Clinical trials in nutrition

Trials of nutritional intervention in a wide range of health and disease states, preventive and therapeutic, are required. Not only has the emergence of chronic non-communicable disease (CNCD) with acknowledged nutritional pathogenesis created this imperative need, but so also have other conditions which, previously, had not been regarded as nutritionally based. Among the latter are health problems associated with ageing: the menopause, a decline in immune function, and a decline in cognitive function. At the same time, there is a new set of materno-foetal and infant nutrition issues for investigation which relate to new food exposures and the long-term effects of nutritionally mediated gene expression. The emergence of the new food science of phytochemicals with human biological importance also sets the scene for their evaluation in traditional diets and novel foods. Such trials are more complex than comparable pharmacotherapeutic studies because of the complexity of food chemistry, as well as the food behavioural changes which may accompany a nutritional intervention, and the general problem of there not being a 'gold standard' for food intake methodology. Choice of study population is also a key issue in relation to the extrapolation of findings from a particular trial, with population representativeness being an advantage. In order to obtain useful information on manageable sample sizes, either intermediate end-points (short of morbidity and mortality) need to be studied or high-risk groups (such as the aged) need to be recruited. There are some unique ethical issues which must inform clinical nutrition trials. These include certain preventive imperatives like the right to be fed, the risks in disruption of food cultures and the need for food security and sustainability. Rapid changes in the food supply do, however, make such trials more important, while the value of food-health knowledge that cannot be obtained by trial must still be appreciated.

The influence of fish, meat and polyunsaturated fat intakes on platelet phospholipid polyunsaturated fatty acids in male Melbourne Chinese and Caucasian

OBJECTIVE

The aims of this study were to investigate (1) platelet phospholipid (PL) polyunsaturated fatty acid (PUFA) composition in subjects who were the Melbourne Chinese migrants, compared with those who were the Melbourne Caucasians and (2) the relationship between platelet PL PUFA and intake of fish, meat and PUFA.

DESIGN

Cross-sectional comparison of the Melbourne Chinese and Caucasians.

SETTING

Free-living male subjects.

SUBJECTS

Ninety-seven Melbourne Chinese migrants and 78 Melbourne Caucasians who were recruited in Melbourne.

OUTCOME MEASURES

Dietary intake was assessed using a semi-quantitative food frequency questionnaire. The platelet PUFA was measured by gas-liquid chromatography.

RESULTS

The Melbourne Chinese had significantly higher proportions of platelet PL 20:5n-3 (P=0.006), 22:6n-3 (P<0.0001), total n-3 (P=0.027) and 22:5n-6 (P=0.0002), and a significantly higher intake of fish (P=0.012) and white meat (P=0.0045) compared with the Melbourne Caucasians. In addition, the Melbourne Chinese had significantly lower proportions of 20:3n-6 (P=0.023), 20:4n-6 (P<0.002), 22:4n-6 (P<0.0001), total n-6 (P=0.037), 22:5n-3 (P<0.0001) and ratio of n-6/n-3 (P=0.011), and a significantly lower intake of red and total meat (P<0.0001) than the Melbourne Caucasians. Fish consumption was significantly positively correlated with platelet PL 20:5n-3 and 22:6n-3, and significantly negatively correlated with 22:5n-3 (P<0.05). Meat consumption was significantly positively correlated with 22:5n-3 and significantly negatively correlated with 22:5n-6, 20:5n-3 and 22:6n-3 (P<0.05). Dietary PUFA intake was significantly positively correlated with 20:3n-6, 22:4n-6 and 22:5n-3, and significantly negatively correlated with 22:5n-6, 20:5n-3 and 22:6n-3 (P<0.05).

CONCLUSIONS

Compared with Caucasians, the Melbourne Chinese had a significantly higher level of platelet PL n-3 PUFA, which might contribute to the low CVD mortality in this population. Platelet PL 20:5n-3 and 22:6n-3 were significantly positively correlated with fish intake, and negatively significantly correlated with dietary intake of meat and PUFA, while 22:5n-3 was significantly positively correlated with dietary meat and PUFA intake, and significantly negatively correlated with fish intake. Dietary intake of PUFA and fish are potential confounding factors for assessing the effects of meat consumption on platelet PL individual PUFA. Dietary intake of PUFA and meat did not influence the incorporation of fish long chain n-3 PUFA to platelet PL in this study population.

SPONSORSHIP

Palm Oil Research Institute of Malaysia, Meat Research Corporation Australia.

The use of knee height to estimate maximum stature in elderly Chinese

Loss of height occurs in the elderly. Not only is this height valuable to assess, but it creates difficulty for comparisons using equations based on estimates of stature in adult populations which often overlook the loss of height with age. Alternatives, such as the use of arm-span or hip length as surrogates for maximum stature (MS) during adulthood, have been proposed. In a study of 247 (130 men and 117 women) adult ethnic Chinese living in Melbourne, Australia, we tested the hypothesis that knee height is independent of age and attempted to devise an equation for the estimation of maximum stature (MS) in the this elderly group (aged 65 yrs) of this population. Anthropometric indices, including body weight, stature, arm-span, and knee height were twice measured using standard methods described by Lohman et al., and averaged for use in the analysis. In both men and women, the younger adults were taller and had a greater arm-span than their elderly counterparts: however, there was no difference in knee height or body weight between the two groups. Knee height was not associated with age, while stature and arm-span correlated negatively with age. These findings suggest that knee height provides for a valid estimate of MS during early adulthood than arm-span. Knee height is independent of age and does not appear to decreased over time, in spite of an expected cohort effect in this population. Arm-span, however, appears to change with a cohort as well as with age. Thus, there is a place in a life-time nutritional assessment of the aged to measure both arm-span as an index of cohort status and knee height for an individual's maximum achieved stature.

Health promotion projects: skill and attitude learning for medical students

OBJECTIVES

The aim of this health promotion project is to introduce students to appropriate skills and attitudes--as well as knowledge about health promotion strategies and methods. As part of this process, standardized procedures have been established to ensure that the projects are scientifically and ethically appropriate and adequately supervised. This project-centred course introduces the discipline of health promotion to third-year medical students at Monash University. It is aimed at introducing students to the range of health promotion concepts, providing them with experience of health promotion activities and involving them in consideration of the scientific, political and ethical issues arising from doctors' participation in health promotion.

DESIGN

As the major learning and assessment component of the unit, students participate in self-selected project groups of three to five students. Each group develops a topic for a health promotion activity in the community, carries out that project and presents the results as a poster as well as a written report.

SETTING

Monash University.

SUBJECTS

Third-year medical students.

RESULTS

Sixty per cent of each student's mark for the unit is based on the project. The posters produced by the project groups are placed on public display in a major teaching hospital for a week at the end of the unit. Public display of the posters helps each student to appreciate the variety of possible health promotion activities, and to appreciate health promotion as a scientific discipline. It also makes the project findings available to the public.

CONCLUSIONS

Student evaluation of the project, and community response to the projects--especially the poster display-- indicate that the project is both a highly effective learning experience and a health-promoting activity in its own right.

The role of income and education in food consumption and nutrient intake in a Chinese population

The purpose of this study was to investigate the role of socio-economic status in the transition of food consumption and nutritional status in a Tianjin population and to identify some related underlying nutritional problems in this population. A random representative sample of appproximately nine million people in Tianjin was obtained using the stratified multistage cluster sampling method. A total of 2236 eligible subjects (1096 men and 1140 women) aged between 15 and 64 years were enrolled in the autumn of 1992. Food weighing plus a three-day food record method were used to assess food consumption and nutrient intakes. The population was categorized into four income groups by average per capita income and three educational groups by years of education. There were marked differences in daily mean consumption of foods among groups with different income levels and educational attainment after adjustment for confounding factors. The low income and/or least education group consumed more cereals while the high income and/or most educated group consumed more fruit, milk and meat. Due to the differences in food consumption, intakes of protein, fat, riboflavin, calcium, selenium, zinc and vitamin E increased while intakes of carbohydrate and manganese decreased with increasing levels of income and education. Vitamin A, calcium and riboflavin intakes were low in all groups classified by either income or education. Vitamin A intake was lower in the low income group than in the other three groups but intakes of calcium and riboflavin were higher in the high income and/or the most educated group than in the other groups. Socio-economic status plays an important role in food consumption and nutritional status in this population. Low intakes of vitamin A, calcium and riboflavin exist in all socio-economic groups. However, higher income and/or educational attainment contribute to increased intakes of calcium and riboflavin. Higher income also relates to an increased intake of vitamin A.

Agreement of skinfold measurement and bioelectrical impedance analysis (BIA) methods with dual energy X-ray absorptiometry (DEXA) in estimating total body fat in Anglo-Celtic Australians

OBJECTIVE

To compare percentage total body fat (%BF) estimated by the four skinfold thickness measurement (SKF) and single-frequency bioelectrical impedance analysis (BIA) methods using three different sets of equations, to that assessed by the dual energy X-ray absorptiometric (DEXA) method using a Lunar DPX densitometer.

DESIGN

Cross-sectional study.

SUBJECTS

An Anglo-Celtic Australian population of 66 males and 130 females (age: 26-86 y).

MEASUREMENTS

%BF by anthropometry, BIA using three different sets of equations and DEXA.

RESULTS

Mean %BF assessed by DEXA (%BF(DEXA)) was similar to that estimated by SKF (%BF(SKF)) in males, while %BF(DEXA) was slightly higher in females. %BF estimated by BIA (%BF(BIA)) was significantly lower than %BF(DEXA) in females, regardless of equations used for calculation, while the level of agreement between BIA and DEXA in estimating %BF in males was dependent on prediction equations used for calculation of %BF(BIA). A better agreement was obtained from the use on the prediction equations of Segal et al (1988), compared to other two sets of equations. The agreement between SKF or BIA and DEXA declined with increasing %BF.

CONCLUSIONS

There was a good agreement between DEXA and SKF, and slightly less so between DEXA and BIA, in estimating %BF in an Anglo-Celtic adult population. The agreement in most cases, however, was dependent on the degree of body fatness. In comparison to DEXA, both SKF and BIA, with the use of the equations of Segal et al (1988), are applicable to estimate %BF in an Anglo-Celtic Australian population.

Cross-cultural comparison of Lp(a) profiles

Lipoprotein(a) (Lp(a)) and apolipoprotein(a) (apo(a)) phenotypes as genetic markers for coronary heart disease (CHD) have been the focus of great interest in recent times. Included in this study were four Australian populations comprising 348 Anglo-Celtic Melburnians (157 men and 191 women), 339 Chinese Melburnians (169 men and 170 women), 402 South Asian Melburnians (216 men and 186 women) and 394 Aboriginal Australians from Western Australia (175 men and 219 women). Plasma Lp(a) concentrations were more highly skewed towards the lower range in the Chinese and Aboriginal groups than in the Anglo-Celtics and South Asians. Approximately 33% of Anglo-Celtics, 20% Aboriginals, 13% Chinese and 44% South Asians had plasma Lp(a) levels above the generally accepted risk threshold values of 300 mg/L. In Aboriginals and Chinese, the S4 apo(a) phenotype predominated while in Anglo-Celtics and South Asians, the highest frequency occurred in the S3 phenotype. In the S4 phenotype, Lp(a) values varied between the four populations but there was no significant difference in concentration between gender.

Food intake patterns in urban Beijing Chinese

This study investigated the food consumption patterns of 430 Beijing Chinese adults and assessed the impact on these patterns of the following socio-demographic characteristics: gender, age, educational achievement, and gross household income. Food intake by category, food variety and meal patterns were assessed using a 156-item food frequency questionnaire. It was found that gender and age were the most important factors to influence food consumption patterns. Men consumed more wheat products, red meat and tea, whereas women consumed more vegetables, fruit, nuts, fish, eggs and milk. Women also tended to consume a wider variety of food than did men. Furthermore, it was found that younger and more educated people tended to consume a wider variety of food. Age also had an important influence on the food intake. Younger and generally more educated adults tended to consume foods associated with affluence: meats, soft drinks and beer, while the older population tended to consume more vegetables (women only), milk and tea in their diets. Because education is closely correlated with age in this Beijing Chinese population, it appeared to have little effect on the food intake patterns, after adjusting for age. The older members of this population, who probably have a decreased functional reserve of nutrients, and the less educated, appeared not to be taking advantage of the availability of a wide variety of food, further increasing the risk of nutrient deficiency. On the other hand, the younger and more educated, who tended to consume a wide variety of foods, were more likely to maintain adequate nutritional standards. However, their tendency to consume food associated with affluence, such as meat and beer, may point toward an increased risk of those diseases prevalent in affluent societies, such as obesity, diabeties, cardiovascular disease, certain cancers and osteoporosis. Ongoing nutrition surveillance and appropriate nutrition education will be required increasingly for Beijing Chinese and similar communities.

Body composition as a predictor of blood pressure in three communities in Guangdong province, China

The aim of this study was to compare mean blood pressure (BP), anthropometric and body compositional measurements in three Chinese communities and to examine relationships between BP and body composition in these communities. A total of 935 adult (aged >= 25 years) men and women were randomly sampled from three communities (Chauzhou County speaking Teochew, Meixian County speaking Hakka, and Xinhui speaking Cantonese) in Guangdong Province, China. Self-administered questionnaires about food habits, lifestyle and health status were completed. Body weight, stature, waist and hip circumferences and systolic and diastolic blood pressures were measured. Body mass index, waist to hip ratio, fat free mass, total body fat mass and the percentage body fat were calculated to assess body composition. No significant differences were found in stature, body mass index, umbilical circumference, hip circumference, fat free mass, percentage body fat and defined hypertension between the three communities. However, the waist to hip ratio was lower in Chauzhou men than Meixian women. The mean BPs were different between the communities and mean blood pressure was the highest in the Chauzhou community. Intra-community non-parametric relations between BP and body composition were found mostly in men with increased total and abdominal fatness positively related to BP. The relationships of the aggregate communities with blood pressure were found consistent with those for intra-community analyses, although the body fatness-blood pressure relationship was then evident without exception. Anthropometrically assessed body composition predicts BP in Chinese men, but to a lesser extent, in Chinese women in Guangdong Province, China.

Prevalence of coronary risk factors in a sample of Chinese women in Kuala Lumpur

Several risk factors for cardiovascular disease amongst a sample of urban Chinese women were investigated. These factors included body mass index (BMI), waist hip ratio, total blood cholesterol (TC), HDL-cholesterol and Lp(a) levels, blood pressure, cigarette smoking, family history of chronic disease, dietary habits and frequency of selected food intake. The subjects were found to have coronary risks with respect to BMI and TC level, both of which increased with age of the women. Hypertension, HDL-cholesterol and Lp(a) levels appeared not to pose as risk factors amongst these subjects. Dietary habits and intake showed significant correlations with subjects' BMI status. Health promotion is called for towards reducing the modifiable coronary risk factors.

Food intakes of adult Melbourne Chinese

Food intake patterns of 545 adult Melbourne Chinese were studied in 1988 and 1989 using a 220-item food-frequency questionnaire appropriate for Chinese eating practices. Men and women were compared, adjusting for age, time in Australia and education. Men consumed more rice and alcoholic beverages as energy. In women, the energy intake was derived from foods of traditional Chinese types. There were two types of consumption patterns: in the first group were those who acculturated towards an Australian way of eating by replacing some traditional Chinese foods, such as rice, pork, leafy green and cruciferous vegetables, soups and tea, with 'new foods', such as wheat products, red meats and coffee; in the second were those who limited their intake to a handful of traditional Chinese foods as the major source of energy. The educated, the professional and those with an administrative profession, the Australian-born and those with a longer length of stay fitted into the first group, and were more acculturated towards Australia than those born in the People's Republic of China or Vietnam and who migrated at an older age. The first group may benefit from the best of both worlds, but may risk the diseases of an industrialised society. The second group may be trapped at a cultural crossroads and may be unable to make appropriate food choices. Public health efforts in Australia, where one in every five is overseas-born, should provide for nutrition and health education for new and aged migrants of non-European cultural backgrounds.

Cigarette smoking and socio-economic indicators as determinants of body fatness in three Southern Chinese communities of China

Obesity is one of the major risk factors for cardiovascular disease and non-insulin dependent diabetes mellitus. This study describes cigarette smoking and the socio-demographic differences of body fatness in three sub-ethnic distinctive communities in Guangdong Province, China. In this study, 935 adult Chinese (Chauzhou - 203 men and 111 women; Meixian - 169 men and 140 women; Xinhui - 194 men and 118 women) were randomly sampled from three communities. A standard protocol was used to measure stature, body weight, waist and hip circumferences. Body mass index (BMI) and waist-to-hip circumference ratio (WHR) were calculated as measures of total body fatness and abdominal body fatness, respectively. The questionnaire was self-administered and demographic and lifestyle factors were assessed. WHR was positively related to age in men (p=0.0001) and in women (p=0.0001) while BMI was associated with age only in women (p=0.0001). In women, WHR was significantly related to education levels after adjusting for age and BMI (p=0.0300). In men, BMI differed by educational level, after adjusting for age and WHR (p=0.0329). BMI was significantly associated with occupational status in men, after adjusting for age and WHR (p=0.0004). Gross household income was significantly associated with WHR in men, after adjusting for age and BMI (p=0.0469). Male smokers had a significantly lower mean BMI than the non-smokers, after adjusting for age and WHR (p=0.0037). Marital status was not related to body fatness measurements after adjusting for age and WHR. The differences in body fatness in Chinese living in Southern China can not be totally explained by educational level, occupational status, marital status, gross household income and cigarette smoking, particularly in women. Age was the only consistent predictor of abdominal body fatness in both men and women and also of total body fatness in women.

Cardiovascular risk factor prevalence in three Chinese communities in 1989

The cardiovascular risk prevalence of 935 adult Chinese living in Chauzhou, Meizhou, and Xinhui cities of Guangdong Province, China, is reported. The three communities are geographically separated, and represent the three major dialect group in Guangdong Province (Teochew, Hakka and Cantonese respectively) which are also the major donor populations of overseas Chinese to Australia and South East Asia. Taking into account historical data, the conventional cardiovascular risk factor prevalence of these combined communities in China as a whole is on the increase and approaches or even exceeds that in Western Society. However, the three communities are not very alike in their prevalences of individual conventional cardiovascular risk factors, notably for hyperlipidaemia (most prevalent in Chauzhou), hypertension (most prevalent in Chauzhou men at 12.4% and least in Meizhou women 5.0%) and cigarette smoking (most prevalent in Xinhui men at 72.7% and least in Xinhui women, 0%). They are similar in stature, body weight, BMI, and waist-to-hip ratio, with very low prevalences of overweight/obesity, or abdominal obesity. An understanding of the contributors to sub-ethnic difference in cardiovascular risk should emerge with further study of these Chinese populations.

Helicobacter pylori in Melbourne Chinese immigrants: evidence for oral-oral transmission via chopsticks

The Helicobacter pylori seroprevalence in a representative population of 328 Melbourne Chinese immigrants (162 men and 166 women) aged 25 years and older were studied. The population consisted of Chinese people born in China/Hong Kong (n = 110, 33.5%), Vietnam (n = 79, 24.1%), Malaysia/Singapore (n = 102, 31.1%), and elsewhere (n = 37, 11.3%). The overall seroprevalence of H. pylori was 59.5%; 60.5% in men and 58.4% in women. Gender specific analysis showed associations between higher seroprevalence and several socio-demographic factors; in men, age (P < 0.0001), lower education level (P < 0.002), cigarette smoking (P < 0.042), the use of antibiotics (P < 0.015) and chopsticks (P < 0.047), and in women, lower socioeconomical status [education level (P < 0.030), gross household income (P < 0.0001) and occupational status (P < 0.0001)] and use of chopsticks (P < 0.002). Seroprevalence differed between immigrants of various birthplaces (P < 0.001); those born in Malaysia/Singapore (43.1%) were lower than those born in China/Hong Kong (68.2%), Vietnam (68.4%), and elsewhere (59.5%). Immigrants of various birthplaces also differed in their pattern of socio-demographics. Multivariate analyses showed that risk factors for H. pylori infection within the Melbourne Chinese immigrants were, in men, age (B = 1.081) and birthplace (B = 1.769) and, in women, household income (B = 0.541) and use of chopsticks (B = 1.654). This study suggests person-to-person transmission of H. pylori via the oral-oral route with ethno-specific food practices an important risk factor.

Anthropometric indices among adult Melbourne Chinese Australians

Anthropometric indices of adult Chinese living in Melbourne, Australia, were studied. 540 (271 men and 269 women) adult Melbourne Chinese were recruited for a study of food habits and cardiovascular risk factor prevalence; all had stature, body weight and waist and hip circumferences measured. Body mass index and waist-to-hip ratio were estimated, along with fat-free mass, total body fat and the percentage body fat, using established or published formulae. Stature was negatively associated with age and positively related to education level. The Australian-born Chinese had the greatest anthropometric indices; those born in China and Hong Kong had a similar anthropometric profile; the anthropometric profile of Vietnamese Chinese was similar to that of their Australian born counterparts and was significantly greater than that of their counterparts born in China and Hong Kong. Our study suggests that a favourable environment can promote full genetic potential in growth, as evident in the Australian-born Chinese. Those born in Vietnam appeared to have taken full advantage of the Australian environment and showed an elevation of body composition.

Changes in serum carotenoids in subjects with colorectal adenomas after 24 mo of beta-carotene supplementation. Australian Polyp Prevention Project Investigators

The effect of beta-carotene supplementation on major serum carotenoid fractions (lutein/zeaxanthin, beta-cryptoxanthin, lycopene, alpha-carotene, and beta-carotene) was investigated in 224 people with colorectal adenomas (139 men, 85 women) recruited for the Australian Polyp Prevention Project (APPP). Each subject was randomly assigned to take either 20 mg beta-carotene/d or placebo over 24 mo. Besides the expected increase in serum concentration of beta-carotene (1073% in men, 839% in women), lycopene (176% in men) and alpha-carotene (211% in men and 166% in women) concentrations were also increased after body mass index, baseline concentration, change in respective carotenoid intake, and other confounding factors were adjusted for. The increase in serum concentrations of these carotenoids after beta-carotene supplementation suggests that beta-carotene may interact biologically with other carotenoids and such interaction would need to be taken into consideration when the protective effect of beta-carotene supplementation for cancer or other diseases is examined.

Assessing food and health relationships: a case study of blood pressure determination in adult Melbourne Chinese

An effective public health approach to cardiovascular disease prevention should be one which gives the general public alternatives in choice when fat, salt and sugar are reduced in the diet. Fat, salt and sugar are nutrients which can be found in various foods. Public health educators convert these nutrients into foods so that the general public can engage in daily food choice. The usual nutrient-to-food conversion is indirect and can be misleading. For example, we are still unclear as to the potential benefit of polyunsaturated margarine over butter or olive oil. In a base-line data analysis of Chinese adults in Melbourne, we related food intake in addition to nutrients to major cardiovascular risk factors. In all models, food intake accounted for a higher variation of major cardiovascular risk factors than did nutrient intake. Melbourne Chinese, who consumed a wide variety of foods and ate more fish, vegetable, and fruits, had a better cardiovascular risk profile. The findings are of importance in public health significance. Longitudinal documentation of changing food intake, in addition to nutrients, and associated change in cardiovascular risk factors in this population are needed at this stage followed by further work to confirm its generalizability to Australians at large. This report focuses on findings of blood pressure determination in 547 adult Melbourne Chinese and reviews the way in which food and health relationships may be studied.

Cardiovascular risk in adult Melbourne Chinese

Chinese migrants have low cardiovascular mortality, particularly in their first 10 years of residence in Australia. The apparent increase in cardiovascular deaths among Asian migrants who have lived in Australia for more than 10 years suggests that cardiovascular risk transition may occur soon after migration. In this descriptive study, we found that Melbourne Chinese were not low in cardiovascular risk factors as usually defined. The prevalence of hyperlipidaemia (7.7 per cent for men and 5.2 per cent for women) was similar to the prevalence for other Australians (6.8 per cent for men and 4.4 per cent for women). In spite of low mean blood pressure (systolic blood pressure 114 +/- 23 mmHg (mean +/- standard deviation) and diastolic blood pressure 67.3 +/- 10.6 mmHg), Melbourne Chinese women were hypertensive as often as their Australian counterparts. The prevalence of cigarette smoking in men (26.9 per cent) was also comparable to prevalence for Australian males (24.1 per cent). Being slim is the only recognised cardiovascular protection that Melbourne Chinese may have. A high waist-to-hip ratio (0.91 +/- 0.054 for men and 0.88 +/- 0.077 for women), however, may outweigh the potential benefit of lower prevalence of overweight (17.7 per cent for men and 14.1 per cent for women). Melbourne Chinese men had a multiple risk-factor profile similar to their Australian counterparts. Differences in multiple risk factors in women were attributable to fewer Chinese women having a single risk factor (15.4 per cent versus 30.1 per cent).(ABSTRACT TRUNCATED AT 250 WORDS)

A food frequency questionnaire for use in Chinese populations and its validation

There is no gold standard in the assessment of individual dietary intake methodology. The choice of dietary method to estimate individual intake depends upon the study objectives for the assessment of individual intake. We adopted a food frequency questionnaire and modified it for use in a study of food habits and cardiovascular health status in adult Chinese living in Melbourne. Australia. This is a semi-quantitative questionnaire (MCHS-FFQ) and is designed to estimate past food intake. It consists of 220 foods and beverages. A reference portion is given to obtain a quantitative estimate of the usual intake portion. Various internal validation tests were performed. The MCHS-FFQ, being a food frequency dietary method, does not provide a good estimate of nutrients in foods which are not served in standard portions. such as sodium. The MCHS-FFQ offered a good estimate for potassium and protein intake when compared to estimates derived from a single 24-h urine collection. Finally, the MCHS-FFQ was predictive of plasma cholesterol levels. We conclude that the MCHS-FFQ is adequate for the assessment of individual usual food and nutrient intakes in a representative sample of adult Melbourne Chinese. For foods that are not served in a standard portion or quantifiable addition, an alternative more reliable method would be required for quantitative purposes. The method is. however, likely to be useful for the appraisal of overall food patterns in Chinese populations.