Dating back to the time of the ancient Egyptians, Nigella sativa (commonly referred to as black seed or black cumin seed) has tremendous historical significance and therapeutic potential. Mentioned in the Old Testament and by the Prophet Muhammad, black seed has been used so broadly around the world that it is considered as a panacea in many cultures. Scientists in the last few decades have investigated the potential health benefits of this herb and have corroborated may of its traditional benefits.

Several active constituents have been identified in black seeds, including thymoquinone and nigellone. Studies looking at the active compounds have shown that they possess antioxidant and anti-inflammatory benefits and play a key role in modulating immune function. Additional studies have found that black seed oil benefits the respiratory tract and seasonal allergies, gut health, liver function, and heart health among its many effects.

Respiratory System

Black seed and its constituents act as potent inhibitors of histamine and as smooth muscle relaxants, which makes it beneficial for acute and chronic lung and sinus conditions. Histamine is a key trigger for allergy symptoms and research on nigellone from black seeds shows that it has powerful antihistamine effects. Nigellone prevents the release of histamine from mast cells of the immune system, resulting in inhibition of allergic reactions.

Another beneficial effect of black seed is that it acts as a muscle relaxant, which makes it an effective bronchodilator, allowing airways to relax and stay open. This is particularly effective for asthma and other lung conditions. Thymoquinone has shown bronchodilator effects multiple research studies, and randomized controlled trials in people with asthma showed that even a single dose of black seed extract led to a significant improvement in open airways.

Studies in humans with black seed have shown that the herb has significant potential in treating allergic rhinitis as well as asthma. For allergic rhinitis, studies have used black seeds for its treatment and prevention. Symptomatic improvement in individuals suffering with this condition included reductions in red, watery eyes, nasal congestion, runny nose, sneezing and itching. This is likely because of black seed’s antihistamine and anti-inflammatory actions.

Similar benefits have been shown in trials with asthmatics supplementing with black seeds. Individuals taking black seed extracts showed improvement in the clinical symptoms associated with asthma as well as in lung function tests. Bronchodilator effects (keeping airways open) were also seen in some studies, leading to improved ability to breathe effortlessly. Other investigators noted reduced inflammation in the lungs as well as improvements in forced expiratory volume (FEV1), a measure of the ability to breathe out with ease. These studies highlight the tonifying benefits of black seed oil for respiratory system function.

Digestive Tract, Gut Health

Traditional use of black seed and its oil include the treatment of conditions affecting the digestive tract and gut health. Specifically, this has been the case in both Ayurvedic and Unani medicine in the Indian subcontinent as well as the Middle East. Research has found that many constituents of black seed possess beneficial qualities that make it useful for treating digestive health conditions. Thymoquinone, in particular, has several benefits for gut health.

Preclinical trials have evaluated the effect of thymoquinone on cells of the colon and have found that administering thymoquinone to these cells leads to healthier cellular function and protects them from being destroyed or undergoing programmed cell death. Further studies indicate that thymoquinone has beneficial properties on the microbiome, bringing bad bacteria into a healthy balance through antimicrobial effects. This reduces their viability and gives more space for beneficial bacteria to flourish, leading to the production of metabolic byproducts that benefit the health of the gut. Black seed oil further helps support digestive tract health through antioxidant and anti-inflammatory effects, reducing inflammation and free radicals that can damage the gastrointestinal tract.

The traditional use of black seeds extends to its beneficial effect on functional dyspepsia, a common gut health condition of the upper GI tract in which individuals suffer from abdominal pain, bloating, belching and nausea as its main symptoms. A causative factor in functional dyspepsia may include the overgrowth of the bacteria H. pylori. A clinical trial evaluated the use of a preparation of black seed mixed with honey in individuals with functional dyspepsia and found that those taking the black seed preparation had significantly decreased symptom scores as well as a lower rate of H. pylori infection after eight weeks, compared to the placebo group.

Kidney and Liver Function

Many of the constituents of black seed have been studied for their role in supporting the body’s detoxification process. Major organs that contribute to detoxifying chemicals and toxic metabolic byproducts include the liver and kidneys. Black seeds have been traditionally used as supporters of detoxification and clinical studies support this beneficial effect of the extracts.

A meta-analysis and review of clinical trials published in 2021 looked at the effects of black seed extract on a common condition in many individuals consuming processed foods and a westernized diet, non-alcoholic fatty liver disease. This condition is characterized by the infiltration of fatty deposits in the liver as a result of the liver being unable to process the excess fat and sugar that is consumed as a result of processed foods and sugars in the diet. The authors conducted an analysis of several published clinical trials using black seed extract and found that the extract led to improvements in several liver enzyme levels, indicating that liver function was improved by black seed extracts. Furthermore, inflammation decreased as measured by C-reactive protein (CRP) levels, and improvements were seen including higher levels of HDL (beneficial) cholesterol and decreased fasting blood sugar levels. Fatty deposits in the liver of those supplementing with black seed extracts were reduced significantly compared to those in the placebo group.

Thymoquinone from black seed oil has also been found to benefit kidney function in those with chronic kidney disease. A recent review article highlights the beneficial effects on kidney function seen in research studies. The authors summarized data from preclinical trials and found that thymoquinone protected the kidneys against injury caused by heavy metals, pesticides, and other environmental toxins found in foods we eat and the air we breathe. Clinical trials on black seed in chronic kidney disease participants also showed its ability to normalize blood and urine measures of kidney health and improve disease outcomes, indicating its beneficial effects for kidney.

Since it supports both liver function and kidney health, black seed extract has the potential to be of major benefit for overall detoxification.

Cardiovascular System, Heart Health

Black seed extracts have also been used as tonics for heart health. Containing the actives thymoquinone and nigellone along with essential fatty acids, black seeds play an important role in supporting heart function through antioxidant, anti-inflammatory and cholesterol balancing properties. Clinical trials show that black seed oil and extracts can reduce unhealthy cholesterol, support higher levels of HDL (healthy) cholesterol, and normalize blood pressure levels. In one double-blind, placebo-controlled clinical study, women were supplemented with black seed oil daily for eight weeks and showed significant increases in HDL cholesterol and reductions in LDL, as well as healthier total cholesterol levels. Systolic blood pressure was also significantly reduced in these women, while diastolic blood pressure remained unchanged.

A second study looked at the heart health impact of supplementation with black seed oil in those with type 2 diabetes. This one-year long placebo-controlled trial found that those supplemented with black seed oil had significant decreases in total cholesterol and LDL cholesterol levels, while protective HDL cholesterol levels were significantly increased. Further improvements were found as well, as both systolic and diastolic blood pressure levels decreased, as did mean arterial pressure and heart rate, compared to the placebo group, indicating broad benefits for the cardiovascular system and heart health with black seed supplementation.

With increasing research in the area and an ever-increasing burden of heart disease in our society, black seed is becoming a beneficial tonifier of the cardiovascular system.

Immune System Support

Black seed oil exerts powerful immune benefits by supporting both arms of the immune system, including innate and adaptive immunity. In a clinical study, the administration of black seed powder for 4 weeks led to significant improvements in immune function. The ratio of CD4+/CD8+ T cells significantly improved and an increase in natural killer cell function was also seen.

In animals whose immunity was suppressed by experimental measures, giving them black seed led to a restoration of immune function back to normal levels. An additional study in animals whose immune systems were chemically compromised showed that black seed oil administration decreased antibody responses and the levels of complement C3, supporting an immune regulatory role of the extract, indicating balanced immune function.

As a miracle herb that has been used as a panacea for millennia in multiple cultures, black seed oil benefits are being elevated from the realm of traditional use to modern science. As researchers continue to study this herb and its constituents, the usefulness of this traditional tonic for respiratory, immune, digestive, heart, liver, and kidney function is becoming clearer. Incorporating black seed supplements into your daily regimen is a smart move to support overall health.

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