Our modern world of today faces an epidemic of overweightness and obesity, which affects one third of the world’s population, and this ratio is on the rise. Generally, Body Mass Index (BMI) is a convenient indicator for categorization of overweightness and obesity in adults, which can be calculated by division of body mass (kg) by square of height (m) (kg/m2). According to the definition by World Health Organization (WHO), BMI≥25 is considered overweight and BMI ≥30 obese. In 2005, 1.6 billion individuals over 15 years of age were overweight and at least 400 million obese and at least 20 million children younger than 5 were overweight. Currently, overweightness and obesity is on the rise in low and middle-income countries.
The main cause of obesity and overweightness is an imbalance in caloric intake and output. Obesity can have dangerous consequences like cardiovascular diseases, diabetes, musculoskeletal disorders, especially osteoarthritis and some types of cancer, like cancers of endometrium, breast and colon.
To lose weight and treat obesity, several pharmacological and non-pharmacological treatments exist, none of which have definitive results. Based on the carried out researches, to lose weight and maintain it, also to physically improve the body and increase muscle mass without fat, substances extracted from citruses can be orally used in human. Also, to reduce or control weight, these substances can be used while simultaneously limiting calorie intake or not. The mechanism of action has been proposed to be thermogenesis (increase in rate of metabolism and facilitation of lipolysis) and hunger suppression, the latter being more evident with intake of larger doses and in individuals in whom active ingredients penetrate the Blood Brain Barrier more easily.
In a study of the effects of lime essential oil on weight loss, mice were administered either alone or simultaneous with ketotifen (an antihistamine which causes weight gain), over a period of 45 days, in comparison to the control group, in the mice receiving ketotifen, a rise in food intake and body weight was observed. The mice receiving lime essential oil showed weight loos, probably due to loss of appetite. The concomitant administration of ketotifen with lime essential oil considerably blocked weight gain and caused weight loss. Based on the results of this study, lime essential oil plays an important role in weight loss and can be beneficial in the treatment of weight gain due to drugs and diseases.
To evaluate the effects of daily use of zireh and limutorsh soft capsules on weight loss and metabolic profile of overweight individuals, in a controlled, randomized, double-blind clinical trial on 74 overweight individuals between 15-65 years of age, after a two-week run-in period, the patients were randomly divided into two groups to either take 75 mg zireh and limutorsh soft capsule (24 individuals), or 25 mg zireh and limutorsh soft capsule (24 individuals) or placebo (24 individuals). The patients were asked to take for 8 weeks either the drug or the placebo 2 times per day, with their lunch or dinner (zireh soft capsule half an hour before and lime soft capsule after their meal). Weight change and BMI were recorded in the three groups after the intervention. Biochemical measures were carried out before and after the intervention, including metabolic profiles, plasma Total Antioxidant Capacity (TAC) and total glutathione (GSH).
Based on the results of this study, at the end of the survey, in patients receiving the 75 mg dose, the 25 mg dose of zireh and limutorsh soft capsules and the placebo weight change was 2.1±1.7, 1.2±1.5 and 0.3±1.3 kg, and change in BMI was 0.8±0.6, 0.5±0.5 and 0.1±0.5 kg/m2, respectively. Changes in the both test groups were significant compared to the placebo group; however, the difference between the two test groups was almost significant. Furthermore, the use of 75 mg zireh and limutorsh pearls resulted in significant decrease in fasting blood sugar (-20.9±25.5 as opposed to -7.8±16.8 and 4.6±14.3 mg/dL, p<0.001), significant increase in insulin sensitivity (0.02±0.02 as opposed to 0.01±0.02 and 0.01±0.01, p=0.008), significant reduction in triglyceride levels (-14.1±56.2 as opposed to 13.9±36.8 and 10.6±25.1 mg/dL, p=0.03), total cholesterol (-18.4±28.6 as opposed to 8.6±28.5 and 1.0±24.8 mg/dL, p=0.004) and LDL cholesterol (11.8±20.7 as opposed to 6.5±23.2 and 2.9±20.4 mg/dL, p=0.01), in comparison with the 25 mg dose of zireh and limutorsh soft capsule and placebo. The researchers concluded that, on the whole, the use of 25 mg zireh and limutorsh pearl for 8 weeks has beneficial effects in weight reduction and the use of the 75 mg dose, apart from weight reduction, has a role in improving metabolic profiles in overweight individuals, compared to the control group.