What to Know About Blackjack (Bidens Pilosa)

Medically Reviewed by Dany Paul Baby, MD on April 11, 2022
4 min read

Blackjack (plant) is a common plant that's found in many tropical and subtropical areas around the world. In some countries, it’s considered a weed as it grows densely and quickly. The plant is also known as Bidens pilosa.

The Bidens pilosa plant originated from South America and spread around the world. It has small yellow and white flowers. The fruit is hairy and black. The seeds are small and black. Their stiff bristles allow them to stick easily to clothes or animals' fur. 

Some of the varieties are also known as Spanish needles, beggar-ticks, and devil’s needles.

Experts say that the blackjack plant is a good source of vitamin C. It contains 63 milligrams of vitamin C in 100 grams.

An adult needs about 75 milligrams to 90 milligrams of vitamin C a day. Vitamin C acts as an antioxidant and also helps your body make collagen, which helps your body heal wounds.

Blackjack plant is also a good source of iron (15 milligrams per 100 grams), and zinc (19 milligrams per 100 grams). 

The blackjack plant has been used in traditional medicines for many years. It’s said to be able to treat more than 40 disorders. 

The plant has been reported as useful in treating illnesses such as: 

  • Headache
  • Diarrhea
  • Arthritis  

Scientific research on the blackjack plant has been mostly animal and test-tube studies. More research is needed to find out the benefits of Bidens pilosa on humans. 

Diabetes. Bidens pilosa has been traditionally used as an herb for diabetes. Early studies have found that the compounds in the plant may have an anti-diabetic effect on animals. Research is still in its early stages, and it’s not clear if these findings apply to people. 

Antioxidants.Antioxidants are substances that may delay or prevent some cell damage. This damage is caused by free radicals, which are unstable molecules created when oxygen is metabolized.

An antioxidant-rich diet may help lower your risk of many diseases, such as:

  • Certain cancers, like stomach and bowel cancers
  • Heart disease
  • Liver disease

Plants are rich in antioxidant compounds. Over 200 naturally occurring compounds have been identified from the blackjack plant. These include.

  • 60 flavonoids
  • 25 terpenoids
  • 13 aromatics

So far, the bioactivity of these compounds haven’t been fully investigated. More research is needed to find out the benefits of these compounds.

Anti-inflammatory properties. Another Bidens pilosa benefit is that it may have anti-inflammatory activities. Acute inflammation is your body’s response to injury or illness. This helps start the healing process. But when you’re not sick or injured, and your body continues to send inflammatory cells, this is known as chronic inflammation.

Experts say that chronic inflammation is associated with various diseases like:

  • Cancer
  • Heart disease 
  • Rheumatoid arthritis
  • Type 2 diabetes
  • Alzheimer’s disease

Early studies show that Bidens pilosa extract may be able to reduce inflammation and help reduce immune response. 

High blood pressure. Early research has shown that the compounds in Bidens pilosa may be potentially useful in the prevention of high blood pressure (hypertension). But like many of the benefits of the blackjack plant, more research is needed to find out how this affects people.

Malaria. Scientists say that some of the naturally occurring compounds in the blackjack plant have the potential to be useful against malaria. Malaria is a disease caused by a parasite that infects mosquitos. The use of drugs has resulted in drug resistance in these malaria-causing parasites.

Antibacterial activity. Blackjack plant extract and its compounds may have antibacterial uses. One study found that essential oils of blackjack flowers and leaves had moderate levels of antibacterial activities. Another study found that a compound in the blackjack plant was highly effective against several bacteria, such as the drug-resistant bacteria Methicillin-resistant Staphylococcus aureus (MRSA)

Antifungal use. Bidens pilosa has been used in traditional medicine to treat bacterial infections. Scientists say that the essential oils of the plant have more anti-fungal activity than the extracts. 

Healing wounds. In countries such as Venezuela, Brazil, and Cameroon, the blackjack plant has been traditionally used to treat wounds. Early research found that applying blackjack plant extract may help close wounds faster. 

Skincare. Bidens pilosa extract may have benefits for your skin. An early lab-based study found that some of the components of Bidens pilosa, such as phytanic acid, may have effects on your skin that are similar to retinoids. Topical retinoids that are currently used to treat skin problems may cause side effects such as dryness, burning, and photosensitivity.

The study found that Bidens pilosa may help to maintain the elastin and collagen fibers in your skin. This means it has the potential to be an ingredient in skin-repair and anti-aging skincare products.

The whole plant is used in traditional medicine. Extracts and decoctions are made from the leaves. The leaves and shoots can also be used fresh or dried. The dried plant can be made into a powder that’s used to make teas.

In some countries in Africa, the shoots and young leaves are boiled in sour milk and eaten as vegetables. In the Himalayas, the fresh leaves of the Bidens pilosa are brewed to make tea.

In some countries, the juice of the plant is used in traditional medicine to treat eye irritation, ulcers, and burns.

While the plant has been used for many years in traditional medicine without reports of serious side effects, there have been few scientific studies on its toxicity in humans. One small study found that 400 milligrams of Bidens pilosa taken for 90 days had no obvious side effects.

Experts say that Bidens pilosa is able to grow in water and soil that have high concentrations of metals and cadmium, and absorbs these metals through its roots. This is harmful for people. So be careful when harvesting this plant for food and medical use.

The plant can’t be kept for more than a day after harvesting. After picking the leaves, you can store them in your fridge. To make them last longer, you may also parboil the leaves and dry them in the sun.