RESUMO
BACKGROUND: Reducing salt intake is known to be an important factor for lowering blood pressure and preventing cardiovascular disease. Estimating amount of salt intake is a necessary step towards salt intake reduction. Self-reported saltiness of diet is a method most easily used to measure a patient's salt intake. The purpose of this study was to examine the value of self-reported saltiness of diet in measuring salt intake. METHODS: We used data from 681 participants who visited a health center at a university hospital between August 2003 and November 2005. A self-administered questionnaire was used to collect information on self-reported saltiness of diet, other dietary habits and lifestyle factors. Salt intake was estimated on the basis of 24-hour dietary recall with a computer-aided nutritional analysis program (CAN-Pro 2.0, Korean Nutrition Society). RESULTS: There was no statistically significant difference between the mean salt intake of the self-reported salty diet group (13.7 ± 4.8 g/d) and the self-reported unsalty diet group (13.3 ± 4.4 g/d). If we assume calculated salt intake as the gold standard, the sensitivity and specificity of self-reported saltiness were 39.5% and 63.6%, respectively. Salt intake was increased with higher calorie intake, frequency of eating breakfast (≥5 times/wk) and being satiated with usual diet in men, but it was increased only with higher calorie intake in women. Regardless of actual salt intake, the group satiated with a usual diet tended to be in the group of self-reported salty diet. CONCLUSION: Self-reported saltiness of diet was not associated with actual salt intake. Further studies will be needed on the simpler and more objective tools to estimate salt intake.
RESUMO
We examined the associations between physical activity (PA), fitness and all-cause mortality and compared their contributions, taking smoking status into consideration. A retrospective cohort study of 18,775 men was carried out between May 1995 and December 2003. Fitness was measured by maximum oxygen uptake and regular PA was defined as at least three times a week, for more than 30 min of leisure time PA. During the mean 6.4 yr of follow-up, 547 deaths were recorded. The hazard ratio (HR) (95% confidence interval [CI]) of regular PA for all-cause mortality was 0.63 (0.52-0.76). The HRs (95% CIs) for men with middle and highest tertile levels of fitness were decreased by 0.58 (0.47-0.70) and 0.58 (0.45-0.75) in comparison to men with lowest one. The inverse association between fitness and mortality was significant among the men who did not engage in regular PA, but not among those who did (p for interaction=0.031). Smoking status did not influence on the associations between regular PA, fitness and mortality. Our result suggested that regular PA and fitness predicted mortality in men. The influence of fitness on mortality was pronounced in the men who did not engage in regular PA.
