Critical review of the emerging research evidence on agricultural biodiversity, diet diversity, and nutritional status in low- and middle-income countries

Determinants of dietary diversity among women of reproductive age in two different agro-ecological zones of Rongai Sub-County, Nakuru, Kenya

Background

Empirical evidence on the link between agrobiodiversity and dietary diversity appears to be inconclusive. Thus, there arises a need to determine other factors that could significantly influence dietary diversity in different agro-ecological zones, as factors may vary from region to region.

Objective

The objective of this study was to document the status of agrobiodiversity and dietary diversity and to assess the determinants of dietary diversity among women of reproductive age in two different agro-ecological zones of Rongai Sub-County in Kenya.

Design

A cross-sectional study of 384 women aged 18-49 years was conducted. Agrobiodiversity was measured using the Shannon-Wiener index, species richness (count) and production diversity score. A 24-hour dietary recall was used to determine minimum dietary diversity for women (MDD-W) of reproductive age.

Results

Although the level of agrobiodiversity was different between the low and high agro-ecological zones (using Shannon-Wiener index); the women's dietary diversity was not different (p > 0.05) between low (3.78 ± 0.99) and high potential areas (3.84 ± 1.05). In multivariate logistic regression, there was no association (p > 0.05) between agrobiodiversity indicators and dietary diversity across the two agricultural zones. Factors influencing MDD-W in two agricultural zones were different. In low potential areas, woman's education level positively determined dietary diversity, while in high potential areas household gender, woman's education level, woman's age and family size influenced MDD-W.

Conclusion

The proportion of women who met minimum dietary diversity was low. Although agrobiodiversity was different in the two agro-ecological zones, women's dietary diversity scores were similar. In low agricultural potential areas, only education level influenced women's dietary diversity while household gender, education level, age and family size were the important determinants in high agricultural potential areas. Therefore, it is recommended that nutrition interventions focusing on lessening malnutrition and improving dietary quality should pay special attention to differences in agro-ecological zones to develop region-specific interventions instead of generalizing interventions.

Farm-Level Agricultural Biodiversity in the Peruvian Andes Is Associated with Greater Odds of Women Achieving a Minimally Diverse and Micronutrient Adequate Diet

Background

The extent to and mechanisms by which agricultural biodiversity may influence diet diversity and quality among women are not well understood.

Objectives

We aimed to 1) determine the association of farm-level agricultural biodiversity with diet diversity and quality among women of reproductive age in Peru and 2) determine the extent to which farm market orientation mediates or moderates this association.

Methods

We surveyed 600 households with the use of stratified random sampling across 3 study landscapes in the Peruvian Andes with diverse agroecological and market conditions. Diet diversity and quality among women were assessed by using quantitative 24-h dietary recalls with repeat recalls among 100 randomly selected women. We calculated a 10-food group diet diversity score (DDS), the Minimum Dietary Diversity for Women (MDD-W) indicator, probability of adequacy (PA) of 9 micronutrients by using a measurement-error model approach, and mean PA (MPA; mean of PAs for all nutrients). Agricultural biodiversity was defined as a count of crop species cultivated by the household during the 2016-2017 agricultural season.

Results

In regression analyses adjusting for sociodemographic and agricultural characteristics, farm-level agricultural biodiversity was associated with a higher DDS (incidence rate ratio from Poisson regression: 1.03; P < 0.05) and MPA (ordinary least-squares β-coefficient: 0.65; P < 0.1) and higher odds of achieving a minimally diverse diet (MDD-W: OR from logistic regression: 1.17; 95% CI: 1.11, 1.23) and a diet that met a minimum threshold for micronutrient adequacy (MPA >60%: OR: 1.21; 95% CI: 1.10, 1.35). Farm market orientation did not consistently moderate these associations, and in path analyses we observed no consistent evidence of mediation of these associations by farm market orientation.

Conclusions

Farm-level agricultural biodiversity was associated with moderately more diverse and more micronutrient-adequate diets among Peruvian women. This association was consistent across farms with varying levels of market orientation, although agricultural biodiversity likely contributed to diets principally through subsistence consumption.

Food and nutrient gaps in rural Northern Ghana: Does production of smallholder farming households support adoption of food-based dietary guidelines?

Food-based dietary guidelines (FBDGs) provide guidance to policy makers, the private sector and consumers to redesign food systems and to improve diets of vulnerable populations. As appropriate FBDGs are based on the actual dietary patterns and their costs, it is assumed that the recommended foods are available, affordable and acceptable for the population under study. Using quantitative dietary intake data of young children in rural Northern Ghana, we developed local FBDGs and studied whether these are supported by the diversity and quantity of the production of a household among 329 households. We found that 40% of rural Northern Ghanaian infants and young children were stunted and their nutrient intakes were far below the recommendations: the probability of adequacy for most nutrient intakes was less than 50%. At household level, the developed FBDGs were, on average, unable to sufficiently cover the household requirements for fat (60.4% of recommended nutrient intake (RNI)), calcium (34.3% RNI), iron (60.3% RNI), vitamin A (39.1% RNI), vitamin B12 (2.3% RNI) and vitamin C (54.6% RNI). This implies that even when these FBDGs are fully adopted the requirements for these nutrients will not be met. In addition, the nutrient needs and food needs (according to the developed FBDGs) of a household were only marginally covered by their own food production. The food production of over half the households supplied insufficient calcium (75.7%), vitamin A (100%), vitamin B12 (100%) and vitamin C (77.5%) to cover their needs. The food production of about 60% of the households did not cover their required quantities of grains and legumes and none covered their required quantities of vegetables. Further analysis of the food gaps at district and national level showed that sufficient grains were available at both levels (267% and 148%, respectively) to meet requirements; availability of legumes was sufficient at district level (268%) but not at national level (52%); and vegetables were insufficient at both levels (2% and 49%, respectively). Diversifying household food production is often proposed as a means to increase the diversity of foods available and thereby increasing dietary diversity of rural populations. We found that the diversity of the production of a household was indeed positively related with their food and nutrient coverage. However, the diversity of the production of a household and their food and nutrient coverage were not related with children's dietary diversity and nutrient adequacy. Our results show that the production of a households does not support the adoption of FBDGs in rural Northern Ghana, especially for vegetables. This suggests that the promotion of FBDGs through nutrition education or behaviour change communications activities alone is insufficient to lead to improvements in diets. Additional strategies are needed to increase the food availability and accessibility of the households, especially that of fruits and vegetables, such as diversification of the crops grown, increased production of specific crops and market-based strategies.

Nutrition education, farm production diversity, and commercialization on household and individual dietary diversity in Zimbabwe

Background

Nutrition education is crucial for improved nutrition outcomes. However, there are no studies to the best of our knowledge that have jointly analysed the roles of nutrition education, farm production diversity and commercialization on household, women and child dietary diversity.

Objective

This article jointly analyses the role of nutrition education, farm production diversity and commercialization on household, women and children dietary diversity in Zimbabwe. In addition, we analyze separately the roles of crop and livestock diversity and individual agricultural practices on dietary diversity.

Design

Data were collected from 2,815 households randomly selected in eight districts. Negative binomial regression was used for model estimations.

Results

Nutrition education increased household, women, and child dietary diversity by 3, 9 and 24%, respectively. Farm production diversity had a strong and positive association with household and women dietary diversity. Crop diversification led to a 4 and 5% increase in household and women dietary diversity, respectively. Furthermore, livestock diversification and market participation were positively associated with household, women, and children dietary diversity. The cultivation of pulses and fruits increased household, women, and children dietary diversity. Vegetable production and goat rearing increased household and women dietary diversity.

Conclusions

Nutrition education and improving access to markets are promising strategies to improve dietary diversity at both household and individual level. Results demonstrate the value of promoting nutrition education; farm production diversity; small livestock; pulses, vegetables and fruits; crop-livestock integration; and market access for improved nutrition.

Deforestation and child diet diversity: A geospatial analysis of 15 Sub-Saharan African countries

Deforestation worldwide could have important consequences for diet quality and human nutrition given the numerous ecosystem services that are provided by forests and biodiverse landscapes. Yet, empirical research assessing the links between deforestation and diets is lacking. In this study, we examined the association between deforestation and diet diversity among children using geolocated Demographic and Health Survey data for 33,777 children across 15 countries of sub-Saharan Africa coupled with remotely-sensed data on forest cover loss. Deforestation was negatively associated with diet diversity (regression coefficient (95% CI): - 0.47 (- 0.76, - 0.18)), as well as recent consumption of legumes and nuts, flesh foods, and fruits and vegetables among children aged 6 months to 24 months. Regionally, these trends were statistically significant only in the West Africa region. This hypothesis-generating research adds to the growing body of evidence that forests and forest-based ecosystems are associated with diet quality and nutrition and provides support for future studies that examine mechanisms linking forest loss and human nutrition.

Dietary species richness as a measure of food biodiversity and nutritional quality of diets

Biodiversity is key for human and environmental health. Available dietary and ecological indicators are not designed to assess the intricate relationship between food biodiversity and diet quality. We applied biodiversity indicators to dietary intake data from and assessed associations with diet quality of women and young children. Data from 24-hour diet recalls (55% in the wet season) of n = 6,226 participants (34% women) in rural areas from seven low- and middle-income countries were analyzed. Mean adequacies of vitamin A, vitamin C, folate, calcium, iron, and zinc and diet diversity score (DDS) were used to assess diet quality. Associations of biodiversity indicators with nutrient adequacy were quantified using multilevel models, receiver operating characteristic curves, and test sensitivity and specificity. A total of 234 different species were consumed, of which <30% were consumed in more than one country. Nine species were consumed in all countries and provided, on average, 61% of total energy intake and a significant contribution of micronutrients in the wet season. Compared with Simpson's index of diversity and functional diversity, species richness (SR) showed stronger associations and better diagnostic properties with micronutrient adequacy. For every additional species consumed, dietary nutrient adequacy increased by 0.03 (P < 0.001). Diets with higher nutrient adequacy were mostly obtained when both SR and DDS were maximal. Adding SR to the minimum cutoff for minimum diet diversity improved the ability to detect diets with higher micronutrient adequacy in women but not in children. Dietary SR is recommended as the most appropriate measure of food biodiversity in diets.