[High-carbohydrate diets: effects on lipid metabolism, body adiposity and its association with physical activity and cardiovascular disease risk]. / Dietas hiperglicídicas: efeitos da substituição isoenergética de gordura por carboidratos sobre o metabolismo de lipídios, adiposidade corporal e sua associação com atividade física e com o risco de doença cardiovascular.

For many years the reduction in the dietary fat has been recommended to the population, in order to prevent cardiovascular diseases, obesity, type 2 diabetes mellitus, among other chronic diseases. The consequence has been the replacement of carbohydrates by fat, resulting in the adoption of high carbohydrate diets. However, it has been still discussed if very rich carbohydrate diets should be recommended to the general population. Researches point out controversies about the association between these dietary habits and harmful effects on health and metabolic aspects, such as raise in de novo lipogenesis and triglyceride concentration, reduction in HDL concentration and effects on adiposity. This review evaluates the effects of diet modification, particularly the high-carbohydrate diet, in cardiovascular risk factors such as dyslipidemia and obesity. It also reviews its interaction with physical activity since it is still unknown with which extension it can minimize possible harmful effects of high carbohydrate diets in the long term.

Dietas hiperglicídicas: efeitos da substituição isoenergética de gordura por carboidratos sobre o metabolismo de lipídios, adiposidade corporal e sua associação com atividade física e com o risco de doença cardiovascular / High-carbohydrate diets: effects on lipid metabolism, body adiposity and its association with physical activity and cardiovascular disease risk

Há vários anos, vem sendo recomendada à população em geral a diminuição da gordura dietética, a fim de se prevenir doenças cardiovasculares, obesidade, diabetes mellitus tipo 2, dentre outras doenças crônicas. A conseqüência desta recomendação tem sido a substituição de gorduras por carboidratos, resultando na adoção de dietas hiperglicídicas. Porém, ainda é muito discutido se dietas hiperglicídicas devem ser recomendadas à população geral. Pesquisas apontam controvérsias a respeito da associação entre este tipo de dieta e efeitos deletérios sobre a saúde e aspectos metabólicos, tais como aumento da lipogênese de novo, aumento da trigliceridemia, diminuição das concentrações de HDL e efeitos sobre a adiposidade. Esta revisão aborda os efeitos de mudanças na composição dietética, particularmente da dieta hiperglicídica, sobre fatores de risco para doenças cardiovasculares, tais como dislipidemia, e obesidade. Revisa, também, sua interação com a atividade física, uma vez que ainda não se sabe com que extensão ela pode minimizar possíveis efeitos deletérios de dietas hiperglicídicas em longo prazo.

For many years the reduction in the dietary fat has been recommended to the population, in order to prevent cardiovascular diseases, obesity, type 2 diabetes mellitus, among other chronic diseases. The consequence has been the replacement of carbohydrates by fat, resulting in the adoption of high carbohydrate diets. However, it has been still discussed if very rich carbohydrate diets should be recommended to the general population. Researches point out controversies about the association between these dietary habits and harmful effects on health and metabolic aspects, such as raise in de novo lipogenesis and triglyceride concentration, reduction in HDL concentration and effects on adiposity. This review evaluates the effects of diet modification, particularly the high-carbohydrate diet, in cardiovascular risk factors such as dyslipidemia and obesity. It also reviews its interaction with physical activity since it is still unknown with which extension it can minimize possible harmful effects of high carbohydrate diets in the long term.

Selective underreporting of energy intake in women: magnitude, determinants, and effect of training.

OBJECTIVE: The aim of this study was to quantify underreporting of energy intake in Brazilian women; identify underreporting determinants; find out if underreporting was selective and; test if a motivational multimethod training, in combination with providing the subjects some results from the prior recording period, was able to reduce underreporting. DESIGN: Energy intake (EI) was assessed by a 7-day diet record. Energy expenditure (EE) was calculated by heart rate monitoring. EI:EE ratio lower than one in subjects who did not lose weight in one month was considered underreporting. Underreporting was correlated with anthropometric, behavioral, and psychological parameters. Food and nutrient consumption was compared between underreporters and non-underreporters. A focus group investigated the main causes of underreporting. Subjects were told that the earlier food records' results were unrealistic and submitted to a motivational training. Then, they were reevaluated for underreporting. SUBJECTS: Subjects were recruited by advertisements for a physical activity program. Thirty-eight healthy women, 13 normal-weight (34%), 13 overweight (34%), and 12 obese (32%), enrolled in the study. Three subjects (2 normal-weight and 1 obese) (8%) withdrew. STATISTICAL ANALYSIS PERFORMED: Analysis of variance, paired t tests, and simple linear regression. RESULTS: Seventeen women (49%) underreported their EI by 21%. A significant negative correlation was found between social desirability and EI:EE. Undereating, errors in portion sizes estimation and the inconvenience of having to record everything that was eaten seemed to explain underreporting. Mean portion sizes did not differ for underreporters and non-underreporters. Fewer self-reported years of education was correlated with underreporting only among normal-weight women. Training and confrontation with earlier results reduced underreporting rate to 33%, but did not affect macronutrient densities. Applications/conclusions Subjects tended to report their intake in a socially desirable way, by eating or reporting less frequently foods considered unhealthful or fattening, like sweets and fried foods. Inclusion of social desirability score as a covariate in studies that rely on self-reports of food intake may be useful. A motivational training program, developed in such a way that subjects are comfortable reporting intake of foods considered socially undesirable, in combination with confrontation with earlier results of dietary assessment and use of portion size measurement aids, can be used to attenuate underreporting.