Dietary patterns in Tanzania's transitioning rural and urban areas.

Background: Like other Sub-Saharan Africa (SSA) countries, Tanzania is undergoing socio-economic changes that impact lifestyles and dietary choices. Traditionally, differences in dietary habits between rural and urban areas in Tanzania and other SSA countries were prominent. However, recent research indicates converging lifestyles and dietary choices associated with increased risk of cardiometabolic diseases. The objective of the current study was hence to investigate differences and similarities in dietary patterns, energy, and food groups intake in urban and rural Tanzania.

Methods: Dietary habits were assessed by use of a Food Frequency Questionnaire (FFQ) for 442 respondents aged 44-65 years in urban (Ubungo -Dar es Salaam) and rural (Kilindi- Tanga) districts of Tanzania. Dietary patterns were determined using Principal Components Analysis (PCA). Bivariate analyses identified determinants of dietary patterns in urban and rural Tanzania.

Results: Two dietary patterns, a "mixed pattern" characterized by whole grains, potatoes, fruits, vegetables, meat, fried potatoes and tubers, alcohol, sugar-sweetened beverages (SSB), sugar and sweets, and added oils and a "plant-rich pattern" characterized by whole grains, fruits, pulses and peas, seasoning vegetables and salads, SSB, sugar and sweets, and added oils were identified. Urban residents contributed more to the mixed pattern, while rural residents had a higher contribution to the plant-rich pattern. Overall, dietary diversity was greater in urban than rural Tanzania. The estimated median daily energy intake was 2,902 kcal (IQR: 1449.2) with a lower energy intake in rural (2,817 kcal, IQR: 1,274) as compared to urban residents (3,052 kcal, IQR: 1558) (p = 0.021). The percent contribution to the median average daily energy intake for grains, fruits, and milk was higher in rural than urban participants. No differences were observed for meat, poultry and eggs.

Conclusion: We identified two distinct dietary patterns: a "mixed pattern" prominent in urban and a "plant-rich pattern" more common in rural. Urban diets were more diverse with slightly higher energy intake. These findings underscore the effects of urbanization on diets and the need for targeted nutritional intervention for both rural and urban populations.