RubmdSelf CareStart Improving Your Health with Benefits of Black Walnut Hulls

Start Improving Your Health with Benefits of Black Walnut Hulls

Black walnut hulls have been used for centuries as a traditional folk remedy to treat a variety of health conditions. Modern scientific research has now confirmed many of the health benefits this unassuming nut can provide.

Black walnuts come from the Black Walnut tree (Juglans nigra), which is native to Eastern North America. The tree produces a green fruit which consists of a fuzzy outer hull or shell which encloses the hard black walnut shell and the delicious nutmeat inside.

The hulls can be collected when they fall from the tree and are still green. At this stage they can be dried or used fresh. The dried hulls are very lightweight and have an earthy aroma. Fresh hulls have the highest concentration of active ingredients.

Traditional Medicinal Uses

Native Americans discovered many uses for black walnut hulls. They applied poultices of mashed hulls to skin irritations and infections to soothe and heal rashes, wounds, bites and inflammations.

Crushed hulls were also used to treat ringworm and as an anti-parasite to expel intestinal worms. Black walnut tea was drunk to treat diarrhea, dysentery, sore throats and tonsillitis.

Early American settlers quickly learned of the healing powers of black walnut hulls from the Native people and used them similarly. Over the years, herbalists continued applying hulls for all kinds of skin maladies and to maintain overall wellness.

Modern science has shown us that black walnut hulls are rich in beneficial anti-inflammatory, antioxidant and anti-microbial compounds. Let’s take a look at some of these key components.

Key Compounds and Benefits


Black walnut hulls contain juglone, a chemical that is considered an organic herbicide. Juglone exerts an inhibitory effect on certain enzymes needed for metabolic function. It affects plants through a process called allelopathy, acting as a chemical messenger between plants that alters the growth of nearby plants.

While high levels of juglone can be detrimental to some plants, small amounts have beneficial health effects in humans. Research has shown juglone has antitumor, antimicrobial, insecticidal and parasiticidal properties.


The hulls are rich sources of antioxidants including flavonoids, phenolic acids and naphthoquinones. These help rid the body of damaging free radicals and reactive oxygen species that can lead to cell damage. The high antioxidant content means black walnut hull extracts can preserve foods and cosmetics naturally.

Anti-inflammatory Compounds

Black walnut hulls contain numerous anti-inflammatory compounds such as ellagic acid, gallic acid, syringic acid and myricetin. These reduce inflammation at cellular and organ levels which helps treat inflammatory conditions in the body.

Antimicrobial Activity

Studies have documented the broad spectrum antimicrobial capacities of black walnut hulls. The extract has been shown effective against gram-positive and gram-negative bacteria, yeasts, fungi such as Candida albicans and even cancer cells. Researchers believe compounds like juglone, tannins and phenols contribute to it’s antimicrobial effects.

This powerful antimicrobial activity supports the traditional uses of black walnut hull preparations for treating skin conditions, wounds, ulcers and infections.

Scientifically Proven Health Benefits

Decades of anecdotal evidence along with multiple scientific studies have confirmed key health benefits of compounds found in black walnut hull extracts:

1. Skin Conditions

Black walnut hull preparations help treat common skin conditions including acne, warts, psoriasis, eczema and herpes sores. The high levels of antioxidants reduce free radical damage to skin cells. Anti-inflammatories ease swelling and redness. Antimicrobial compounds curb infection causing bacteria and fungi living on the skin.

Applying black walnut hull tincture or oil helps heal cold sores from herpes simplex, soothe psoriasis and relieve diaper rash. The mighty juglone targets human papilloma virus helping heal stubborn warts. Those with acne report reduced breakouts with continued use. Even minor cuts and scrapes heal faster.

2. Intestinal Problems

A time tested remedy for all manner of intestinal troubles, black walnut hull preparations help treat constipation, diarrhea, parasites, colitis and inflammatory bowel diseases.

As a gentle laxative, black walnut hull tea lubricates the intestines to relive mild constipation. It acts as an astringent shrinking inflamed tissues to alleviate colitis symptoms of bleeding, mucus, abdominal tenderness andfrequent bowel movements. The high levels of antioxidants reduce free radical damage from inflammation in the gastrointestinal system.

Juglone, tannins and phenols act to expel parasites from the digestive tract by altering the site where parasites attach to gut mucosa. They literally crowd out and starve unwanted guests like worms!

3. Oral Health

Due to powerful antimicrobial effects, black walnut hull extracts help treat oral infections, inflammations and dental plaque formation. Rinsing the mouth with diluted black walnut extract combats bacteria colonies forming on teeth and gums to prevent cavities, gingivitis and periodontal disease. Using black walnut tooth powder instead of regular toothpaste leads to fewer oral health problems.

4. Cancer Fighting Properties

Black walnut hull preparations show promising anticancer abilities. Lab studies found breast cancer, leukemia, ovarian cancer and melanoma cells died after treatment with juglone. The compound inhibits the metabolic enzymes these cancer cells need to multiply while also activating the body’s natural tumor suppressors.

The phenolic compounds halt creation of vessels tumors require to grow. Ellagic acid induces cell apoptosis or natural cell death in malignant cells. More research is underway exploring applications for cancer prevention and treatment.

5. Improved Heart Health

The antioxidants in black walnut extract help cardiovascular health by preventing LDL cholesterol oxidation which leads to dangerous plaque formation in artery walls. This lowers risk for atherosclerosis and heart disease.

6. Candida Infections

Candida albicans overgrowth causes a condition called Candidiasis resulting in symptoms like chronic fatigue, digestion issues, yeast infections, brain fog and nutrient deficiencies. Black walnut extracts have been shown in lab research to inhibit candida growth very effectively. The supplement is considered a prominent natural anti-fungal treatment.

7. Diabetes Management

There is some evidence black walnut leaf and hull extracts may alleviate diabetic symptoms. One study showed walnut leaf tea enhanced glycolysis helping regulate blood sugar levels in diabetic rats. More research is needed to confirm benefits for human diabetestreatment.

8. Anti-aging Effects

The antioxidant content combats free radical damage to cells and tissues which slows the aging process. Using black walnut kernel oil on wrinkles and age spots helps diminish their appearance over time.

9. Weight Loss

Some herbalists recommend using black walnut tincture to promote weight loss though minimal research exists to support this benefit. It’s thought juglone may alter gut flora populations increasing beneficial bacteria like lactobacilli while suppressing undesirable bacteria which could enhance weight loss efforts.

Again, current data doesn’t conclusively support weight loss claims. But black walnut extracts have relatively few side effects so they may help boost a healthy diet and exercise program.

As research continues, more benefits of black walnut hull components will likely emerge. Let’s learn how to prepare them for use.

How to Prepare and Use Black Walnut Hulls

There are several ways to prepare black walnuts hulls:

Dry and Crush – Allow fresh hulls to dry completely then grind into a powder to use internally or as a poultice mixed with herbs or clay.

Tincture – Soak fresh hulls in alcohol like vodka for several weeks then strain through cheesecloth creating a potent beneficial tincture

Oil Infusion – Allow hull pieces to slowly infuse into oil for topical skin application

Tea – Boil dried hulls and leaves then strain to drink as a therapeutic beverage

Powdered Supplements – Take encapsulated dry hull powder in pills daily

For internal preparations such as tincture or tea, dried organic hulls are preferred rather than fresh hulls to avoid higher levels of juglone which may cause stomach upset in some people.

Externally, crushed or cut fresh hulls work well for skin poultices and compresses. Some people react to topical application due to skin sensitivity so do a patch test first.

Dosage depends greatly on the type and concentration of preparation used. With teas, several cups can be drunk daily. Extract potency means tinctures use smaller doses, from several drops up to a full dropper. Hull powder is taken in 500-1000 milligram amounts twice daily. It’s best to follow manufacturer or herbalist instructions for topical applications and oral supplements until you know how you respond personally.

Possible Side Effects and Considerations

Black walnut hull remedies are considered very safe with minimal risk of side effects though some things to consider:

  • Pregnant or nursing women should avoid black walnut remedies internally since juglone may have effects on hormones and fetal development. External applications to the skin when pregnant should happen only under guidance of a professional herbalist.
  • Allergy is possible though fairly uncommon. Discontinue use if signs of allergy develop such as rash, hives, itching, swelling or difficulty breathing.
  • Juglone may interact with some medications so check with your doctor or pharmacist about potential interactions, especially with blood thinners, blood pressure and thyroid drugs.
  • Don’t apply black walnut oil or tincture directly to skin anywhere juglone could enter or irritate mucus membranes of eyes, nose or genitals.
  • Internal doses of teas and extracts may cause mild laxative effects like stomach cramps or diarrhea though this typically improves with smaller doses taken with food.

As with any herbal supplements, consult your healthcare provider before beginning a black walnut regimen if you have health conditions or take medications to prevent complications. While relatively gentle, watch for any worrisome reactions.

How to Harvest Your Own Black Walnut Hulls

You can easily harvest black walnuts yourself each season. Here’s a simple DIY guide:

When – Harvest time depends somewhat on your region but typically falls between August and October after summer rains when hulls turn from green to brown or black. Test a few first by trying to penetrate the hull with your thumbnail. If it easily cuts in, the hull is ready for harvest. Gather too early and the hull won’t be mature. Wait too long and they may start to rot or sprout if the weather is wet.

Gathering Tools – Nuts fall quite high from mature trees. You’ll need gloves to avoid hull plant juices from staining fingers. Use a hard rake to gather hulls from the ground and long branch clippers secured to an extended pole to clip higher branches holding hull clusters if needed.

Cleaning Tips – Expect lots of slippery crushed hull pieces. Avoid stepping on them! Remove debris like twigs then lay hulls on screens or newspaper to air dry for a week or two until properly crisp and lightweight. Discard any molded bits.

Storage – Fully dried black walnut hulls keep for up to a year stored in burlap bags or cardboard boxes out of direct sun in a garage or shed. Check periodically and discard any hulls or pieces developing mold.

Now enjoy your homemade black walnut remedies! They provide powerful immune boosting antioxidants to support whole body wellness.


What do black walnut hulls taste like?

Black walnut hulls have an earthy, bittersweet flavor. The dried hull powder can be added to foods or drinks as a supplement, but is generally too bitter to consume directly. Tinctures made from the hulls tend to extract more bitterness during the alcohol infusion process.

Where can I buy black walnut hulls?

You can purchase dried black walnut hulls, hull powder and hull tincture online or at many health food stores and vitamin retailers. Make sure you buy from a reputable supplier that doesn’t use pesticides. You can also harvest and dry your own hulls if you have access to black walnut trees.

What’s the difference between black walnut hulls and leaves?

The hull refers to the green outer covering of the black walnut nut itself. This is the part most commonly used medicinally. The leaves come from the elongated pinnate leaves of the tree. While the leaves have some similar properties and uses to the hulls, they tend to be milder in effect.

Are black walnut hulls safe for dogs?

In small quantities, dried black walnut hull powder can act as a natural dewormer for dogs. However dogs should not consume excessive amounts of hulls or hull tincture due to the juglone content which may cause drooling, vomiting, weakness and tremors at high doses. Always check with your vet before using.

Can black walnut hulls stain skin?

Yes, fresh and dried hulls contain juices that may temporarily stain skin a brownish-purple color. Hull preparations also have the potential to stain clothing and countertops. The good news is walnut hull stains generally fade and disappear from skin and surfaces over time. Scrubbing hands and using gloves when handling fresh hulls can prevent staining.


Black walnut trees grow across North America dropping their medicinal gifts yearly. These unassuming green fruits encase health-enhancing compounds rivaling the most potent tropic superfoods or expensive supplements. Their practical antiviral, anti-fungal, antioxidant and anti-inflammatory effects heal skin, treat parasites, soothe IBS, inhibit cancers and enhance oral health.

Traditional herbalists, indigenous peoples, historical communities and now doctors recognize black walnut’s mighty benefits. Modern science continues confirming traditional applications work with clinically proven results on par with pharmaceuticals but with virtually no side effects.

Safe, sustainable and simple to use at home, black walnut hull remedies deserve a prime spot in our natural medicine cabinets. Harness their gifts through easy to make teas, tinctures, oils and skin creams. Or just chatter them onto your garden beds so no part goes to waste. However you use them, you’ll soon discover the legendary healing power found in black walnut’s humble hulls.

Team RubMD
Team RubMD
RubMD Team is committed to providing reliable and trustworthy information on healthcare-related topics to our readers. We strive to maintain the highest standards of accuracy, professionalism, and ethical conduct in all our content.

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