To assess the potential contribution of large-scale food fortification (LSFF) towards meeting dietary micronutrient requirements in Tanzania.

We used household food consumption data from the National Panel Survey 2014–15 to estimate fortifiable food vehicle coverage and consumption (standardised using the adult female equivalent approach) and the prevalence at risk of inadequate apparent intake of five micronutrients included in Tanzania’s fortification legislation. We modelled four LSFF scenarios: no fortification, status quo (i.e. compliance with current fortification contents) and full fortification with and without maize flour fortification.

Tanzania.

A nationally representative sample of 3290 Tanzanian households.

The coverage of edible oils and maize and wheat flours (including products of wheat flour and oil such as bread and cakes) was high, with 91 percent, 88 percent and 53 percent of households consuming these commodities, respectively. We estimated that vitamin A-fortified oil could reduce the prevalence of inadequate apparent intake of vitamin A (retinol activity equivalent) from 92 percent without LSFF to 80 percent with LSFF at current fortification levels. Low industry LSFF compliance of flour fortification limits the contribution of other micronutrients, but a hypothetical full fortification scenario shows that LSFF of cereal flours could substantially reduce the prevalence at risk of inadequate intakes of iron, zinc, folate and vitamin B12.

The current Tanzania LSFF programme likely contributes to reducing vitamin A inadequacy. Policies that support increased compliance could improve the supply of multiple nutrients, but the prominence of small-scale maize mills restricts this theoretical benefit.

To review existing publications using Household Consumption and Expenditure Survey (HCES) data to estimate household dietary nutrient supply to (1) describe scope of available literature, (2) identify the metrics reported and parameters used to construct these metrics, (3) summarise comparisons between estimates derived from HCES and individual dietary assessment data and (4) explore the demographic and socio-economic sub-groups used to characterise risks of nutrient inadequacy.

This study is a systematic review of publications identified from online databases published between 2000 to 2019 that used HCES food consumption data to estimate household dietary nutrient supply. Further publications were identified by ‘snowballing’ the references of included database-identified publications.

Publications using data from low- and lower-middle income countries.

In total, fifty-eight publications were included. Three metrics were reported that characterised household dietary nutrient supply: apparent nutrient intake per adult-male equivalent per day (n 35), apparent nutrient intake per capita per day (n 24) and nutrient density (n 5). Nutrient intakes were generally overestimated using HCES food consumption data, with several studies finding sizeable discrepancies compared with intake estimates based on individual dietary assessment methods. Sub-group analyses predominantly focused on measuring variation in household dietary nutrient supply according to socio-economic position and geography.

HCES data are increasingly being used to assess diets across populations. More research is needed to inform the development of a framework to guide the use of and qualified interpretation of dietary assessments based on these data.

To utilize complementary biochemical and dietary data collected before the initiation of national flour fortification to (i) identify micronutrient insufficiencies or deficiencies and dietary inadequacies in Palestinian women and children in vulnerable communities and (ii) assess the suitability of the current wheat flour fortification formula.

Quantitative dietary intake questionnaires were administered and fasting venous blood samples collected in randomly selected households in Gaza City and Hebron. The impact of fortification was simulated by estimating the additional micronutrient content of fortified wheat flour.

Households in Gaza City and Hebron that were not receiving food aid from social programmes.

Non-pregnant women (18–49 years) and children aged 36–83 months.

The micronutrients with highest prevalence of insufficiency were vitamin D in women (84–97 % with serum 25-hydroxyvitamin D <50 nmol/l) and vitamin B12 in women and children (43–82 % with serum B12 <221 pmol/l). Deficiencies of vitamin A, Fe and Zn were also of public health concern. Current levels of wheat flour fortificants were predicted to improve, but not eliminate, micronutrient intake inadequacies. Modification of fortificant concentrations of vitamin D, thiamin, vitamin B12, Zn and folic acid may be indicated.

Micronutrient insufficiencies or deficiencies and intake inadequacies were prevalent based on either biochemical or dietary intake criteria. Adjustments to the current fortification formula for wheat flour are necessary to better meet the nutrient needs of Palestinian women and children.