OBJECTIVE -Rates of non-insulin-dependent diabetes mellitus have risen sharply in recent years among blacks in the U.S. and the U.K. Increases in risk have likewise been observed in the island nations of the Caribbean and in urban West Africa. To date, however, no systematic comparison of the geographic variation of NIDDM among black populations has been undertaken. RESEARCH DESIGN AND METHODS-In the course of an international collaborative study on cardiovascular disease, we used a standardized protocol to determine the rates of NIDDM and associated risk factors in populations of the African diaspora. Representative samples were drawn from sites in Nigeria, St. Lucia, Barbados, Jamaica, the United States, and the United Kingdom. A total of 4,823 individuals aged 25-74 years were recruited, all sites combined.RESULTS -In sharp contrast to a prevalence of 2% in Nigeria, age-adjusted prevalences of self-reported NIDDM were 9% in the Caribbean and 11% in the U.S. and the U.K. Mean BMI ranged from 22 kg/m 2 among men in West Africa to 31 kg/m 2 in women in the U.S. Disease prevalence across sites was essentially collinear with obesity, pointing to site differences in the balance between energy intake and expenditure as the primary determinant of differential NIDDM risk among these populations.CONCLUSIONS -In ethnic groups sharing a common genetic ancestry, these comparative data demonstrate the determining influence of changes in living conditions on the population risk of NIDDM.

Background: An interviewer-administered quantitative food-frequency questionnaire (FFQ) was developed to determine the energy and nutrient intakes of adult Jamaicans of African origin as part of a study of the epidemiology of diabetes and hypertension. Methods: Reproducibility of the questionnaire was investigated in 123 participants aged 25±74 years. The relative validity of the FFQ was assessed against twelve 24-hour recalls administered over 12 months in 73 of the participants. In addition, energy intakes (EI) were compared with estimated basal metabolic rates (BMR). Results: Reproducibility correlation coefficients (Pearson and intraclass) varied between 0.42 for retinol and 0.71 for carbohydrate, with most values falling between 0.50 and 0.60. When compared with repeated 24-hour recalls, the FFQ estimated slightly higher energy (mean 6%) and macronutrient intakes (mean 2±14%), and was within 5% when expressed as a percentage of energy intake. Micronutrients were higher by 1.19 (calcium) to 1.61 times (vitamin C). Unadjusted correlations between the FFQ and the reference method ranged from 0.20 for beta-carotene to 0.86 for alcohol. Cross-classification of nutrients into quartiles showed that 46±48% of participants in the lowest and highest quartiles were jointly classified by both methods. Misclassifications were low for most nutrients with one or two persons misclassified at the extreme quartiles. EI/BMR ratios suggested light to moderate activity levels appropriate for an urban population in a developing country. Conclusions: The FFQ showed reasonable reproducibility and validity and is suitable for estimating the habitual intakes of energy and macronutrients, but was poor for some micronutrients (retinol and beta-carotene). Keywords Dietary assessment Adult African originThe assessment of diet as a risk factor is central to the investigation of the epidemiology of the chronic diseases of diabetes, hypertension and obesity. Elucidation of diet±disease relationships requires dietary assessment methods that adequately describe and quantify intake, minimise systematic error and provide reasonably precise estimates of variability between individuals and/or groups 1 . The food-frequency questionnaire (FFQ) has become a widely used tool to measure usual consumption of nutrient intakes in epidemiological studies. This method of dietary assessment was developed to measure the variance in dietary intakes and rank participants according to levels of consumption, rather than to provide estimates of absolute quantities of energy and nutrient intakes 1,2 . Some investigations show that the method provides equally accurate estimates of both group and individual intakes 1,3±5 , while others suggest that foodfrequency data can only measure the consumption of groups 6 . Widespread use of the technique has been attributed also to its relative ease of administration, coding and analysis, thereby incurring lower cost of collecting and processing when compared with other methods of dietary assessment.Reliability is de...

Objectives:To identify lessons from and gaps in research on diet-disease links among former migrants in the United Kingdom (UK).Results:Migrant status and self-identified ethnicity do not match so these terms mask differences in social, nutritional and health status within and between population groups. Some former migrants differ in causes of death from the general population, e.g.: fewer coronary heart disease deaths among Caribbean-born; fewer cancer deaths among Caribbean, South Asian- and East African-born adults. Irish- and Scottish-born have higher mortality from all causes. Experience of risk factors differ also, e.g.: higher prevalences of hypertension and diabetes in Caribbean- and South Asian-born adults than representative samples of the general population; obesity and raised waist-hip circumference ratios in South Asian, African-Caribbean and some Irish-born adults. Former migrants experience long-term disadvantage, associated with more self-defined illness and lower reported physical activity. Nutrient intake data from the few, recent, small-scale studies must be interpreted with caution due to methodological diversity. However, second generation offspring of former migrants appear to adopt British dietary patterns, increasing fat and reducing vegetable, fruit and pulse consumption compared with first generation migrants.Conclusions:There is insufficient evidence on why some former migrants but not others experience lower specific mortality than the general population. Dietary intake variations provide important clues particularly when examined by age and migration status. Majority ethnic and younger migrant groups could raise and sustain high fruit and vegetable intakes but lower proportions of fat, by adopting many dietary practices from older migrants. Objective measures of physical activity and longitudinal studies of diets among different ethnic groups are needed to explain diversity in health outcomes and provide for evidence-based action.

Objective: To evaluate the habitual diet of a rural and urban population in Cameroon, Central Africa. Setting: An urban areaÐCite  Verte Housing District, Yaounde  (1058 subjects); and a rural areaÐthree villages in Evodoula, Cameroon (746 subjects). Subjects: Cameroonian men and women of African origin (1058 urban, and 746 rural), aged 24±74 y. Methods: The habitual diet was estimated with an interviewer-administered food frequency questionnaire. Main outcome measures: Macro-and micronutrient intake. Results: The intake of energy, fat and alcohol was higher in rural men and women than in urban subjects. In rural women, the intake of carbohydrates and protein was also higher. The intakes of ®bre, iron, carotene, zinc, potassium, and of the vitamins C, D and E were all higher in rural men and women than in their urban counterparts. The intake of retinol was lower in rural subjects than in urban subjects. Eight of the 10 foods eaten in the highest amount and contributing most to energy intake differed between the rural and urban population. Conclusion: The habitual diet in rural Cameroon contains more fat and alcohol than the diet in urban Cameroon. The high physical activity in the rural area may explain the lower levels of the cardiovascular risk factors in this area compared to those of the urban dwellers.

Objective To determine the prevalence of common mental disorders (anxiety and depression) and help seeking behaviour in African Caribbeans and white Europeans. Design Two phase survey in a general population sample. The first phase comprised screening with the 12 item general health questionnaire; the second phase was standardised psychiatric assessment and interview about help seeking. Setting People registered with four general practices in central Manchester. Participants Of 1467 people randomly selected from family health services authority lists, 864 were still resident. 337 African Caribbeans and 275 white Europeans completed the screening phase (response rate 71%); 127 African Caribbeans and 103 white Europeans were interviewed in the second phase. Main outcome measures One month period prevalence of anxiety and depressive disorders in each ethnic group. Results 13% of African Caribbeans (95% confidence interval 10% to 16%) and 14% (10% to 18%) of white Europeans had one or more disorder. Anxiety disorders were significantly less common among African Caribbeans (3% (1% to 5%) v 9% (6% to 12%) in white Europeans). Depressive disorders were significantly more common among African Caribbean women than white women (difference 8% (1% to 15%)). Medical help seeking was similar in the two groups, but African Caribbeans with mental disorders were more likely to seek additional help from non-medical sources (12/29 v 5/29, P = 0.082). Conclusions In an inner city setting the prevalence of common mental disorders is similar in these two ethnic groups.