Celery seed has been used as medicine for thousands of years in the Eastern world. During ancient times, Indian Ayurvedic medicine used celery seed to treat colds, flu, water retention, poor digestion, different types of arthritis, and certain diseases of the liver and spleen.

Today, celery seed is used mostly as a diuretic, meaning it helps your body eliminate water by increasing urine output. Celery seed is also used for:

• Treating arthritis and gout
• Helping reduce muscle spasms
• Calming the nerves
• Reducing inflammation
• Lowering blood pressure

There are no human scientific studies that show whether celery seed helps treat these conditions or any others. Studies do show that celery seed acts as a mosquito repellent.

A few animal studies suggest that celery seed extracts may help lower blood pressure and cholesterol, as well as protect the liver from damaging substances such as high doses of the pain reliever acetaminophen (Tylenol). But again, researchers do not know whether those effects apply to humans.

Researchers have found that people who eat a diet rich in lutein, found in celery, spinach, broccoli, lettuce, tomatoes, oranges, carrots, and greens, were less likely to develop colorectal cancer. However, celery was just one part of their diet. So it could be celery, another food, or some combination of foods that lowered their risk of cancer.

The celery plant is slender and stands about 2 to 3 feet tall. It has 3 to 5 segmented leaves and flowers with small white petals. Celery seeds, which are found in the flowers, are very small, tan to dark brown, and have a strong, pleasant smell.

Celery seeds contain several substances, including:

• Volatile oils
• Flavonoids, which are antioxidants that give plants their colors and may protect cells from damage
• Coumarins, chemicals that help thin the blood
• Linoleic acid, an omega-6 fatty acid

Celery seeds are available as:

• Fresh or dried seeds
• Tablets
• Capsules filled with celery seed oil
• Celery seed extract

Pediatric

Scientists have not studied celery seeds in children, so it is not recommended for use in children under 18.

Adult

The dose depends on what you are taking it for and which form you are taking, such as celery seed oil capsules or tablets, extract, or whole celery seeds. Ask your doctor to help you determine the right dose.

The use of herbs is a time-honored approach to strengthening the body and treating disease. However, herbs can have side effects and interact with other herbs, supplements, or medications. For these reasons, you should take herbs under the supervision of a health care provider.

Pregnant women should not use celery seed because it may lead to uterine bleeding and muscle contractions in the uterus, which could cause miscarriage.

People with active kidney inflammation should not take celery seed.

People with low blood pressure should use caution when considering taking celery seed as a supplement.

Some people who are allergic to birch pollen may also be allergic to celery seed.

Some of the chemicals in celery stems and seeds can cause the skin to become very sensitive to the sun's UV rays. Use sunscreen or sunblock lotions.

DO NOT take celery seeds from a gardening packet. These seeds have usually been treated with chemicals.

Few studies have investigated celery seed, so researchers do not really know whether it interacts with other herbs and medications. However, people who take the following medicines should ask their doctors before taking celery seed.

Lithium: Celery seed may alter how this medication is excreted in the body.

Thyroid medications: Celery seed may interact with thyroid medications.

Diuretics (water pills): Celery seed acts as a diuretic. So it could make the effects of other diuretics stronger and raise the risk of dehydration.

Blood-thinning medications (anticoagulants and antiplatelets): Celery seed contains chemicals that may thin the blood. This could make the effects of blood thinners stronger and raise the risk of bleeding. Blood thinners include aspirin, warfarin (Coumadin), and clopidogrel (Plavix).

Other medications: Celery seed may interact with lithium, thyroid medications, and sedatives.

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