**1. Introduction**

In 2016, more than 1.9 billion adults aged 18 years and older were overweight. Of these over 650 million adults were obese i.e. 39% of adults and over (39% of men and 40% of women) were overweight. Overall, about 13% of the world's adult population (11% of men and 15% of women) were obese in 2016. Obesity is quantities in terms of Body Mass Index (BMI), which is defined as the ratio of the weight and the square of height and is a measure of body adiposity [1]. The incidence and prevalence of

obesity, are rising both in developed and developing countries. Although globalization has resulted in substantial improvements in quality of life and food security, as well as reductions in poverty, unintended consequences of globalization are also driving the obesity epidemic. Among the multiple factors contributing to its etiology, the sedentary life styles, white collar jobs, lack of exercise, psychological factors, excess consumption of junk food and the consumption of energy rich diets are the major ones. Obesity is excessive accumulation of fat in the body associated with numerous complications such as development of hypertension, type 2 diabetes (T2DM), dyslipidemia, sleep apnea, and respiratory disorders; and ultimately life-threatening cardiovascular disease (CVD), stroke, certain types of cancer and osteoarthritis. Currently there is rapid rise in obesity and related severe diseases mainly due to drastic changes in lifestyle, living standard and modern diet. However rapid urbanization, economic revolution and free trade liberty are main reasons behind this. Nowadays in low and middle income nations there is drastic change in nutritional values mainly due to getting proteins and fats obtained from animals, added sugars and refined grains. Due to obscure etiology, the pharmacological treatment of obesity has been a particularly challenging task. Reducing body weight by lifestyle alteration is advisable, but sometimes drug intervention is necessary. Combating obesity is going to requires coordinated efforts from the international community, governments, industry, health-care systems, schools, urban planners, agriculture and service sectors, the media, communities and individuals. Further, the cause of concern is the non-availability of drugs for its treatment and the short-term efficacy and limiting side effects of the available drugs. Drugs used for obesity management are mainly classified in to metabolic promoters, digestion and absorption blockers, central appetite suppressants and obesity gene product inhibitors. However drugs used for obesity management specifically affects monoamine neurotransmitters leads to habit forming, dependence or abuse [2]. Anti-obesity drugs have been studied profoundly for decades. The need for adjunctive therapies for weight loss has accelerated the progress in the pharmaceutical industry worldwide. Weight loss drugs may appear to be a solution to obesity. However, possible side effects or adverse drug reactions are always a big public health concern and also a major barrier to the development of new drug products. Obesity, which is broadly refers to excess body fat, and ranked as the fifth foremost reason for death globally. Overweight and obesity are major lifestyle illness that leads to wide variety of chronic diseases, which may include cancers, metabolic syndrome, diabetes, cardiovascular diseases, osteoarthritis, gout, breathing problems etc. The World Health Organization predicted about 30% of death occurring in whole


### **Table 1.**

*Classification of weight based on body mass index.*

*Role of Leptin in Obesity Management: Current and Herbal Treatment DOI: http://dx.doi.org/10.5772/intechopen.105862*

world will be initiated with lifestyle disease in 2030 and can be stopped by appropriate identification and conveying associated risk factors. It is therefore essential to detect and diagnose obesity as early as possible [3]. Worldwide more than 1.9 billon adults are overweight and 650 million are obese. Approximately 2.8 million deaths are reported as a result of being overweight and obesity. This is major health related problem in both developed and developing countries. In India more than 135 million individuals were affected by obesity. The study of total body fat accurately requires sophisticated technology. The World Health Organization (WHO) have acquire body mass index, which is calculated by dividing the body weight in kilograms (kg) by the square of the height in meters (m), as a surrogate measure of total body fat (**Table 1**). With this index, obesity is defined when the value is equal to or more than 30 Kg/m<sup>2</sup> [4]. Formula: BMI = Weight/Height2 .
