Black Seed

The black seeds of the Nigella sativa plant are quite possibly the most famous seeds you’ve never heard of. Believed to have originated in the area spanning the eastern Mediterranean to India, N. sativa played, and continues to play, an important role in the traditional medicine of every culture with access to it. It was found in King Tut’s tomb, mentioned in the Hebrew bible, and the Prophet Mohamed is reputed to have said it was a cure for everything, except death.1 N. sativa is part of the Ranunculaceae family (the same family as columbines, buttercups and goldenseal) and grows up to 35 inches with pale-blue to pale-purple flowers that contain the valued black seeds. In the United States, it is most frequently called black seed, but sometimes black cumin or black caraway, due to a similar appearance, not an actual relation to these plants.

Traditional Uses

Black seeds are valued as a spice and preservative, used to flavor yogurt, pickles, sauces, salads, baked good and cheese.2 As a medicine they were traditionally used for disorders of the respiratory system, digestive system, kidneys, liver, cardiovascular system and immune system.3 The seeds are said to “stimulate the body’s energy and [aid] recovery from fatigue and dispiritedness.”3 Black seeds were used internally to treat loss of appetite, indigestion, diarrhea, menstrual irregularities, and swelling, and the oil was used topically to treat a number of skin conditions.3 Black seeds are also taken with honey according to traditional Arabic and Islamic medicine.1

Composition

Black seeds are a good source of fiber and high in unsaturated fats, in particular the omega-6 fat linoleic acid and the omega-9 fat, oleic acid, the fatty acid olive oil is valued for.4 The seeds also contain various vitamins and minerals as well as numerous chemical compounds. It is the plant compounds that are largely believed to be responsible for black seed’s medicinal activities. The most researched of these compounds is thymoquinone, but other active compounds are likely to also be valuable, including thymohydroquinone, dithmoquinone, p-cymene, thymol (the same compound found in thyme) and carvacrol (also found in oregano).4

Modern Research and Uses

Black seed is still used today in traditional Arabic, Islamic and Indian medicine for flatulence, asthma, headaches and migraines, joint pain and lower back pain, vitiligo, and a variety of skin conditions.1 Research has confirmed many of these traditional uses and in some cases offered insight into the mechanisms behind the actions. We now know that black seed acts as a free radical scavenger, modulates inflammation, increases cerebral blood flow, interacts with neurotransmitters and induces apoptosis.5 6 7 

Anti-microbial

Although human studies are lacking, in vitro and animal studies support black seed’s traditional use as an antimicrobial. Black seed is effective against a variety of gram-negative and gram-positive bacteria, the fungus Candida albicans, and some parasites. Black seed may even exert antiviral effects by supporting the response of the body’s own natural immune cells and through its antioxidant properties.8

Asthma

In several small human studies, black seeds improved several markers of asthma, including improved pulmonary function and normalization of blood markers. In these studies, the effect of black seed was significant when compared to placebo, but generally was not as effective as prescription medications.9 10 11 12 13 Several of these studies used a boiled extract of the black seeds, a traditional Iranian method of preparation. 

Bone Health

Through its antioxidant and anti-inflammatory properties, black seed and/or thymoquinone may exert positive effects on the health and strength of the bones. In animal studies, black seed oil was found to reverse diabetes-induced bone changes and improve healing in non-osteoporotic bone fractures.14

Cancer

Thymoquinone and some of black seed’s other compounds induce apoptosis, act as both antioxidants and pro-oxidants, interfere with signaling pathways, modulate the immune response and reduce metastasis—all actions that are anti-cancer. In vitro black seed has been shown to exhibit several anti-cancer activities against a myriad of human cancer cells including myeloblastic leukemia, breast cancer, colon, some pancreatic cancer cells, hepatic cancer cells, prostate and cervical cancer cells.7 It also appears that the actions of black seed don’t interfere with conventional chemotherapeutic drugs and may even enhance the effects of some.33 As promising as all this sounds it is important to remember that promising, not proven, is exactly what it is. To date there are no human studies and barely any animal studies to speak of. We are still quite a way from any real understanding of how black seed might help humans with cancer. Remember, cancer is an extremely complex, multi-factorial disease and should be treated under the guidance of trained professionals.

Cardiovascular Health

Black seed appears to support healthy blood lipid levels, in particular total cholesterol, LDL cholesterol and triglycerides.15 16 17 18 The effects of black seed on HDL cholesterol have been mixed, with some research showing improvement and others no change. There is also some evidence to suggest that black seed might support healthy endothelial function and healthy blood pressure.19 30 20 21 22

Digestive Support

Besides being long recognized as a carminative herb (one that is capable of dispelling intestinal gas), black seed also appears to protect the mucosal lining, modulate inflammation, and act as a free radical scavenger in the gastrointestinal tract.23 Two small human studies suggest that black seed (when combined with a proton-pump inhibitor) may be an effective therapy for eradicating H. pylori and may reduce pain and symptoms associated with gastroesophageal reflux disease (GERD).24 25

Liver Health

In one small human study, patients with Non-Alcoholic Fatty Liver Disease taking black seed for two months saw improvements in their body mass indexes, liver enzymes, and a regression of fatty liver.26 Black seed was also protective against changes induced by binge-drinking in mice.27  

Memory and Cognition

Black seed may be neuroprotective and appears to improve cerebral blood flow, supporting healthy cognition and memory.28 6 In one small study, elderly volunteers who took 500 mg of black seed daily for nine weeks had improvements in memory, attention and cognition compared with the placebo group.29

Metabolic Syndrome

In rats fed a high fructose diet to induce metabolic syndrome, the co-administration of black seed prevented elevations in blood sugar, cholesterol, triglycerides, and blood pressure, while improving markers of oxidative stress.30 31 In one study, humans with metabolic syndrome who took black seed for eight weeks had improved blood lipids and fasting blood glucose, but when combined with turmeric, the improvements were greater than those achieved by either herb alone.32

Pain

In animal studies, black seed has shown an analgesic effect and it has been hypothesized that the effect might be due to the fact that thymoquinone is anti-inflammatory, modulates the immune response and is an antioxidant.33 34 35 In human studies, black seed oil has improved systemic markers of inflammation and led to reductions in pain and the need for over-the-counter medication.36 37 38 39 Black seed oil applied topically reduced knee arthritis in elderly patients and cyclical breast pain in women.40 41 An interesting place where black seed may prove to be beneficial is in opioid withdrawal. Black seed may inhibit tolerance and reduce dependence of opioids, possibly by blocking nitric oxide overproduction and the oxidative stress induced by these drugs.42 43 44 45

Skin Health

Black seed oil has a long history of use topically for skin conditions. Many of its known activities could contribute to its effectiveness topically including the fact that it is anti-inflammatory, analgesic, and antimicrobial. Several small human studies have found black seed oil to be an effective topical treatment for eczema, psoriasis, acne, and burns.46 47 48 49 50 51 52 Black seed oil emulsified with borage oil helped to reduce skin irritation and improve skin hydration and function.53 It should be noted that there are documented instances of black seed oil causing dermatitis when applied topically, and although this seems to be a rare side effect, it is always a good idea to test a small patch of skin with any new topical product (including those containing black seed) before applying to larger areas of skin.

Sleep and Stress

In a recent study, 15 subjects with significant sleep problems took 200 mg of black seed oil for 28 days. Benefits included improved sleep quality; sleep latency, measured by the total time it took subjects to fall asleep; and enhanced time of deep sleep. Additionally, subjects saw significant improvements in REM and non-REM sleep, both of which are a necessary part of a healthy sleep cycle. As a secondary measure, black seed oil was also found to reduce stress and anxiety scores in subjects at the end of the 28-day study.54

How to Take Black Seed

With so many different common names, it is important to ensure you are getting black seed by looking for products that clearly identify themselves by the Latin name Nigella sativa. Both traditionally and in research, black seeds have been used in many different forms, including as a tea, ground seeds in capsules, alcohol extract, a fixed (a.k.a. pressed) oil, an essential oil and of course added to foods whole.

For most applications a standard dose is 500-1,000 milligrams (mg) of crude black seed powder or fixed oil three times a day or for alcohol tinctures 3-5 milliliters (mL) three times a day.55

Some studies have seen a magnified effect when used in conjunction with turmeric.30 32

Safety

Black seed has an excellent safety record both through a long history of use and also through animal and human studies. Even still, side effects can occur. Potential side effects reported include nausea, bloating, heartburn and slight increases in liver and kidney enzyme markers, which tend to be mild and are relieved by discontinuing the black seed.56 Despite black seed being a relatively safe herb, caution should always be used when starting any new herb, nutrient or medication, especially if you are already taking other supplements or medications or have a medical condition.

References


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