Objective: The study objective is to propose BIVA ellipses for the population and investigate its use to assess nutritional status through the BMI/age ratio and the cardiovascular risk through waist circumference (WC). Design: Age, weight, height and WC were recorded, along with the values of resistance (R), reactance (Xc) and phase angle (PA) by impedance. Student’s t-test and ANOVA were applied to ascertain the significance between means and a specific program was applied to investigate the significance between ellipses. Setting: Fortaleza, Brazil. Participants: A total of 467 students from public schools participated in the study: 120 children and 347 adolescents were evaluated, with respective means of age, weight and height of 8.2 years, 27.6 Kg and 1.29 m and 12.7 years, 48.6 Kg and 1.53 m. Results: The mean values of R/H, Xc/H and PA were 569.0 and 424.7 Ohm/m, 59.1 and 50.4 Ohm/m and, 5.9º and 6.8º for children and adolescents, respectively. The mean vectors for R/H and Xc/H show’s significant differences between for both age ranges and are inversely proportional to the BMI/A. As for WC, individuals without cardiovascular risk had higher R/H and lower Xc/H, but Xc and R in participants without cardiovascular risk were greater than with cardiovascular risk. Conclusions: It was possible to propose confidence and tolerance BIVA ellipses for children and adolescent’s clinical evaluation. The method was also suitable to identify cardiovascular risk ellipses in these age groups, but it was not possible to draw nutritional classifications ellipses by BMI/age data.

The enteric nervous system (ENS) is a neuron network present in the digestive system. Intestinal tract anatomic differences and cellular composition in different animals can help with interaction with environmental comprehension, which is a pertinent theme in molecular and cellular neurophysiology. In mammals, ENS is not the same in all species; rodents, generally, are great models for digestive tract adaptation study in physiologic process and environmental adaptation interpretation. This study is a narrative overview that describes morphological and cellular composition characterization in rodent neural enteric systems. Interstitial Cajal cells structural characteristics; ENS embryonic cell; system adaptation mediated by fasting, acute and chronic starve; gestation and lactation; temperature and diet; parasitism and rodent caloric restriction were aborded. Seasonal or transitory changes in intestine size probably occur when connected to food quality than its availability. Changes in female intestine size are reversible and periodic, increasing during lactation rodent as an attractive model for digestive flexibility study in the intestine size adjustment area. Enteric nervous system neuron morphological classification is presented, according to digestive tract localization and animal species. In conclusion, a significant change in intestinal mass and length in different rodent species can implicate intestinal motility during and after intestinal tract injury.