Who Should Avoid Celery? Risks and Medical Considerations

December 24, 2025 •

6 min read

According to the European Anaphylaxis Registry, celery was identified as a trigger food in 6% of registered adult cases, highlighting its potential for severe allergic reactions in some individuals. While a nutritious vegetable for most, celery can pose significant risks for certain people, from triggering allergies to interfering with medication and exacerbating specific health conditions.

Quick Summary

This article outlines specific groups who should be cautious or avoid celery, including individuals with allergies, pregnant women, those on certain medications, and people with kidney disease or low blood pressure. It details potential health risks and interactions to promote informed dietary choices.

Key Points

Allergy Warning: Individuals with known celery allergies or related pollen syndromes (like mugwort-birch pollen) must avoid celery, as it can cause reactions from mild itching to severe anaphylaxis.
Pregnancy Precaution: Pregnant women should avoid celery seed extracts and oil due to compounds that can cause uterine contractions and increase miscarriage risk.
Medication Interaction: Celery contains Vitamin K and blood pressure-lowering compounds that can interfere with blood thinners, hypertension medication, and sedatives.
Photosensitivity Risk: High intake of celery, especially alongside UV exposure, can cause phytophotodermatitis, a painful blistering reaction, due to its psoralen content.
Kidney & Blood Pressure Concerns: Those with existing kidney problems or low blood pressure should limit celery intake, particularly concentrated forms like juice, which can exacerbate their conditions.
General Moderation: For those without specific health issues, consuming fresh celery in moderation is safe and nutritious, but excessive intake is not recommended.

Understanding Celery: More Than Just a Crunchy Vegetable

For many, celery is a low-calorie, hydrating, and nutritious vegetable used in everything from soups to salads. However, beneath its crunchy exterior lie compounds that can be harmful to specific populations. The risks associated with celery often stem from its powerful chemical compounds, such as psoralens, coumarins, and natural diuretics, which can have significant physiological effects. While these can be beneficial for some, they are hazardous for others, necessitating a cautious approach.

Individuals with Celery Allergies

Celery is a well-known allergen, particularly in Central Europe, and can cause a wide spectrum of reactions. Allergic responses can range from mild oral allergy syndrome (OAS) to severe anaphylaxis. This is especially true for those with cross-reactivity to mugwort or birch pollen, a phenomenon known as the "celery-mugwort-birch-spice" syndrome. Allergic individuals must be vigilant, as celery and its derivatives (seeds, salt, oils) are often hidden ingredients in processed foods, seasonings, and stocks. For these individuals, avoidance is the only safe option.

Pregnant and Breastfeeding Women

While fresh celery in food amounts is generally safe during pregnancy, certain forms should be avoided. Celery seed extract and celery essential oil contain compounds that can act as uterine stimulants and potentially cause contractions, which increases the risk of miscarriage or premature labor. Due to insufficient evidence regarding its safety during breastfeeding, experts often advise sticking to food amounts and avoiding medicinal supplements. Always consult a doctor before using celery supplements during this sensitive period.

People Taking Specific Medications

Celery contains compounds that can interact with various medications, altering their effectiveness or increasing side effects. For people on certain drug regimens, celery can pose a serious risk. Always inform your healthcare provider of any dietary changes, especially when consuming celery in medicinal or concentrated forms like juice or extract.

A Comparison of Medication Interactions with Celery


Medication Type	Celery Interaction Risk	Mechanism of Action	Recommendation for Patients
Blood Thinners (e.g., Warfarin)	High	The high Vitamin K content in celery can interfere with blood-thinning medications, increasing the risk of bleeding.	Monitor clotting time closely and consult a doctor before incorporating large amounts into the diet.
Blood Pressure Medications	Moderate to High	Celery extract can lower blood pressure, potentially causing it to drop too low when combined with antihypertensive drugs.	Monitor blood pressure and discuss dietary changes with a doctor to avoid dizziness or hypotension.
Sedatives and CNS Depressants	Moderate	Celery can cause sleepiness due to natural sedative properties, which may compound the effects of sedatives.	Avoid combining celery with sedatives to prevent excessive drowsiness or impaired thinking.
Lithium	Moderate	Celery's diuretic effect may decrease how well the body eliminates lithium, potentially leading to toxic levels.	Consult a doctor and monitor lithium levels closely if consuming significant amounts of celery.

Those with Kidney Problems

Celery is celebrated for its mild diuretic properties, which can be beneficial for some but problematic for others. Individuals with pre-existing kidney inflammation or other kidney disorders should avoid consuming celery in medicinal amounts, as it could potentially exacerbate their condition. While animal studies have shown potential benefits, human clinical trials are lacking, and celery juice cleanses can be dangerously high in potassium for those with advanced kidney disease. A renal dietitian's guidance is crucial for anyone with kidney concerns.

People with Low Blood Pressure

Given celery's documented ability to lower blood pressure, individuals who already have low blood pressure should be cautious. Consuming celery in medicinal quantities could cause their blood pressure to drop to an unsafe level, leading to dizziness, lightheadedness, or fainting. Monitoring blood pressure is essential for this group, and moderation is key.

Individuals with Sun Sensitivity

Celery contains phototoxic compounds called psoralens. Ingestion of large quantities or direct skin contact with celery juice followed by exposure to ultraviolet (UV) light can cause phytophotodermatitis, a severe sunburn-like reaction with blistering. This risk is heightened in individuals already taking photosensitizing medications or those exposed to high UV light, such as from tanning beds.

A Concluding Word on Celery Consumption

While a staple for many, celery is not for everyone. The decision to incorporate it into a diet should be made with careful consideration of one's personal health profile, allergies, and current medications. For those with no underlying conditions, celery remains a healthy food choice in moderation. However, for the at-risk populations detailed above, avoidance or careful consultation with a healthcare provider is the wisest course of action to prevent adverse health outcomes. It is a powerful example of how even a seemingly innocuous vegetable can have profound effects on the body under the right—or rather, wrong—circumstances.

List of Potential Issues Associated with Celery Consumption

Allergic Reactions: Can range from mild oral allergy syndrome to life-threatening anaphylaxis.
Medication Interactions: Affects blood thinners, blood pressure medication, and sedatives.
Uterine Contractions: Excessive celery seeds or oil can induce contractions in pregnant women.
Photosensitivity: Psoralens in celery can cause severe skin reactions upon sun exposure.
Low Blood Pressure: Can further lower blood pressure in individuals already suffering from hypotension.
Kidney Complications: High intake of extracts or juice is not recommended for those with kidney disease.
Digestive Discomfort: Excessive consumption, especially in those with sensitivities, can cause bloating and gas.

Conclusion

In conclusion, the seemingly simple celery is a complex vegetable with potent compounds that can affect different individuals in various ways. It's crucial for those with known allergies, pregnant women avoiding supplements, individuals on specific medications, and people with conditions like low blood pressure or kidney disease to exercise caution or avoid celery entirely. For the general population, moderation remains the best approach. By understanding these risks, consumers can make informed decisions to protect their health and well-being, confirming that even the most common foods are not universally suitable for everyone.

Outbound Link

For more information on drug interactions with foods and supplements, consult the National Institutes of Health: https://www.nih.gov/

Comparison Table


Condition/Status	Recommended Celery Consumption	Reason/Risk Factor	Action to Take
Celery Allergy	Avoid completely	Triggers immune response, can lead to anaphylaxis.	Read labels for hidden ingredients and avoid celery in all forms.
Pregnancy	Consume fresh stalks in moderation; avoid supplements	Seeds/oil can cause uterine contractions.	Stick to small amounts of fresh celery and consult doctor about supplements.
Taking Blood Thinners	Consume in moderation; consult doctor	Vitamin K interference can increase bleeding risk.	Regularly monitor clotting time and discuss intake with a healthcare provider.
Low Blood Pressure	Consume cautiously and in small amounts	Contains compounds that lower blood pressure further.	Monitor blood pressure and limit intake to avoid hypotension symptoms.
Photosensitivity	Avoid excessive ingestion and topical application	Psoralens can cause severe sunburn-like skin reactions.	Limit sun exposure after consumption and use sunscreen.

List of Ingredients in Celery to Be Aware Of

Psoralens: Phototoxic chemicals that cause skin sensitivity to UV light.
Vitamin K: A clotting factor that can interfere with blood thinners.
Phthalides: Compounds that may relax blood vessels and lower blood pressure.
Mannitol: A sugar alcohol that can cause digestive issues like bloating in high concentrations.

Final Advice

Ultimately, knowing your own body and its unique sensitivities is the most important step. If you fall into any of the high-risk categories, consulting with a healthcare professional or a registered dietitian before altering your diet is the safest and most responsible course of action. Do not solely rely on anecdotal evidence or general health advice when your health status requires careful consideration. A mindful approach ensures that this common vegetable can be enjoyed by those who can safely benefit from it, while protecting those who cannot.

Frequently Asked Questions

Yes, it is possible to have a celery allergy that is not linked to cross-reactivity with pollen, though the latter is a common cause. Celery contains multiple allergenic proteins, and an allergy can manifest independently.

Initial symptoms can include oral allergy syndrome, such as an itchy mouth, tongue, or throat, but can progress to skin rashes, hives, gastrointestinal upset, or breathing difficulties.

In some cases, yes. The proteins that cause oral allergy syndrome are often heat-sensitive and may be destroyed by cooking. However, more severe celery allergens are heat-resistant, so cooking is not a guarantee of safety for everyone.

Celery juice can concentrate both beneficial compounds and potentially harmful substances like psoralens, which may increase the risk of photosensitivity or medication interactions, especially in large doses.

Check food labels carefully for 'celery,' 'celeriac,' 'celery seed,' 'celery salt,' or any indication of 'spices' or 'flavorings,' as celery can be an undeclared ingredient in certain formulations.

Limited evidence suggests that concentrated celery extract may affect thyroid function, particularly in individuals with pre-existing thyroid disorders. Consultation with a doctor is recommended before using celery supplements if you have a thyroid condition.

Yes, large amounts of celery, particularly celery juice, contain a sugar alcohol called mannitol that can cause digestive issues such as bloating and gas in some individuals.