Parsley: a vitamin K food eaten by the sprig

Parsley has been tested in people only a handful of times, and the randomized trials found little to report. In 18 healthy volunteers, 5 g of dried parsley a day for 7 days, supplying 84 mg of apigenin, had no significant effect on platelet aggregation or other clotting measures, though apigenin in blood could not be measured to confirm exposure. Those were healthy people, so the result says nothing about anyone on warfarin, for whom the issue is vitamin K. In a crossover trial of 14 adults eating parsley for a week, only 0.58% of the apigenin eaten was recovered in urine, with a wide spread between people. What parsley clearly has is vitamin K, and even that number is uncertain. The USDA record gives fresh parsley 1,640 mcg per 3.5 oz (100 g). The UK table gives 548 mcg, a threefold gap that neither table explains by variety or season. US serving size rules class parsley as a garnish or flavoring vegetable, and in US survey portions a sprig weighs about 1 g and a cup about 60 g. On the USDA figure that puts a garnish at roughly 16 to 66 mcg and a cup near 980 mcg, estimates recalculated from the 100 g value rather than measured per portion, and on the UK figure a cup is closer to 330 mcg.

The numbers, per 3.5 oz (100 g)

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

How much is actually in it

• In the USDA reference record, 3.5 oz (100 g) of fresh parsley holds 1,640 mcg vitamin K, 133 mg vitamin C and 421 mcg vitamin A (RAE). — USDA SR Legacy record Parsley, fresh (n = 1 record) Evidence E source
  Vitamin K 1,640 mcg (1,367% DV), vitamin C 133 mg (148% DV), vitamin A 421 mcg RAE (47% DV) per 3.5 oz (100 g)
• The UK food table gives fresh parsley 548 mcg vitamin K1, 190 mg vitamin C, 7.7 mg iron and 200 mg calcium per 3.5 oz (100 g), a third of the USDA vitamin K figure. — CoFID 2021 record Parsley, fresh, code 13-844 (n = 1 record) Evidence E source
  Vitamin K1 548 mcg, vitamin C 190 mg, carotene 4,040 mcg, iron 7.70 mg, calcium 200 mg per 3.5 oz (100 g)

What a real portion looks like

• US survey portions put a sprig of parsley at 1 g, an unspecified amount at 4 g and a cup at 60 g, so a garnish gives about 16 to 66 mcg vitamin K and a cup about 980 mcg. — FNDDS food Parsley, raw, code 75119000, fdc_id 2709796 (n = 3 portions) Evidence E source
  1 sprig 1 g, quantity not specified 4 g, 1 cup 60 g, vitamin K recalculated from 1,640 mcg per 3.5 oz (100 g)
• US serving size rules place fresh or dried parsley in the category of vegetables used mainly for garnish or flavor, not with vegetables eaten as a side dish. — US food labeling, reference amounts customarily consumed, 21 CFR 101.12(b) Evidence E source
  Parsley listed as an example in the garnish or flavor vegetable category

What your body absorbs

• In a crossover RCT of 14 adults eating parsley for a week, only 0.58% of the apigenin eaten was recovered in urine. — Seven men and seven women, controlled low-flavone diet for 2 weeks, parsley providing 3.73-4.49 mg apigenin/MJ in one week (n = 14) Evidence B source
  Urinary apigenin 0.58% (SE 0.16) of intake, excretion 1.59-409.09 micrograms/MJ per 24 h on parsley vs 0-112.27 on basic diet

What cooking and storage change

• By the USDA table for leafy greens, boiling in a little water and draining keeps 60% of vitamin C and 65% of folate, while minerals keep 90 to 95%. — USDA retention factors, group Vegetables and Vegetable Products, method VEG,GREENS,BOILD,LITTLE WATER DRAIN Evidence E source
  Vitamin C 60% retained, folate 65%, thiamin 85%, potassium 90%, iron and calcium 95%

What it does to your health

• In a crossover RCT of 18 healthy volunteers, 5 g of dried parsley a day for 7 days, giving 84 mg apigenin, did not change platelet aggregation or other clotting measures. — 18 healthy volunteers, 5 g dried parsley/d providing 84 mg apigenin/d, onions or placebo for 7 d each (n = 18) Evidence B source
  No significant effect on platelet aggregation, thromboxane B2, factor VII or other hemostatic variables
• In a non-randomized 8-week study of 85 obese women, 100 g a day of parsley seed bread with a low-calorie diet was followed by better kidney markers that reverted once the bread was stopped. — 85 obese women (BMI 35.68), 100 g ground parsley seed bread with low caloric regimen for four weeks, then Baladi bread for four weeks (n = 85) Evidence C source
  EGFR, creatinine clearance and IL-10 increased, osteopontin, creatinine and IL-1b decreased in phase 1, values returned after omission

Safety, limits and interactions

• According to NIH ODS, people taking warfarin and similar anticoagulants need a consistent vitamin K intake from food and supplements, because sudden changes can increase or decrease the anticoagulant effect. — people taking warfarin (Coumadin) and similar anticoagulants Evidence E source
  Sudden changes in vitamin K intake can increase or decrease the anticoagulant effect
• A single case report describes a kidney transplant recipient whose sirolimus blood level became supratherapeutic after eating excessive parsley. — one renal transplant recipient on sirolimus (n = 1) Evidence D source
  Supratherapeutic sirolimus blood level attributed to excessive parsley intake

What people believe that the data does not support

• The kidney stone reputation of parsley rests on laboratory data suggesting that an ethanolic extract reduced calcium oxalate crystal formation in rats. — rat model of calcium stone formation, ethanolic parsley extract Evidence D source
  Prevented nucleation and precipitation of calcium oxalate, urine supersaturation and urinary protein excretion in rats
• The EU has no authorized claim for parsley itself, but it authorizes the claim that vitamin K, the nutrient parsley is richest in, contributes to normal blood clotting. — EU food labeling, Regulation (EC) No 1924/2006 register Evidence E source
  Authorized claim for vitamin K (blood clotting), no entry for parsley by name

What is still unknown

• A 2023 scoping review of 1,738 papers on culinary doses of herbs for metabolic syndrome found no relevant clinical research on parsley. — clinical trials of culinary doses of herbs and spices in healthy people or people with metabolic syndrome (n = 1738 papers screened) Evidence C source
  No relevant study for parsley

The bottom line

Who should be careful: people on warfarin and similar anticoagulants. According to the NIH Office of Dietary Supplements, they need a steady vitamin K intake, because sudden changes can raise or lower the effect of the drug. That position is about vitamin K in general, and parsley matters to it only because of how much vitamin K it carries. So a sprig on a plate is a different thing from a large bowl of tabbouleh on one day and none the next. A single case report describes a kidney transplant recipient on sirolimus whose blood level of the drug went above range after eating excessive parsley. The amount was not stated and the link is possible, not proven. We have no card on parsley in pregnancy. The idea that parsley prevents kidney stones rests on laboratory data suggesting that an ethanolic extract reduced calcium oxalate crystal formation in rats. We found no human trial. A 2023 scoping review that screened 1,738 papers on culinary doses of herbs and metabolic syndrome found no relevant clinical research on parsley at all. The one human study pointing to kidney markers used bread made from 3.5 oz (100 g) of ground parsley seed a day, not leaves, in 85 women with obesity who were also on a low-calorie diet. It was not randomized, had no parallel control, and the markers slipped back once the bread stopped. It is not a guide to eating parsley seed, and we have no card on the safety of seed at that amount. The EU register holds no health claim for parsley by name. It does authorize the claim that vitamin K contributes to normal blood clotting, the nutrient parsley is richest in, and the minimum amount a food needs to carry that claim is not in the register row we read. On cooking, the USDA factor for leafy greens boiled in a little water and drained keeps 60% of vitamin C and 65% of folate. That is a group factor, not measured on parsley, and the table has no factor for vitamin K.

Sources

1. prsl-r8-01 · USDA FoodData Central SR Legacy, dataset
   Parsley, fresh (FDC 170416, SR Legacy, Vegetables and Vegetable Products): vitamin K 1640 mcg = 1367% DV; vitamin C 133 mg = 148% DV; vitamin A 421 mcg RAE = 47% DV per 100 g; Foundation samples 0
   USDA FoodData Central, SR Legacy, FDC 170416 · checked 2026-09-28
2. prsl-r8-02 · CoFID 2021, dataset
   Parsley, fresh (CoFID 2021, code 13-844, group H): Vitamin K1 548.00 ug; Vitamin C 190 mg; Carotene 4040 ug; Iron 7.70 mg; Calcium 200 mg per 100 g
   CoFID 2021 (Public Health England), code 13-844, OGL v3.0 · checked 2026-09-28
3. prsl-r8-03 · FNDDS portions, dataset
   Parsley, raw (FNDDS 75119000, fdc_id 2709796): 1 sprig = 1 g; Quantity not specified = 4 g; 1 cup = 60 g
   USDA FNDDS, food code 75119000, fdc_id 2709796 · checked 2026-09-28
4. prsl-r8-13 · FDA final rule, Federal Register
   Vegetables, primarily used for garnish or flavor, e.g., pimento, parsley, fresh or dried)
   FDA, Food Labeling: Serving Sizes, Reference Amounts Customarily Consumed, FR Doc. 2016-11865 · checked 2026-09-28
5. prsl-r8-05 · RCT, crossover, 1 week per arm
   Seven men and seven women participated in a randomized crossover trial to study the effect of intake of parsley (Petroselinum crispum), containing high levels of the flavone apigenin, on the urinary excretion of flavones and on biomarkers for oxidative stress. ... The fraction of apigenin intake excreted in the urine was 0.58 (SE 0.16)% during parsley intervention.
   Br J Nutr, 1999 · checked 2026-09-28
6. prsl-r8-04 · USDA Retention Factors Release 6, dataset
   USDA-RETN-R6:3004 VEG,GREENS,BOILD,LITTLE WATER DRAIN: vitamin_c_mg 60%; folate_total_ug 65%; thiamin_mg 85%; potassium_mg 90%; iron_mg 95%; calcium_mg 95%
   USDA Table of Nutrient Retention Factors, Release 6 (2007), code 3004 · checked 2026-09-28
7. prsl-r8-06 · RCT, crossover, 7 days per arm
   fed 18 healthy volunteers 220 g onions/d providing 114 mg quercetin/d, 5 g dried parsley/d providing 84 mg apigenin/d, or a placebo for 7 d each in a randomized crossover experiment with each treatment period lasting 2 wk. ... No significant effects of onions or parsley were found on platelet aggregation, thromboxane B2 production, factor VII, or other hemostatic variables.
   Am J Clin Nutr, 1998 · checked 2026-09-28
8. prsl-r8-07 · clinical trial, non-randomized
   A total of 85 obese women (BMI, 35.68 ± 0.47 kg/m2) participated in an 8-week nutritional intervention comprising two phases. In the first phase, participants consumed 100 g of ground parsley seed bread along with a healthy balanced low caloric regimen for four weeks. ... eGFR, creatinine clearance, IL-10 increased. However, these improved values returned to elevated levels after the omission of the supplement in the second phase.
   Clin Nutr ESPEN, 2024 · checked 2026-09-28
9. prsl-r8-08 · NIH ODS fact sheet
   People taking warfarin and similar anticoagulants need to maintain a consistent intake of vitamin K from food and supplements because sudden changes in vitamin K intakes can increase or decrease the anticoagulant effect
   NIH Office of Dietary Supplements, Vitamin K Fact Sheet for Health Professionals · checked 2026-09-28
10. prsl-r8-09 · case report
    We report a case of a renal transplant recipient who had a supratherapeutic blood level of sirolimus due to consuming excessive parsley to highlight a possible herb-drug interaction.
    Ther Adv Drug Saf, 2021 · checked 2026-09-28
11. prsl-r8-10 · review of preclinical data
    Its ethanolic extract prevented the nucleation and precipitation of calcium oxalate, urine supersaturation, and urinary protein excretion in a rat model of calcium stone formation [27].
    Int J Mol Sci, 2018 · checked 2026-09-28
12. prsl-r8-12 · EU health claim register
    POL-HC-6523 Vitamin K Vitamin K contributes to normal blood clotting Authorised
    EU Register on nutrition and health claims, claim POL-HC-6523, snapshot 2026-09-21 · checked 2026-09-28
13. prsl-r8-11 · scoping review
    Out of a total of 1738 papers identified, there were 142 relevant studies on black pepper, chilli, cardamom, cinnamon, coriander, cumin, fennel, fenugreek, garlic, ginger, nigella seed, rosemary, sage and turmeric. No relevant research was found for cloves, mint, oregano, parsley or thyme.
    Nutrients, 2023 · checked 2026-09-28