Potential contribution of cereal and milk based fermented foods to dietary nutrient intake of 1-5 years old children in Central province in Zambia

Zambia is still facing undernutrition and micronutrient deficiencies despite fortification and supplementation programmes stressing the need for additional solutions. Fermented foods have the potential to improve nutrient intake and, therefore, could have an important role in food based recommendations (FBRs) to ensure adequate intake of nutrients for optimal health of populations. Secondary dietary intake data was used in Optifood, a linear programming software to develop FBRs, for children aged 1–3 and 4–5 years in Mkushi district of Zambia. Three scenarios per age group were modeled to determine FBRs based on: (1) FBRs based on local available foods (2) FBR and Mabisi, a fermented milk beverage, and (3) FBR with Munkoyo, a cereal fermented beverage. The scenarios were compared to assess whether addition of Mabisi or Munkoyo achieved a better nutrient intake. FBRs based on only locally available non-fermented foods did not meet ≥70% of recommended nutrient intake (RNI) for calcium, fat, iron and zinc, so-called problem nutrients. The addition of Munkoyo to the FBRs did not reduce the number of problem nutrients, but after adding Mabisi to the FBR’s only iron (67% of RNI) in the 1–3 year age group and only zinc (67% of RNI) in the 4–5 year age group remained problem nutrients. Mabisi, a fermented milk product in combination with the local food pattern is a good additional source of nutrients for these age groups. However, additional nutrition sensitive and cost-effective measures would still be needed to improve nutrient intake, especially that of iron and zinc.</p

Children’s and adolescents’ rising animal-source food intakes in 1990–2018 were impacted by age, region, parental education and urbanicity

Animal-source foods (ASF) provide nutrition for children and adolescents’ physical and cognitive development. Here, we use data from the Global Dietary Database and Bayesian hierarchical models to quantify global, regional and national ASF intakes between 1990 and 2018 by age group across 185 countries, representing 93% of the world’s child population. Mean ASF intake was 1.9 servings per day, representing 16% of children consuming at least three daily servings. Intake was similar between boys and girls, but higher among urban children with educated parents. Consumption varied by age from 0.6 at <1 year to 2.5 servings per day at 15–19 years. Between 1990 and 2018, mean ASF intake increased by 0.5 servings per week, with increases in all regions except sub-Saharan Africa. In 2018, total ASF consumption was highest in Russia, Brazil, Mexico and Turkey, and lowest in Uganda, India, Kenya and Bangladesh. These findings can inform policy to address malnutrition through targeted ASF consumption programmes.publishedVersio

Incident type 2 diabetes attributable to suboptimal diet in 184 countries

The global burden of diet-attributable type 2 diabetes (T2D) is not well established. This risk assessment model estimated T2D incidence among adults attributable to direct and body weight-mediated effects of 11 dietary factors in 184 countries in 1990 and 2018. In 2018, suboptimal intake of these dietary factors was estimated to be attributable to 14.1 million (95% uncertainty interval (UI), 13.8–14.4 million) incident T2D cases, representing 70.3% (68.8–71.8%) of new cases globally. Largest T2D burdens were attributable to insufficient whole-grain intake (26.1% (25.0–27.1%)), excess refined rice and wheat intake (24.6% (22.3–27.2%)) and excess processed meat intake (20.3% (18.3–23.5%)). Across regions, highest proportional burdens were in central and eastern Europe and central Asia (85.6% (83.4–87.7%)) and Latin America and the Caribbean (81.8% (80.1–83.4%)); and lowest proportional burdens were in South Asia (55.4% (52.1–60.7%)). Proportions of diet-attributable T2D were generally larger in men than in women and were inversely correlated with age. Diet-attributable T2D was generally larger among urban versus rural residents and higher versus lower educated individuals, except in high-income countries, central and eastern Europe and central Asia, where burdens were larger in rural residents and in lower educated individuals. Compared with 1990, global diet-attributable T2D increased by 2.6 absolute percentage points (8.6 million more cases) in 2018, with variation in these trends by world region and dietary factor. These findings inform nutritional priorities and clinical and public health planning to improve dietary quality and reduce T2D globally.publishedVersio

Gradual emergence followed by exponential spread of the SARS-CoV-2 Omicron variant in Africa.

The geographic and evolutionary origins of the SARS-CoV-2 Omicron variant (BA.1), which was first detected mid-November 2021 in Southern Africa, remain unknown. We tested 13,097 COVID-19 patients sampled between mid-2021 to early 2022 from 22 African countries for BA.1 by real-time RT-PCR. By November-December 2021, BA.1 had replaced the Delta variant in all African sub-regions following a South-North gradient, with a peak Rt of 4.1. Polymerase chain reaction and near-full genome sequencing data revealed genetically diverse Omicron ancestors already existed across Africa by August 2021. Mutations, altering viral tropism, replication and immune escape, gradually accumulated in the spike gene. Omicron ancestors were therefore present in several African countries months before Omicron dominated transmission. These data also indicate that travel bans are ineffective in the face of undetected and widespread infection

Retraction.

This is a retraction of 'Gradual emergence followed by exponential spread of the SARS-CoV-2 Omicron variant in Africa' 10.1126/science.add873

Nutrition, health and microbial ecology of traditional fermented foods in Zambia

The widespread societal, development and health problem of undernutrition in many developing countries motivated my research described in this thesis. Despite past interventions and economic developments, many developing countries still face high levels of undernutrition; especially stunting (linear growth failure), deficiencies in zinc, vitamins A and B12, and folate, mainly in children under the age of five years. Some of the current and proposed interventions to improve nutritional status include dietary diversification, sugar fortification with vitamin A, high dose vitamin A capsule distribution to under five children twice every year, maize meal fortification, and others. Dietary diversification and improvement in the food preparation methods such as fermentation are potential means with potential to improve availability of nutrients especially for vulnerable populations. For this thesis, the focus is on Zambia, which is one of the most undernourished countries in the world, with 48% of the population considered undernourished. As Zambia is dependent on mainly maize as a staple food with lower consumption of animal food sources, diversification of diets presents an opportunity to combat undernutrition in this population. Within this, the traditional use of fermented foods presents an opportunity for improvement in nutrient intake in the population especially of children below the age of five years. My thesis explores this potential. My research has three central aims. (1) Elucidating the nutritional potential of the traditional fermented foods Mabisi and Munkoyo to complement the diet of vulnerable groups such as children under five years old (Chapter 2). (2) Determining the nutritional aspects and microbial composition of the target traditional fermented beverages Mabisi and Munkoyo and whether microbes influence the level of nutrients in the two products (Chapter 3). (3) Understanding the influence of the favourable bacteria in the products in shaping human gut microbiota towards more favourable composition and its impact on nutritional status (Chapters 4 and 5). In Chapter 2 I describe the potential contribution of Mabisi and Munkoyo to nutrient intake in children under the age of five years using Optifood, a linear programming software that was developed by WHO and partners. Secondary dietary intake data collected using 24-hour recall method was modeled to develop food based recommendations (FBRs), for children aged 1-3 and 4-5 years in Mkushi district of Zambia. Three scenarios per age group were modeled to determine weekly food-based recommendations based on: (1) food based recommendations with the local available foods, (2) food based recommendations with inclusion of Mabisi, a fermented milk beverage, and (3) food based recommendations with inclusion of Munkoyo, a cereal fermented beverage. The scenarios were compared to assess whether food based recommendations with the addition of Mabisi and/or Munkoyo achieved better nutrient intake. FBRs based on only locally available non-fermented foods did not meet ≥70% of recommended nutrient intake (RNI) for calcium, fat, iron and zinc. The addition of Munkoyo to the FBRs did not reduce the number of problem nutrients, but after adding Mabisi to the FBR’s only iron (67% of RNI) remained a problem nutrient in the 1-3 year age group and only zinc (67% of RNI) remained a problem nutrient in the 4-5 year age group. Mabisi, a fermented milk product in combination with the local food pattern is a good additional source of nutrients for these age groups. However, additional nutrition sensitive and cost-effective measures would still be needed to improve nutrient intake, especially that of iron and zinc. Chapter 3 describes the results obtained from laboratory analysis of Mabisi and Munkoyo samples collected during a cross sectional study in Mkushi to determine their nutritional composition and microbial communities. It was hypothesized that Mabisi and Munkoyo each contain distinct microbial communities and that nutritional composition depends on microbial composition. With respect to the variation in microbial community structure, I therefore addressed whether the use of different raw materials can explain the variation in the structure of microbial communities, and if variation in nutritional composition can be explained by differences in microbial community structure. Here, we characterized the nutritional composition and microbial community composition of Mabisi and Munkoyo. We found that the two products are different with respect to the nutritional and the microbial composition. Mabisi was found to have higher crude protein, fat, and carbohydrates than Munkoyo. The microbial community composition was also different for the two products, while both are dominated by lactic acid bacteria. Our analyses showed that variation in nutritional composition, defined as how much consumption would contribute to estimated average requirement (EAR), might be explained by variation in microbial community composition. Consumption of Mabisi appeared to contribute more to the estimated average requirement (% of EAR) and its inclusion in food based recommendations is warranted. We further found evidence that through fermentation of the raw materials (raw milk for Mabisi and cereal for Munkoyo), the levels of B-vitamins can increase. Levels of increase likely depend on the exact composition of the microbial community used for fermentation. Our results show the potential of Mabisi to add value to current diets and suggests that variations in microbial composition between specific product samples can result in variations in nutritional composition. The in vitro experiment in Chapter 4 of this thesis assesses the impact of Mabisi and Munkoyo on the gut microbiota focusing on the potential changes in metabolite profiles of gut microbiota taken from stool samples upon exposure to Mabisi and Munkoyo. The shifts in metabolite profiles were correlated to changes in abundance of a key indicator bacterium (Lactobacillus) for healthy gut microbiota composition. We exposed stool samples to these products and various controls and measured concentrations of short chain fatty acids (SCFAs) and used these as an indicator of beneficial bacteria activity and measured shifts in levels of the indicator beneficial bacterium Lactobacillus. Results show that exposure of the gut microbiota from stool to Mabisi and Munkoyo results in higher levels of SCFAs and also higher levels of Lactobacillus. These results support the idea that consumption of fermented foods can result in healthier metabolism of the gut microbiota as measured with SCFA concentrations. These results can inform further more complex in-vitro as well as in vivo studies on the effects of the traditional fermented foods on gut microbiota metabolism and composition. Chapter 5 describes a survey that was undertaken in Namwala and Mkushi to determine the effect of consuming traditional fermented foods on gut microbiota composition and nutritional status in children 6-24 months old in rural Zambia. Data on food consumption, morbidity and socio-demographic together with stool samples were collected from children aged 6-24 months residing in Namwala and Mkushi in Zambia. The stool samples were analysed for the composition of gut microbiota and for concentrations of short chain fatty acids (SCFAs) as a proxy for microbial metabolism. This data was then linked to data on intake of traditional fermented foods using multivariate analysis of variance. Gut microbiota of children who are fermented beverages consumers was associated with higher relative abundance of Bacteroides and Lactobacillus than the non-consumers. Higher levels of these bacterial groups have been associated with benefits to the host. There was no difference for the SCFA concentrations between the fermented foods consumers and non-consumers, which may be because other parts of the diets that we did not control for also contribute to SCFA production. The results imply that consumption of the two traditional fermented foods used in this study promotes a healthier gut microbiota composition in the children in Zambia. Our results warrant future more formal tests such as controlled human feeding trials to further validate our findings. In the framework of the work in this Thesis it is evident the two products are good sources of nutrients and have potential probiotic effects to confer better health and nutritional status to its consumers. The goal of contributing to improvement of people’s lives through dietary intake improvements using traditional fermented foods could be achieved as shown in this thesis. The work highlights the need to explore locally available and culturally accepted foods, more so the fermented foods such as Mabisi and Munkoyo in the fight against undernutrition. However further work to generate more evidence for the formalization of our products Mabisi and Munkoyo with key messages on benefits formulated for dissemination to the current and potential consumers. </p

Nutritional Composition and Microbial Communities of Two Non-alcoholic Traditional Fermented Beverages from Zambia: A Study of Mabisi and Munkoyo

Traditional fermented foods and beverages are common in many countries, including Zambia. While the general (nutritional) benefits of fermented foods are widely recognised, the nutritional composition of most traditional fermented foods is unknown. Furthermore, fermentation is known to add nutritional value to raw materials, mainly by adding B-vitamins and removing anti-nutritional factors. In the case of traditional fermentation, the composition of microbial communities responsible for fermentation varies from producer to producer and this may also be true for the nutritional composition. Here, we characterized the nutrient profile and microbial community composition of two traditional fermented foods: milk-based Mabisi and cereal-based Munkoyo. We found that the two products are different with respect to their nutritional parameters and their microbial compositions. Mabisi was found to have higher nutritional values for crude protein, fat, and carbohydrates than Munkoyo. The microbial community composition was also different for the two products, while both communities were dominated by lactic acid bacteria. Our analyses showed that variations in nutritional composition, defined as the amount of consumption that would contribute to the estimated average requirement (EAR), might be explained by variations in microbial community composition. Consumption of Mabisi appeared to contribute more than Munkoyo to the EAR and its inclusion in food-based recommendations is warranted. Our results show the potential of traditional fermented foods such as Mabisi and Munkoyo to add value to current diets and suggests that variations in microbial composition between specific product samples can result in variations in nutritional composition

Adequate Dietary Intake and Consumption of Indigenous Fermented Products Are Associated with Improved Nutrition Status among Children Aged 6–23 Months in Zambia

Agroecological food systems and socioeconomic characteristics are known to influence household food security and food consumption patterns and consequently have an impact on child nutritional status. The present study examined food consumption patterns among children aged 6–23 months in two geographic regions of Zambia, with special focus on consumption of fermented products, and its association with illnesses and nutritional status. The cross-sectional survey enrolled a total of 213 children from Namwala and Mkushi districts of Zambia. A 24 h recall and food frequency questionnaire (FFQ) were used to determine the number of food groups consumed and consequently dietary diversity scores and food consumption patterns, respectively. Determinants of child’s linear growth as measured by Height-for-Age Z-scores (HAZ) were assessed via multiple linear regression analysis. In total, 54% of the children met the minimum dietary diversity by consuming food from at least 5+ food groups. Maize meal porridge, Mabisi (fermented milk), Chibwantu and Munkoyo (fermented beverages based on cereals) and groundnuts were among the frequently consumed foods. A higher consumption of fermented beverages was observed in Namwala compared to Mkushi district. A significant association was observed between HAZ score (rho = 0.198, p = 0.004), Weight-for-Age Z-score (WAZ) (rho = 0.142, p = 0.039) and consumption of mabisi. Dietary intake had a positive association with child nutritional status. The frequent consumption of traditional non-alcoholic cereal and milk-based fermented foods underpinned their contribution to the children’s dietary intake. Moreover, the trend would be viewed as an indicator to nutrition and policy actors on possible unoptimized potential of indigenous fermented foods’ influence in nutritional and health status among children at regional and national levels. Although Zambia has a wide range of traditional non-alcoholic fermented food products, their prospects in provision of macro- and micronutrients along with microbiota benefits remain scanty despite global efforts increasingly advocating for the inclusion of such traditional foods in food-based recommendations