Celery: what the blood pressure trials actually gave people

Celery has a real meta-analysis behind it, and the method matters more than the headline. Ten randomised studies pooled together show celery lowering systolic and diastolic blood pressure, fasting glucose and triglycerides, with no effect on total cholesterol, LDL or HDL, and no more adverse events than placebo. In those trials celery came as capsules or decoctions, at capsule doses from 10.55 mg to 2,250 mg a day over 12 to 84 days. The subgroup analysis found celery seed, and preparations above 1,000 mg a day, doing better than other parts of the plant. Nobody in that literature was handed a stalk. The closest thing to a result about food is a cross-sectional study of Americans aged 40 to 59, where cooked celery was one of four cooked vegetables out of twelve that related inversely to blood pressure. In the same data, two standard deviations more cooked vegetables went with systolic pressure lower by 1.3 mm Hg.

The numbers, per 100 g

What cooking and storage change

• Cooking does not reliably destroy what makes celery allergenic, and neither does turning it into spice. — patients with a history of allergic reactions to raw or to raw and cooked celery (n = 12) Evidence C source
  Six of eleven patients had a positive challenge to cooked celery and five of five to celery spice; allergenicity survived in four patients even after thermal treatment equivalent to 76.07 minutes at 100 degrees; heat resistance of the allergens decreased in the order cross-reactive carbohydrate determinants, then Api g 4, then Api g 1
• Cooked celery was one of only four cooked vegetables linked to lower blood pressure in a large diet survey. — Americans aged 40 to 59 (n = 2195) Evidence C source
  Considered singly, four of twelve commonly eaten cooked vegetables, celery, peas, scallions and tomatoes, related significantly inversely to either systolic or diastolic blood pressure; overall, two standard deviations higher cooked vegetable intake went with systolic pressure lower by 1.3 mm Hg without body mass index in the model and 0.9 mm Hg with it

What it does to your health

• Pooled trials show celery preparations lowering blood pressure, fasting glucose and triglycerides. — adults with hypertension, prediabetes, polycystic ovary syndrome or overweight, across ten randomised controlled studies (n = 511) Evidence A source
  Systolic blood pressure SMD -1.0 (95% CI -1.85 to -0.14), diastolic SMD -0.93 (95% CI -1.54 to -0.33), fasting plasma glucose SMD -0.80 (95% CI -1.58 to -0.01) and triglyceride SMD -1.18 (95% CI -1.45 to -0.91); no effect on total cholesterol, LDL or HDL; no significant difference in adverse events against placebo

Safety, limits and interactions

• The dose of celery that sets off a reaction in sensitive people is in the same range as peanut. — European patients with allergy to peanut, hazelnut, celery, fish or shrimp Evidence C source
  The dose eliciting reactions in 10% of the allergic population ranged from 1.6 to 10.1 mg of protein for hazelnut, peanut and celery, with overlapping 95% confidence intervals; fish sat higher at 27.3 mg and shrimp very much higher at 2.5 g of protein

What people believe that the data does not support

• The trials behind celery and blood pressure gave people capsules and decoctions, not celery. — participants with hypertension, polycystic ovary syndrome, prediabetes or overweight in trials run in Iran, Indonesia and China between 2002 and 2024 (n = 511) Evidence A source
  Celery was given as capsules or decoctions, with capsule doses from 10.55 mg to 2,250 mg per day over 12 to 84 days; the subgroup analysis reported that celery seeds or preparations above 1,000 mg per day worked better than other parts of the plant
• Both health claims ever filed for celery in Europe were refused, including the one about flushing out fluid. — — Evidence E source
  The register holds two entries naming Apium graveolens and both carry the status Non-authorised; the refused wording covers enhancing renal elimination of water, facilitating the elimination functions of the organism, drainage of the organism and contributing to the urinary tract; authorised claims for celery number zero

Who this works differently for

• In fifty people already on blood pressure medication, 1.34 g a day of celery seed extract for four weeks lowered self-reported anxiety and depression scores, and nothing here separates that from the drugs they were taking. — hypertensive patients already on medication (n = 50) Evidence B source
  Mean reduction of 6.78 points on the Beck anxiety inventory (P < 0.001) and 3.63 points on the depression inventory (P < 0.01), with significant improvement in specific symptoms including inability to relax, nervousness, dizziness and insomnia, and a significant mean reduction in blood pressure parameters during celery treatment

What is still unknown

• Celery is a leading dietary source of the compounds suspected in melanoma, and almost nobody has measured how much of them it delivers. — twenty publications based on nineteen epidemiological studies Evidence C source
  All but two of the nineteen studies examined only parts of the furocoumarin-containing food spectrum and could not quantify total dietary furocoumarin intake; the qualitative synthesis found moderate evidence that higher dietary furocoumarin intake acts as a risk factor for cutaneous melanoma, without being able to say whether or how much it raises risk

The bottom line

The celery juice cleanse has a regulatory answer. Europe has considered exactly two health claims for celery and refused both, and the refused wording is the language the cleanse is sold with: enhancing renal elimination of water, facilitating the elimination functions of the organism, drainage of the organism, contributing to the urinary tract. Authorised celery claims in that register number zero. Celery allergy deserves more respect than it usually gets. In European challenge data, the dose that sets off a reaction in 10 percent of allergic people fell between 1.6 and 10.1 mg of protein for hazelnut, peanut and celery alike, with overlapping confidence intervals. Cooking does not reliably fix it. Six of eleven challenged patients reacted to cooked celery and five of five to celery spice, and in four of them the allergenicity survived heating equivalent to 76 minutes at 100 degrees. If you react to celery, celery salt and stock powder count as celery. One open question we would rather flag than bury. Celery is a leading dietary source of furocoumarins, and a review of nineteen studies found moderate evidence that higher furocoumarin intake is a risk factor for melanoma. All but two of those studies could not quantify how much anyone was getting. Nobody can yet say what amount of celery that would mean, and we would rather tell you so than pick the tidier answer.

Sources

1. cel-dr-04 · double-blind placebo-controlled food challenge
   In a subset of patients with a positive DBPCFC to cooked celery, celery remains allergenic even after extended thermal treatment (76.07 min/100 degrees C).
   Allergy, 2002 · checked 2026-09-22
2. cel-dr-06 · cross-sectional multicentre study
   Considered singly, four of 12 commonly eaten cooked vegetables—celery, peas, scallions, and tomatoes—related significantly inversely to either SBP or DBP (Table 2).
   J Hum Hypertens, 2014 · checked 2026-09-22
3. cel-dr-01 · systematic review and meta-analysis of randomised controlled trials
   The results demonstrated significant therapeutic effects of celery on systolic blood pressure (SMD: -1.0; 95% CI: -1.85 to -0.14), diastolic blood pressure (SMD: -0.93; 95% CI: -1.54 to -0.33), fasting plasma glucose (SMD: -0.80; 95% CI: -1.58 to -0.01), and triglyceride (SMD: -1.18; 95% CI: -1.45 to -0.91).
   Front Nutr, 2025 · checked 2026-09-22
4. cel-dr-05 · threshold dose distribution from double-blind placebo-controlled challenges
   Of the 5 foods used for challenge, 4 produced similar dose distributions, with estimated doses eliciting reactions in 10% of the allergic population (ED10), ranging from 1.6 to 10.1 mg of protein for hazelnut, peanut, and celery with overlapping 95% CIs.
   J Allergy Clin Immunol, 2015 · checked 2026-09-22
5. cel-dr-02 · characteristics of trials included in a meta-analysis
   Celery was administered either as capsules or as decoctions, with capsule doses ranging from 10.55 mg to 2,250 mg per day, and treatment durations varying from 12 to 84 days.
   Front Nutr, 2025 · checked 2026-09-22
6. cel-dr-07 · regulatory register entry
   POL-HC-6622 Apium graveolens - common name : celery Used to enhance the renal elimination of water / "Used to facilitate the elimination functions of the organism" / "Used for the drainage of the organism" / "Stimulates the elimination function of the organism" / "Contributes to the functionary of the urinary tract" Non-authorised
   EU Register on nutrition and health claims, заява POL-HC-6622, знімок 2026-09-21 · checked 2026-09-22
7. cel-dr-03 · randomised triple-blind placebo-controlled cross-over trial
   In the celery treatment step, the mean reduction in BAI and BDI scores were 6.78 (P < 0.001) and 3.63 (P < 0.01), respectively.
   Inflammopharmacology, 2023 · checked 2026-09-22
8. cel-dr-08 · systematic review of observational studies
   With the exception of two studies [35,36], all other investigations examined only parts of the furocoumarin-containing food and beverage spectrum and were thus not able to quantify the total level of dietary furocoumarin intake.
   Nutrients, 2025 · checked 2026-09-22