What Science Says About Celery
1. Blood pressure
A 2025 meta-analysis pooled nine randomised trials (ten intervention arms, 511 adults) of celery preparations — mostly seed extracts, seed powder, leaf powder or decoctions. Systolic and diastolic blood pressure were lower than in control groups (standardised mean differences −1.0 and −0.93). The clearest effect came from seed preparations and doses above 1,000 mg a day; the trials were small, all conducted in Asia and highly heterogeneous, and none used celery juice. [1]
The best single trial: 52 adults with hypertension took 1.34 g of celery seed extract daily for four weeks in a triple-blind, placebo-controlled crossover design. Twenty-four-hour ambulatory systolic pressure fell from 141.2 to 130.0 mmHg and diastolic from 92.2 to 84.2 mmHg, with no meaningful change on placebo. [2]
2. Fasting glucose and triglycerides
The same meta-analysis found lower fasting glucose (six trials) and lower triglycerides (three trials); total, LDL and HDL cholesterol did not change significantly. [1] In the crossover trial above, fasting glucose fell from 108.53 to 97.96 mg/dL on the seed extract. [3]
3. Uric acid
In a randomised, double-blind, placebo-controlled trial in 28 adults with metabolic syndrome, 150 mg a day of a celery seed extract standardised to 3-n-butylphthalide for twelve weeks lowered uric acid from 297.4 to 261.7 µmol/L and systolic pressure from 121.0 to 115.7 mmHg compared with placebo. Insulin sensitivity did not change. [4]
4. Phthalides — the compounds behind the aroma
Of the twelve most potent odorants identified in raw celery leaves and stalks, the phthalides — 3-n-butylphthalide, sedanenolide and the trans- and cis-sedanolides — were the most important to its character. [5] 3-n-butylphthalide is the compound behind a stroke medicine approved in China in 2002, and it is the molecule the uric-acid trial above standardised its extract to. [6] [4]
5. Dietary nitrate
In EU monitoring data covering 387 samples, celery carried a median of 693 mg of nitrate per kilogram fresh weight, with a mean of 1,103 mg/kg and a 95th percentile of 3,319 mg/kg. [7] Leaves hold roughly twice as much nitrate as stalks. [8]
6. Apigenin — an interesting molecule with thin human evidence
Celery contains the flavone apigenin, but where it sits matters: the USDA flavonoid database lists 78.65 mg of apigenin per 100 g for dried celery seed, a spice, not the fresh stalk, and the leaves carry more phenolic compounds than the stalks. [9] [8] Apigenin is widely discussed in connection with sleep, but a 2024 review notes that the human trials behind those claims used chamomile extract rather than apigenin on its own, and that clinical studies of apigenin alone are still needed. [10]
What has not been studied
No controlled trial has tested celery stalk juice. The one published report on the juice itself describes a single 74-year-old man whose blood pressure fell over six months of daily celery juice while he was also receiving other care; the author notes that one case cannot establish cause and effect. [11] The findings above come from concentrated seed and leaf preparations and describe the plant, not a promise about the juice.
Allergy and sensitivity
Celery is one of the fourteen allergens that must be declared on food labels in the EU. [12] Severe reactions occur mainly in people sensitised to mugwort pollen; in a 2024 study, sensitisation to the celery protein Api g 7 was linked to a markedly higher risk of anaphylaxis. [13] Celery also contains furanocoumarins, compounds that can make skin more sensitive to sunlight; levels in fresh stalks are low but rise several-fold during long storage and fungal infection. [14]
References
- Liu D, Zhao H, Xu H, Hu J. Effects of celery (Apium graveolens) on blood pressure, glycemic and lipid profile in adults: a systematic review and meta-analysis of randomized controlled trials. Front Nutr. 2025;12:1597680. doi:10.3389/fnut.2025.1597680
- Shayani Rad M, Moohebati M, Mohajeri SA. Effect of celery (Apium graveolens) seed extract on hypertension: a randomized, triple-blind, placebo-controlled, cross-over, clinical trial. Phytother Res. 2022;36(7):2889–2907. doi:10.1002/ptr.7469 · PMID 35624525
- Shayani Rad M, et al. Safety evaluation and biochemical efficacy of celery seed extract (Apium graveolens) capsules in hypertensive patients: a randomized, triple-blind, placebo-controlled, cross-over, clinical trial. Inflammopharmacology. 2022;30(5):1669–1684. doi:10.1007/s10787-022-00986-0
- Pérez-Rubio KG, Escobedo-Gutiérrez MJ, Cortez-Navarrete M, Martínez-Abundis E. Effect of celery seed (Apium graveolens L.) administration on the components of metabolic syndrome, insulin sensitivity, and insulin secretion: a clinical trial. Pharmaceuticals. 2026;19(1):110. doi:10.3390/ph19010110
- Kurobayashi Y, Kouno E, Fujita A, Morimitsu Y, Kubota K. Potent odorants characterize the aroma quality of leaves and stalks in raw and boiled celery. Biosci Biotechnol Biochem. 2006;70(4):958–965. doi:10.1271/bbb.70.958
- Wang Y, Shen Y, Liu Z, et al. Dl-NBP (dl-3-n-butylphthalide) treatment promotes neurological functional recovery accompanied by the upregulation of white matter integrity and HIF-1α/VEGF/Notch/Dll4 expression. Front Pharmacol. 2020;10:1595. doi:10.3389/fphar.2019.01595
- EFSA Panel on Contaminants in the Food Chain (CONTAM). Nitrate in vegetables — scientific opinion of the Panel on Contaminants in the Food Chain. EFSA J. 2008;689:1–79.
- Golubkina N, et al. Yield, growth, quality, biochemical characteristics and elemental composition of plant parts of celery leafy, stalk and root types grown in the Northern Hemisphere. Plants. 2020;9(4):484. doi:10.3390/plants9040484
- US Department of Agriculture, Agricultural Research Service. USDA Database for the Flavonoid Content of Selected Foods, Release 3.3. 2018.
- Kramer DJ, Johnson AA. Apigenin: a natural molecule at the intersection of sleep and aging. Front Nutr. 2024;11:1359176. doi:10.3389/fnut.2024.1359176
- Illes JD. Blood pressure change after celery juice ingestion in a hypertensive elderly male. J Chiropr Med. 2021;20(2):90–94. doi:10.1016/j.jcm.2021.04.001
- Regulation (EU) No 1169/2011 on the provision of food information to consumers, Annex II: substances or products causing allergies or intolerances.
- Ballmer-Weber BK, Wangorsch A, Bures P, et al. New light on an old syndrome: role of Api g 7 in mugwort pollen–related celery allergy. J Allergy Clin Immunol. 2024;154:679–689.e5.
- Aharoni N, Afek U, Finkelstein E, et al. Impact of celery age and infection by Botrytis cinerea on linear furanocoumarin (psoralens) content in stored celery. Phytoparasitica. 1996;24:195–197. doi:10.1007/BF02981418