Body weight management is a complex physiological event that depends upon gastrointestinal functioning, hunger or appetite management, as well as emotion and stress level management. 
The environmental alteration and workload variation affect our body weight. Most of us are health conscious and worried about body weight management. Appropriate body weight maintenance is one of the major factors for survival.
Maintenance of stable body weight depends upon balancing of energy intake and energy expenditure. This energy homeostasis can be sustained by proper consumption of nutrition and performing regular physical activity. The regulation of body weight is based on adipose tissue mass management.  The body mass index (BMI) is the tool available for assessment of adiposity. 
Being overweight and underweight are both harmful for healthy living. We are always in search of different health supplements to compensate our physiological need and try to shape up our muscle mass.
Nature has a miracle ingredient known as ‘Black seed’ rather popularly known as Blessed seed, as it offers multiple health benefits. The oil extracted from this seed acts as a remarkable weight regulator. It is a natural customized herbal remedy, which possess both weight loss and weight gaining properties and exerts its effect depending upon the need of an individual.
Black Seed Oil for Weight Loss
Obesity is one of the chronic conditions, which is associated with multiple co-morbidities, such as diabetes, chronic heart failure, thyroid hormone imbalance, arthritis etc. Obesity is directly linked with overweight or uncontrolled weight gain.
Different research studies performed to check the traditional use of black seed oil to determine its anti-obesity effect.
The Journal of Ethnopharmacology mentioned that black seed has mild anorexic (appetite suppressing) effect. 
An animal study showed that 4 weeks continuous consumption of black seed formulation can cause 25% appetite reduction and resultant of this can cause weight reduction. 
Several scientific literature published on the basis of human and animal study reports has also supported that black seed oil has significant effect in weight reduction, and imparts waist and hip circumferences lowering effect. Moreover, black seed oil has effect against elevated levels of fasting blood sugar, triglycerides, and low-density lipoprotein (LDL) levels. Therefore, the benefit of Black seed oil is not only limited in weight reduction but also shows its effect in controlling obesity associated co-morbidity through acceptance of black seed oil in our daily life. 
In males, one of the reasons for the increased rate of obesity is due to reduction in serum free testosterone. Human study results showed that daily consumption of black seed oil has potential benefit in enhancement of the serum free testosterone level and can significantly reduce body weight, waist circumference, and systolic blood pressure in obese male individuals. 
Researchers also assume that the black seed oil has the ability to recover glucose tolerance, improve liver health, diminish inflammation, and control glucose levels. Altogether, these activities assist our body to recover to a normal weight. 
It has also been found that emotional stress and depression can increase, as well as decrease appetite.  Hence, it is very important to have proper psychological balance to maintain weight regulation. Black seed has potentiality to stimulate energy balancing and provide feeling of well-being which further prevents the buildup of psychological stress and depression.  Therefore, black seed can also act as a weight regulator by maintaining mental health.
Black Seed Oil for Weight Gain
Often, underweight children and adults are treated with ‘appetite stimulant’ to increase their hunger. The bitter property of the black seed oil is utilized as ‘appetite stimulating’ effect and also promotes digestion. 
Thus, black seed oil can be effective for individuals who are unable to take adequate amount of food due to suppressed hunger because of digestive disorder or other causes.
Sufficient food intake is not only required for gaining weight, but for maintaining energy level to perform daily activity with full enthusiasm. Asian Pacific Journal of Tropical Biomedicine published a review article mentioning that black seed oil has therapeutic potential as ‘appetite stimulant’. 
Animal research study showed that black seed oil treatment can reduce body weight loss and control the factors like diarrhea, vomiting which significantly reduce body weight effectively by black seed oil treatment. [4, 5]
Dose, Direction & Precaution
The dose of any herbal medicine should be taken under consultation from expert therapist. However, according to the reported documents, the standard dose varies from 1 to 3 tablespoons daily depending upon the individual need.  In case of capsule, or other solid dosage form, 250-1000 mg is the recommended daily dosage. 
In case of inconvenience to take black seed oil directly due to its unpleasant taste, mixing it with one teaspoonful honey or a little cinnamon and water can be of help to make it more palatable. 
Some precautionary measures need to be followed. For example, individuals already in anti-diabetic, hypertensive medication therapy or herbal treatment need a proper dose adjustment, as hypoglycemia or hypotensive symptoms like dizziness, confusion, palpitation etc., can be developed due to additive effect of black seed oil and co-administrative drug effects. 
Use of black seed oil is cost worthy, as it not only acts as weight regulator, but it also maintains optimal health by managing weight. However, it is required to mention that black seed oil supplementation along with physical exercise can provide a perceptible weight
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- Shirin Hasani-Ranjbar, Zahra Jouyandeh, Mohammad Abdollahi; A systematic review of anti-obesity medicinal plants – an update; J Diabetes MetabDisord.2013; 12: 28. Published online 2013 Jun 19. doi: 10.1186/2251-6581-12-28; Retrieve from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3691594/
- A. Datau, Wardhana, Eko E. Surachmanto, K. Pandelaki, J.A. Langi, Fias; Efficacy of Nigella Sativa on Serum Free Testosterone and Metabolic Disturbances in Central Obese Male; Acta Med Indones-Indones J Intern Med; Vol 42, Number 3, July 2010; Retrieve from http://www.inaactamedica.org/archives/2010/20724766.pdf
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