7. btgr-r2-06 · RCT
   We enrolled 243 subjects, 50-70 y old, with a clinic systolic BP (SBP) of 130-159 mm Hg. ... The insignificant change in ambulatory SBP (mean ± standard deviation) was -0.6 ± 6.2 mm Hg in the placebo group, -1.2 ± 6.8 mm Hg in the potassium nitrate group, and -0.5 ± 6.6 mm Hg in the leafy green vegetable group.
   Am J Clin Nutr, 2020 · checked 2026-09-29
8. btgr-r2-07 · RCT, crossover
   Thirty-eight men and women ages 30-70 years with systolic blood pressure 120 to 139 mm Hg were recruited to a randomized controlled crossover trial. ... Ambulatory, home, and office blood pressure and arterial stiffness were not different between the high-nitrate diet and the low-nitrate diet.
   Free Radic Biol Med, 2014 · checked 2026-09-29
9. btgr-r2-08 · RCT
   Patients on stable anticoagulant treatment were randomized to either 1 (n = 5), 2 (n = 7) or 7 (n = 13) d with high intake of vitamin-K-rich vegetables (median daily vitamin K intake 1100 micrograms) ... Nine patients (69%; 95% CI, 39-91%) who consumed vitamin-K-rich vegetables for 7 d reached activities above the therapeutic level.
   J Intern Med, 1991 · checked 2026-09-29
10. btgr-r2-10 · case report
    Here, we report the case of a previously kidney-healthy 59-year-old White female presenting with acute renal failure (ARF) with enlarged kidneys after the consumption of one meal of freshly harvested Swiss chard as part of a longer-term vegetarian dietary change.
    BMC Nephrol, 2026 · checked 2026-09-29
11. btgr-r2-11 · EU claims register
    POL-HC-6694 Beta vulgaris Beneficially affects digestion and promotes body’s detoxification processes Non-authorised
    EU Register on nutrition and health claims, claim POL-HC-6694, snapshot 2026-09-21 · checked 2026-09-29