Black jeera or black cumin, also known as Nigella Sativa, is a widely used traditional medicinal plants throughout the world. Its seeds and oils have been proved to be an effective treatment for many health issues such as weight loss.
The presence of active components such as polyphenols, thymoquinone, and phytosterols make black jeera an effective solution for weight loss. Black jeera helps to rectify the digestive system, reduces obesity, improves immunity, and lowers the blood cholesterol level.
Black jeera can be consumed in various forms such as powder, oil, or extract for weight loss.
Research has also been done to find out the efficacy of black jeera for weight loss. In a study, 50 overweight/obese women were investigated, and among them, 25 women were asked to consume 3 g/day Nigella Sativa oil for 8 weeks. At the end of the study, a decrease in body fat mass and insulin levels had been measured. 
In another study, 30-45 years old male divided into treatment and control groups and were evaluated for 3 weeks. At the end of the study, the treatment group male showed a significant reduction in body weight, waist circumference, and systolic blood pressure. 
How does Black Jeera Help in weight Loss?
Bad digestion means poor absorption of food and can lead to weight gain. Fiber has been proved to be a crucial ingredient for proper digestion.
One 5g of a tablespoon of black jeera contains 1g of dietary fiber. 
Fiber slows down digestion, which adds bulk to stool and improves bowel movement. Fiber is also associated with lowering body weight as it reduces the absorption of foods that increase the satiety. 
Obesity is a severe medical condition that can cause serious diseases such as diabetes, heart disease, and cancer.
Black jeera contains polyphenols such as alkaloids, terpenoids, and flavonoids which possess anti-inflammatory and anti-obesity characteristics. [5, 6]
In a study, the effect of black jeera on obesity investigated, and it has been found that supplementing with black jeera showed a reduction in body weight, BMI, and waist circumference. 
Lowers Cholesterol Level
Black jeera has a cholesterol-lowering effect. It is due to the presence of unsaturated fatty acids such as linoleic acid, oleic acid, eicosadienoic acid, and dihomo linolenic acid. The high content of these fatty acids results in decreased serum total cholesterol. 
Black jeera also contains high levels of phytosterols.  Consuming phytosterols in recommended quantities has been shown to lower total cholesterol up to 10 percent and LDL or “bad” cholesterol up to 14 percent. 
In a study, 57 patients with type-II diabetes showed that supplementing black jeera for one year decreased total and LDL cholesterol, while increased HDL cholesterol. 
Reduces Oxidative Stress
One study has proved that obesity leads to chronic oxidative stress, which, as a result, causes weight gain. Dietary antioxidant supplementation can be a beneficial remedy in reducing these harmful oxygen radicals which, as a result, can reduce the body weight or other obesity-related disorders. 
Black jeera oil has a bioactive component called “Thymoquinone,” which possesses antioxidant and anti-inflammatory properties.  The intake of black jeera can enhance the antioxidant capacity of the body. As a result, it reduces oxidative stress, which can lead to a reduction in body weight.
Our Immune system plays a vital role to protect the body from germs and other invaders. Excess fat alters how the immune system of our body react to these external invaders. Generally, obese people have a slow-reacting immune system.
In a research done by Dr. Lydia Lynch, Assistant Professor, Trinity College Dublin, discovered that a very normal immune cell called the invariant natural killer T cell (iNKT cell) plays a crucial role in regulating metabolism which as a result enhances weight loss.
This iNKT cell helps fat cells to make a small protein called fibroblast growth factor-21, (FGF-21), which triggers the body to metabolize or turn white fat into a much healthier brown fat. This browning of white fat uses large amounts of energy, leading to increased metabolic rate and weight loss.
In a study conducted by Dr. El-Kadi and Dr. Kandil found that black cumin showed an improvement in the immune system by increasing 72 percent in T-cell ratios and functional cell activity in most participants.
So, black jeera will help the body to produce iNKT cells to increase the amount of FGF-21. It, in turn, leads to an increase in browning of white fat, and an increase in metabolic rate and weight loss.
How to Consume Black Jeera for Weight Loss?
Toast a pinch of black jeera over curries or lentil dishes to add flavor.
Consume a mixture of 3 mg of black jeera, warm water, honey, and lemon.
Roast black jeera and grind to make a fine powder. Add the powder with honey, water, yogurt, or other food.
Take black jeera oil, add it to a salad or add the oil with a glass of water and mix honey to the water mixture to make it sweet.
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