Background: In Mongolian Traditional Medicine (MTM), the human body constitution is classified according to the doctrine of Khii, Shar, and Badgan, resulting in seven types: three single constitutions Khii, Shar, Badgan, three mixed constitutions Khii-Badgan, Shar-Badgan, Khii-Shar, and one combined constitution in which all three principles coexist. This concept considers not only physical, physiological, mental, and behavioral characteristics but also environmental influences. Childhood obesity has become a major global public health issue. In Mongolia, the prevalence of overweight and obese children aged 5–19 years is projected to reach 19% (approximately 79,648 children) by 2030. However, limited research has examined the relationship between children’s constitutional types and their physical and body composition indicators. Aim: Children (11-17 ages) innate nature of and study of the relationship between physical and body composition. Materials and Methods: A cross-sectional analytical study was conducted among 459 students aged 11–17 years from “Erdmiin Khutuch” Secondary School No. 58, Sukhbaatar District, Ulaanbaatar, selected through random sampling. Constitutional types were determined using the “Mongolian Traditional Medicine Human innate nature Typology” developed by B. Dagvatsereen and U. Batchimeg (2003), based on 19 parameters and 44 indicators through a web-based tool (WEB1). Body composition was measured using a Tanita DC430a analyzer. Statistical analyses were performed using SPSS version 27. Results: Among children aged 11-13 years, the predominant constitutional types were Badgan-Shar, Khii-Badgan, Khii- Shar, Badgan-Khii, and Shar-Khii, with Badgan-Khii being the most common. In those aged 14-17 years, the dominant constitutions shifted to Shar–Khii, Khii–Shar, and Shar–Badgan, with Shar–Khii and Khii–Shar more frequently observed. These patterns may be related to the physiological characteristics of growth during childhood and adolescence. The average height of boys was 158.35±1.13 cm (118-175), while that of girls was 154.94±0.61 cm (116-175), indicating that boys were 3.41 cm taller than girls (p<0.05). The mean waist circumference of boys was 69.66±0.79 cm (60-110), compared to 67.77±0.66 cm (29.50-108) in girls, showing a statistically significant difference of 1.89 cm (p<0.05). The findings demonstrated that girls had higher body fat percentage and fat mass than boys, whereas boys exhibited greater skeletal muscle percentage, skeletal mass, muscle percentage, and muscle mass. These sex differences in fat and muscle composition among children aged 11-17 years may be attributable to hormonal variations associated with pubertal development. Body mass index, waist circumference, body fat percentage, visceral fat level, daily metabolic expenditure, obesity grade, and bone mass showed a weak inverse correlation with the Khii–Shar and Shar–Khii constitutional types. Conclusions 1. Among children aged 11-13 years, Badgan-Shar, Khii-Badgan, Badgan-Khii, and Shar-Khii constitutions were dominant, while in those aged 14-17 years, Shar-Khii, Khii-Shar, and Shar-Badgan types predominated. 2. When comparing children’s physical indicators by sex, boys have greater height and waist circumference than girls. Regarding body composition, girls show higher body fat percentage and fat mass, whereas boys have greater skeletal muscle mass, muscle percentage, and total muscle mass compared to girls. 3. The body mass index, waist circumference, body fat percentage, and degree of obesity showed a weak positive correlation with the Badgan-dan and Badgan-khii constitutional types. In contrast, skeletal muscle mass, muscle weight, body water percentage, and body protein percentage demonstrated a weak positive correlation with the Khii-shar and Shar-khii constitutional types.

BACKGROUND. As long ago times or perhaps longer, people were using insects as medicines for healing wounds, preventing infections and improving health. Some of these are purely anecdotal, while others have proven basis in fact as tested by modern medicine.Usage of insects intraditional medicine was recorded since time immemorial.Insects and their substances have been used as medicinal resources by different cultures since ancient time because of chemical compounds - e.g. pheromones, defensive sprays, venoms and toxins, which were sequestered fromplants or prey and later concentrated or transformed for their own use.In many parts of the world,different sections of the society have been using medico-entomological drugs to this day in their lives.A numberof studies has in recent years drawn attention to thetherapeutic value of certain species of insects, their products, and their developmental stages.As has been documented insects can be a source of drugs used in modern medicine, since compounds of insect origin can have immunological, analgesic, antibacterial, diuretic, anaesthetic and anti-rheumatic, antitumor properties. Numerous insect originated materia medicain Mongolian traditional medicine contribute this source of therapeutics and variety of ancientmedical treatises by local authors as well as translations of renowned Ayurvedic medical books about animals as medicine exist.Knowledge about therapy with insects in Mongolian traditional medicine is less studied even they have been used broadly since ancient time. Several orthodox practitioners have surveyed the therapeutic potentials of defensive agents in dark beetleknown as “stink beetle” in the past.Yet the scientific community has to give thismajor and crucial component of traditional Mongolian medicine the attention it deserves, scientific knowledge about biologically active principles within medicinal insect remain poorly unknown. AIM OF STUDY.To define chemical analysis of ethanol whole body extract of Tenebrionid beetles. METHOD AND RESULT. We collected Tenebrionid beetles from local regions including desert, grassland, and to make an 40% ethanol extract of whole body to determine species of Tenebrionid beetles by entomoscope. After 30 days for saving in organic extract, to determine chemical composition of filtered 2 ml sample solution by high performance liquid chromatography - mass spectrometry (HPLC-MS). Using digital usb microscope 2.0 mp to confirm special characters of Tenebrionid beetles to Tenebrionid B.miliaria in biological termin. In HPLC-MS, octadecanoic acid is presented in 2 regional samples. CONCLUSION. Octadecanoic acid, the surface lipid of the insect was determined from the ethanol whole body extract of Tenebrionid beetles.