Growth and body mass index of Brazilians ages 9 through 17 years.

Obesity during adolescence is considered a strong predictor of adult obesity, and obesity and overweight have been increasing among Brazilian adults. To gauge the relative frequency of overweight among adolescents in Brazil, we compared the distributions of body mass index (kg/m2) and stature in national population based samples of the U.S. and Brazil. U.S. adolescents were on average about 10 cm taller than Brazilians, although growth spurts occurred at the same age for both populations. Brazilian adolescents were leaner than their U.S. counterparts. This difference was reduced among girls in the postpubertal period. At age 17 years, U.S. boys were about 10 kg heavier than Brazilian boys, but the difference among girls was only 2 kg. In families above the poverty level in the more developed South region, body mass index distribution for boys was closer to that of the U.S., and older girls tended to have higher body mass index than U.S. girls. Within Brazil, body mass index varied by ethnicity with Mulattos, but not Blacks, of both sexes having lower body mass index than Whites of the same age. Urban adolescents had higher body mass index than those living in rural areas. In general, the patterns seen among Brazilian adults were found among children. Among girls, in particular, overweight has become an identifiable problem during adolescence.

High temporal, geographic, and income variation in body mass index among adults in Brazil.

OBJECTIVES: Population-based data on body mass index for developing countries are scarce. Body mass index data from two Brazilian surveys were examined to determine regional and temporal variations in the prevalences of underweight, overweight, and obesity. METHODS: Nationwide surveys in 1974/75 and 1989 collected anthropometric data in Brazil from 55,000 and 14,455 households, respectively. Trained interviewers used the same methods to measure weight and stature in both surveys, and survey designs were identical. Prevalences of underweight, overweight, and obesity were determined for persons 18 years of age and older. RESULTS: In the 1989 survey, body mass index varied greatly according to region of the country, urbanization, and income. In the wealthier South, the prevalence of overweight/obesity was the highest and the prevalence of underweight was the lowest; in the poorer rural Northeast, these patterns were reversed. For both surveys, overweight/obesity was more common among women than among men and peaked at age 45 to 64 years in both sexes. Over the 15 years between surveys, the prevalence of both overweight and obesity increased strikingly. CONCLUSIONS: In contrast to findings in developed countries, obesity in Brazil was positively associated with income and was much more prevalent among women than among men. For Brazilian women, the overall prevalence of overweight was nearly as high as that among women in the United States.

Chronobiology courses at the University of São Paulo/Brazil: a four-year experience.

We describe the didactic experience of graduate and post-graduate courses on chronobiology in São Paulo, Brazil.

Lack of similarity between the effect of lesions of the suprachcasmatic nucleus and subparaventricular hypothalamic zone on behavioral circadian rhythms

Rats were submitted to eletrolytic lesion of either the suprachiasmatic nucleus (SCN) or the subparaventricular hypothalamic zone (SPVH) and the effects on circadian behavioral rhythms were compared. While the SCN lesion abolished the circadian rythmicity of all behavioral patterns, the SPVH lesion only abolished that of the eating and drinking behavior and reduced the amplitude of a behavioral item usually associated with REM sleep

Lack of similarity between the effect of lesions of the suprachiasmatic nucleus and subparaventricular hypothalamic zone on behavioral circadian rhythms.

Rats were submitted to electrolytic lesion of either the suprachiasmatic nucleus (SCN) or the subparaventricular hypothalamic zone (SPVH) and the effects on circadian behavioral rhythms were compared. While the SCN lesion abolished the circadian rhythmicity of all behavioral patterns, the SPVH lesion only abolished that of the eating and drinking behavior and reduced the amplitude of a behavioral item usually associated with REM sleep.

Perinatal malnutrition, suprachiasmatic nuclear lesioning, and circadian-ultradian aspects of spontaneous behavior of albino rats.

The effect of reducing the dietary protein content at different stages of development was investigated. A group of control rats was fed a diet with 25% protein throughout the entire study. Four other groups were fed only 6% protein in a diet isocaloric with the control diet. In an "intrauterine"-deprivation (prenatal) group, the feeding of the low protein diet was limited to the span from mating to delivery. In a "postnatal"-deprivation (lactation) group, the reduced protein diet was limited to the 25 days allowed for lactation. In a "perinatal"-deprivation group, the low-protein diet was fed during both the pregnancy and the 25 days after birth. Protein deprivation in a "preperinatal" group started 1 month before mating and continued throughout gestation and lactation to day 25 after birth. Except for the perinatal group, consisting of two animals, other groups consisted each of three or four rats. Behavioral variables--activity, rest, eating, drinking, exploring, grooming, curling up, and lying down--were studied in rats from each group at 90 days of age for 3 days at consecutive near-12-min intervals for observation spans of 1 min. Two animals subjected to bilateral suprachiasmatic lesions, subsequently validated histologically, and two sham-operated controls were also investigated. Both the population-mean and the single cosinor methods were used for data analysis in conjunction with linear least-squares spectra. Cosinor methods allow the rejection of the zero-amplitude assumption on a group basis for the intact controls (P = 0.007), the intrauterine malnutrition group (P = 0.034), the lactation group (P = 0.059), the preperinatal group (P = 0.055), and on an individualized basis for the two animals constituting the perinatal group (P = 0.007 and 0.002). These results by population-mean cosinor are complemented by the single cosinor demonstration of rhythms for most animals and variables investigated. The results demonstrate, on an individualized basis, the persistence of circadian rhythms under differently timed conditions of protein malnutrition. The data on the behavior of rats with bilateral lesions of the suprachiasmatic nuclei show a circadian to ultradian variance transposition. In most behaviors, there are prominent ultradian rhythms, which, however, require study over longer spans with dense observations on additional animals.