The Health Benefits of Neem

Neem capsules, powder, tincture, oil, and creams

Verywell / Anastasia Tretiak 

Neem (Azadirachta indica) is a type of evergreen tree native to India. In Ayurvedic medicine, neem extract has long been used for a variety of health-related purposes including asthma, constipation, cough, diabetes, gastric ulcers, indigestion, periodontal disease, and urinary tract infection.

Neem is also purported to reduce inflammation, improve liver health, alleviate pain, preserve eyesight, stimulate the immune system, and protect against heart disease.

Neem is sold in capsule, tincture, powder, oil, cream, and mouthwash forms. While neem oil is generally applied to the scalp or skin to treat conditions like dandruff and acne, the extract of the neem leaf is typically taken orally. In some cases, the bark, flowers, and fruit of the neem tree are also used medicinally.

Health Benefits

Although few scientific studies have tested the health effects of neem, there is some evidence that it may offer certain benefits. Here's a look at some key findings from available research.

Dental Health

Neem may help fight plaque buildup and prevent gingivitis, several studies suggest.

In a 2017 study, 20 subjects were given mouthwash with either chlorhexidine gluconate, a substance commonly used to prevent gum disease, or neem. The researchers found neem mouthwash was as effective as the medication and suggested that neem may be a cost-effective alternative to chlorhexidine gluconate treatments.

In an earlier study published in the Journal of Ethnopharmacology in 2004, 36 men were assigned to six weeks of treatment with either a gel containing neem extract or a mouthwash containing chlorhexidine gluconate. Study results showed that the neem-based gel was more effective in reducing plaque buildup than the mouthwash.

In addition, a study published in the Indian Journal of Dental Research in 1999 determined that the use of chewing sticks made with neem extract may help protect against the buildup of bacteria associated with cavity formation and periodontal disease.

Dandruff

Anecdotal evidence suggests neem oil helps relieve dandruff, but the precise mechanism of action is unclear. Dandruff can be caused by dry skin, a fungal infection, contact dermatitis, or other skin conditions. 

Neem oil’s natural antifungal and anti-inflammatory properties may help treat the underlying cause of a flaking scalp and relieve symptoms. 

In laboratory studies, a terpene found in neem called nimbidin was found to inhibit the inflammatory response. This may account for its potential success in treating inflammatory skin conditions that cause dandruff. 

Acne

The topical application of neem oil may be helpful in the treatment of acne and other skin conditions due to its anti-inflammatory and antimicrobial properties. 

In laboratory studies, a proprietary preparation of neem oil using solid lipid nanoparticle technology was found to have an antibacterial effect on acne-causing microbes. The study authors noted that the oil may be used successfully as a long-term acne treatment.

Ulcers

Neem shows promise in the treatment of gastric ulcers, suggests a 2009 report from Phytotherapy Research. Analyzing findings from preliminary studies, scientists concluded that neem bark extract supplements may help aid in ulcer control possibly by inhibiting the secretion of gastric acids.

Cancer

A 2011 research review published in Cancer Biology & Therapy indicates that neem may offer anti-cancer benefits, including immune-stimulating and tumor-suppressing properties.

However, there is currently a lack of clinical trials testing the effectiveness of neem in the prevention or treatment of any type of cancer.

Possible Side Effects

Neem supplements are likely safe for adults when taken orally for a short period, but they should not be used in children or pregnant women. There is not enough research to support its safety while breastfeeding.

While doses of up to 60 milligrams (mg) daily for up to 10 weeks have been safely used in human research, little is known about the safety of long-term use of neem supplements.

Since neem may increase activity in the immune system, it's crucial for people with autoimmune disorders such as multiple sclerosis, lupus, and rheumatoid arthritis to take caution when using neem. People who are taking immunosuppressants should not take neem unless under doctor supervision.

In addition, people taking diabetes medication should consult their physician prior to using neem. Because neem may reduce blood sugar levels, using it in combination with diabetes medications may cause blood sugar to drop to dangerously low levels.

Neem may have a negative interaction with lithium, altering the body's ability to metabolize the drug and could lead to dangerous interactions.

There's also some concern that neem may cause damage to the kidneys and liver, and may lower sperm counts.

Though rare, serious adverse reactions have been reported in both children and adults after swallowing neem oil. Neem is safe for topical use when diluted in other oils, topical preparations, lice treatments, and shampoos. However, it is not advisable to apply undiluted neem oil directly to the skin as it may cause irritation.

Selection, Preparation, & Storage

Widely available for purchase online, neem can also be found in many dietary supplement and natural-food stores in capsule, tincture, powder, oil, cream, shampoo, and mouthwash form.

The type of neem product you choose will depend on the reason you are using it (e.g., a cream for skin concerns vs. a mouthwash for dental issues). Neem oil should be diluted in a carrier oil, such as coconut or grapeseed oil, prior to applying it to skin.

There is no standard dosing for neem as there is not enough scientific evidence to support a recommendation. Follow the instructions on the product label.

Dietary supplements are not regulated by the U.S. Food & Drug Administration (FDA). To ensure you are purchasing a quality product look for a trusted independent, third-party seal on the label, such as U.S. Pharmacopeia, NSF International, or ConsumerLab.

Common Questions

Is neem an effective insect repellant?

When it comes to repelling mosquitos and other insects, neem oil works similarly to citronella. You can use it as an insect repellant by applying diluted neem oil to the skin, burning a neem candle or incense, or mixing neem oil with kerosene (in a 1:100 ratio) in an oil lamp or lantern. 

A 2015 study in Malaria Journal found a 20% neem formula is more than 70% effective against mosquitos and that the protection lasts about three hours. Researchers noted, however, that neem is not as effective as DEET in repelling mosquitos.

Does neem oil kill lice? 

Yes, in fact, there are a few anti-lice shampoos that contain neem oil on the market. One study found a 10-minute treatment with a neem-based product sufficiently killed lice and eggs.

As with other lice treatments, it is recommended to use a fine-tooth comb after rinsing hair and follow up with a second treatment if necessary. 

What types of hair are neem oil products recommended for? 

Shampoos, conditioners, hair oils, and similar haircare products containing neem are promoted for a wider variety of hair types. Neem medicated shampoos are recommended for people with dandruff or thinning hairlines.

People with curly or natural Black hair may find that neem oil conditioners and leave-in treatments help moisturize and tame frizz. Neem oil shampoos are also promoted for people with fine hair looking to increase volume.

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