Hugo Kesteloot

Bread as a source of salt: an international comparison.

OBJECTIVE The salt (NaCl) content of bread, obtained from Belgium and 25 other regions or countries worldwide, was analyzed to evaluate the importance of bread as a source of dietary salt in a population. METHODS A total of 1166 dried bread samples were analyzed using a hot HCl extraction technique followed by flame photometry and performed by the same laboratory technician in Leuven (Belgium); 534 samples from Leuven were analyzed over 10 time periods from 1967-73 to 1992 together with 562 samples from 11 other European countries, 44 from the United States and Peru, and 26 from Asia. RESULTS The average mean salt content of fresh bread (= dried bread times 0.6) in European countries was 12.4 +/- 1.7 g/kg for white and 13 +/- 1.0 g/kg for brown bread. In Japan and Korea it was about 8.5 g/kg and in Pakistan, Thailand, Nepal, and Laos about 5 g/kg. The mean sodium/potassium ratio with Na and K in mmol was 8.0 for white and 4.5 for brown bread, much higher than the recommended value of 1.0. Bread with a very low salt content was found in certain areas of Peru, Spain, and Italy. CONCLUSION The overall salt content of bread in Western countries is excessive, and a gradual reduction is highly desirable.

Differences in all-cause, cardiovascular and cancer mortality between Hong Kong and Singapore: Role of nutrition

Background: The majority of inhabitants in Hong Kong and Singapore are ethnic Chinese, but all-cause and cardiovascular mortality rates in these two regions are markedly different. This study describes differences in the magnitude and trends in mortality and attempts to explain these differences. Methods: Data of mortality rates in 1963–1965 and 1993–1995 in the age class of 45–74 years, dietary habits and other factors were compared between Hong Kong and Singapore using Japan, Spain and the USA as reference countries. Mortality and food consumption data were obtained from WHO and FAO, respectively. Results: Large differences in all-cause and cardiovascular mortality exist between Hong Kong and Singapore. The difference in total cancer mortality was less consistent and smaller. The most pronounced finding was that ischemic heart disease mortality in 1993–1995 was 2.98 and 3.14 times higher in Singapore than in Hong Kong in men and women, respectively. Of the five countries considered, Singapore has the highest all-cause mortality in both sexes in the period of 1960–1995. The ratio of animal to vegetal fat was higher in Singapore (2.24) than in Hong Kong (1.08). Singapore had higher serum concentrations of total cholesterol and low-density lipoprotein cholesterol than Hong Kong, but the opposite result was observed for high-density lipoprotein cholesterol. Conclusions: There are striking differences in all-cause and cardiovascular mortality between Hong Kong and Singapore. These differences can be most reasonably and plausibly explained by their differences in dietary habits, for example, a higher consumption of coconut and palm oil, mainly containing saturated fat, in Singapore.

Cancer mortality and age: Relationship with dietary fat

Highly significant correlations exist between total cancer mortality and age expressed by a log total cancer mortality-log age equation (mean r2 0.991 in men and 0.996 in women) or by a second-order polynomial equation including age and age2 (mean r2 0.999 in men and 0.998 in women). In all countries considered (n = 32), the second-order term of age is negative, indicating a decrease in the rate of rise of log cancer mortality at older age. This could be explained by a lesser accuracy of the diagnosis of cancer at older age, by selective survival of subjects resistant to cancer, by a cohort effect, or by a decrease in the rate of growth of cancer at older age. The decrease in the rate of rise of cancer mortality after 65 years of age occurs in all countries and applies to nearly all cancers except breast cancer in women after 75 years of age. A high cancer mortality in a country is characterized by a low intercept and a steep slope of the log mortality-log age equation. These parameters are influenced by dietary fat intake in men and women, with saturated fat increasing total cancer mortality and the ratio of polyunsaturated to saturated fat and the ratio of unsaturated to saturated fat decreasing it. The data on dietary fat were obtained from the Food and Agriculture Organization of the United Nations (FAO) food balance sheets (n = 32) and from dietary surveys (n = 21). Both vary in the same direction, but only the dietary data from the FAO correlate significantly with cancer mortality. This finding points toward a relationship between the level of dietary fat intake and total cancer mortality at the population level.

On the relationship between all-cause, cardiovascular, cancer and residual mortality rates with age

Background The existence of a highly significant linear relationship between the natural logarithm (ln) all-cause mortality rate and age at the population level is firmly established (r 2<0.99). The slope and intercept of the equation, however, vary markedly between populations. Whether this relationship also applies to specific disease entities has not been established. Methods Use was made of mortality rates for all-cause, total cardiovascular, total cancer and residual diseases. The midpoint of 5-year age classes between the ages of 35 and 84 years, obtained for both sexes, were analysed. The mean of the three latest available years, from the period 1997–1999 were used. Results The relationship also applies to a slightly lesser degree to the relationship between total cardiovascular mortality rate, consisting predominantly of ischemic heart disease and stroke, and age (r 2<0.99). Marginally better relationships are obtained using a second-degree polynomial equation between ln all-cause mortality rate and age, age2 as independent variables. Total ln cancer mortality rate, however, behaves differently with a significant negative deviation of the mortality rate from linearity at older ages. Residual mortality (non-cancer, non-cardiovascular) mortality shows a mirror pattern to cancer mortality. This residual mortality expressed as a percentage of all-cause mortality varies markedly between populations. The level of some major constituents of the residual mortality rates (respiratory diseases, pneumonia, ill-defined causes and senility) also varies markedly. Conclusions The magnitude of the variation suggests misclassification or misdiagnosis of several important disease entities, for example, between senility and stroke or between pneumonia and lung cancer. This questions the validity of disease-specific mortality rates especially at older ages, making their comparison between countries less reliable. Eur J Cardiovasc Prev Rehabil 12: 175–181

Alcohol drinkers overreport their energy intake in the BIRNH study: Evaluation by 24-hour urinary excretion of cations

Objective: Alcohol drinkers are generally considered to underreport their alcohol intake, but little is known about whether they correctly report their energy intake (EI). We assessed the validity of the reported energy intake of alcohol drinkers using the 24-hour urinary (U) excretion of potassium (K) and sodium (Na) as biomarkers. Methods: A total of 2,124 men and 1,998 women 25 to 74 years of age with a 24-hour urine collection, a random sample of the Belgian Interuniversity Research on Nutrition and Health (BIRNH), were studied. Dietary intake (D), including alcohol consumption, was assessed by a one-day food record. Basal metabolic rate (BMR) was predicted from age, gender and weight. As a measure for the degree of reporting error, D-K/U-K, D-Na/U-Na, EI/U-K, Non-alcohol EI/U-Na (NAEI/U-Na), EI/U-Na, EI/U-creatinine and EI/BMR ratios were calculated and compared among non-, moderate and heavy drinkers in both genders. Results: EI, NAEI and all seven ratios examined generally increased with the level of alcohol intake in both genders. After adjustment for age, body mass index, smoking and educational level, most ratios were significantly higher in moderate drinkers (p < 0.02 to p < 0.0001) and in heavy drinkers (all p < 0.0001) than in non-drinkers. These differences were most significant in male heavy drinkers. The exceptions were D-K/U-K, D-Na/U-Na and NAEI/U-Na in moderate and female heavy drinkers and EI/U-K in male moderate drinkers. The estimated amount of the overreporting of EI by heavy drinkers was 27.8% in men and 13.7% in women. Conclusions: This study provides evidence that EI and NAEI obtained from the BIRNH study was overreported among alcohol drinkers, especially among male heavy drinkers. It also indicates that EI from alcohol replaced EI from food.