First-generation Ghanaian migrants in the UK; dietary intake, anthropometric indices and nutrition education through the Black churches

Background: Black Africans in developed countries have a higher prevalence of diet-related chronic diseases. However, dietary and anthropometry data is limited, particularly on sub-groups such as Ghanaians in the UK. Objectives: To determine the habitual diet and body composition of first generation Ghanaian migrants, to validate a food frequency questionnaire specific for Ghanaians, find the ideal body image of Ghanaians and the body size most attractive to Ghanaian males and to conduct a nutrition intervention programme using the Black Churches as a setting. Methodology: Cross-sectional survey. Participants were volunteers and first generation Ghanaian migrant who were congregants of Black Churches in London (n=288). Information on dietary intake was obtained from multiple repeated 24-hour recalls in a sub-sample (n=68) of the survey participants. The food frequency questionnaire was developed using the most commonly reported foods and portion sizes, field tested, shortened and then validated with multiple 24hr recalls (n=68). Information was also collected on height, weight, waist circumference, waist to hip ratio and percentage body fat which was measured using a portable bioelectric impedance analyzer (n=212). Participants from London (n=45) and Ghana (n=79) completed questionnaires to collect information on their ideal size and other body-shape related questions using the Figure Rating Scale (FRS). The nutrition intervention programme (n=76) was developed with input from participants through focus groups and the Obesity Clinic at the London Metropolitan University. Participants were assigned to either the intervention or control group and information on socio-demography, dietary intake and anthropometric measurements were taken at baseline, 6 weeks and at 3 months to evaluate the effectiveness of the intervention programme. Results: Energy and the percentage energy from fat intake of Ghanaian migrants (1987 kcal, fat 35.3%) was similar to that of the host population (1972kcal, fat 35.4%) but carbohydrate and fibre intake was different (carbohydrate 50.1%, fibre 16.4g vs 48.1%, 13.9g) for migrant Ghanaians and host population respectively. Energy under-reporting was 31% for this survey and was associated with gender and body mass index. The food frequency questionnaire performed well relative to 7 multiple 24-hour recalls with correlations increasing after adjusting for energy (protein r= 0.71, fat r=0.69, carbohydrate r=0.54, fibre r=0.69). Participants were correctly classified in the same (34%) or adjacent quartile (54%) for most nutrients with only 3% to 9% of participants mis-classified into opposite quartiles. Bland-Altman plots were within limits of agreement for all the macro-nutrients. The prevalence of overweight and obesity was higher in female migrant Ghanaians using body mass index (67%) compared to the host population (58%) but prevalence was lower when percentage body fat was used (female 40%). There was a cultural shift in acceptability of overweight and obese body sizes and shapes among Ghanaians with 60% of Ghanaian males preferring Ghanaian females with a normal body size. The nutrition intervention programme was conducted over 6 weeks and changes were observed in energy (intervention - 250kcal vs -135kcal (NS)) and fat intake (intervention -3.8g (p=0.04) vs control -2.1g (NS). Waist circumference decreased by 2.2cm (p=0.05) for the intervention group after 6 weeks. After 3 months fat intake decreased by 7.3g (p=0.000) for the intervention group and 10.4g (p=0.04) for the control group. Changes in anthropometry still persisted after 3 months for body weight (-2.3kg, p=0.001), body mass index (-1.4kg/m², p=0.001) waist circumference (-3.3cm, p=0.04) and % body fat (-2.0%, p=0.01) for the intervention group. Changes in anthropometry were also observed in the control group for weight (-0.9kg, p=0.05), waist circumference (-1.9cm, p=0.006) and waist-hip ratio (-0.1, p=0.03). Conclusion: The dietary intake of Ghanaian migrants in the UK is similar to the host population. The food frequency questionnaire developed specifically for this population is an adequate dietary assessment tool. Ghanaian males preferred females with normal body sizes. The prevalence of overweight and obesity is higher in female migrant Ghanaians compared to the host population and the Black Churches are an effective setting for the delivery of nutrition intervention programmes.