Women in Selected Communities of Punjab, India Have a High Prevalence of Iron, Zinc, Vitamin B12, and Folate Deficiencies: Implications for a Multiply-Fortified Salt Intervention

Dietary intake and biomarkers of micronutrient status of 100 non-pregnant women of reproductive age (NPWRA) were assessed to determine optimal levels of iron, zinc, vitamin B12, and folic acid to include in multiply-fortified salt (MFS) that will be evaluated in an upcoming trial. Weighed food records were obtained from participants to measure intake of micronutrients and discretionary salt, and to assess adequacy using Indian Nutrient Reference Values (NRVs). Statistical modeling was used to determine optimal fortification levels to reduce inadequate micronutrient intake while limiting intake above the upper limit. Fasting blood samples were obtained to assess iron, zinc, vitamin B12, and folate status. In usual diets, inadequate intake of iron (46%), zinc (95%), vitamin B12 (83%), and folate (36%) was high. Mean intake of discretionary salt was 4.7 g/day. Prevalence estimates of anemia (37%), iron deficiency (67%), zinc deficiency (34%), vitamin B12 insufficiency (37%), and folate insufficiency (70%) were also high. Simulating the addition of optimized MFS to usual diets resulted in percentage point (pp) reductions in inadequate intake by 29 pp for iron, 76 pp for zinc, 81 pp for vitamin B12, and 36 pp for folate. MFS holds potential to reduce the burden of micronutrient deficiencies in this setting.

Quintuply-fortified salt for the improvement of micronutrient status among women of reproductive age and preschool-aged children in Punjab, India: protocol for a randomized, controlled, community-based trial

Background

Multiple micronutrient (MN) deficiencies remain highly prevalent among women of reproductive age (WRA) and preschool-aged children (PSC) in many areas within India. Salt is an attractive vehicle for MN fortification in this context, as it is universally consumed in fairly consistent amounts and coverage of iodized salt (IS) is 94%. The overall objective of this trial is to evaluate the nutritional impact of quintuply-fortified salt with iron in the form of encapsulated ferrous fumarate, zinc, vitamin B12, folic acid, and iodine (eFF-Q5S) vs. quintuply-fortified salt with iron in the form of ferric pyrophosphate plus EDTA, zinc, vitamin B12, folic acid, and iodine (FePP-Q5S) vs. IS for the improvement of MN status among non-pregnant WRA and PSC.

Methods

The study is a community-based, randomized, controlled trial that will be conducted in Punjab, India. 780 non-pregnant WRA 18–49 years old and 468 PSC 12–59 months old will be enrolled and assigned to one of three intervention groups. Salt will be provided to participants monthly for 12 months. Primary outcomes include changes in mean concentration of biomarkers of iron, zinc, vitamin B12, folate and iodine. Secondary outcomes include changes in the composition of the gut microbiome, and discretionary salt intake of PSC.

Discussion

If proven efficacious, multiply-fortified salt (MFS) has the potential to drastically reduce the burden of MN deficiencies in India, and around the world. Although effectiveness research will be needed to examine the impact of MFS under programmatic conditions, salt fortification will piggy-back on existing platforms to produce IS and doubly-fortified salt (DFS), making it possible to scale-up the intervention quickly.

Trial registration

Clinicaltrials.gov: NCT05166980; date of registration: December 22, 2021. Clinical Trials Registry-India: CTRI/2022/040332 and CTRI/2022/02/040333; date of registration: February 15, 2022.

Comparison of Methods for Estimating Discretionary Salt Intake in Field Settings

Objectives

Accurate and precise estimates of discretionary salt (DS) intake are critical for designing salt fortification interventions and counseling on salt intake reduction. This study compared four methods of estimating DS intake among non-pregnant women of reproductive age (NPWRA) in northern India to inform the design of a trial of multiply-fortified salt.

Methods

Participants were NPWRA (18–49 y) in Punjab, India. Weighed food records (WFR), same-day duplicate diet (DD) composites, and samples of household (HH) salt were collected simultaneously from 100 women and repeated on a subset of 40. Sodium (Na) and iodine contents of the DD composites were analyzed using Inductively Coupled Plasma (ICP)-Optical Emission Spectrometry and ICP-Mass Spectrometry. HH salt samples were also analyzed for iodine. Methods for estimating DS intake included: 1) WFR: DS consumed from recipes or added at time of consumption were weighed; 2) HH salt disappearance (HHSD): total DS used by HH on the observation day divided by number of HH members; 3) Sodium estimation (NaE): Na content of 40 replicate DD composites prepared without DS were subtracted from the Na content of the corresponding original DD and difference multiplied by the molar mass of NaCl; 4) Iodine method (IM): analyzed iodine content of milk and milk products and commercial snacks were subtracted from DD iodine content, and difference divided by the iodine content of the HH's salt sample. The relations between methods were explored using Pearson correlation and Bland Altman analyses.

Results

Mean ± SD intake of DS according to the WFR, HHSD, and NaE methods were 4.7 ± 1.8 g/d, 5.8 ± 3.3 g/d, and 4.1 ± 2.1 g/d, respectively. Results of IM are pending. Pearson correlation coefficients for DS intake estimates obtained from WFR vs. NaE and WFR vs. HHSD were 0.82 (p < 0.001) and 0.48 (p < 0.001), respectively. Mean ± SD bias (limits of agreement) were 0.68 ± 1.25 g/d (−1.77, 3.13) for WFR vs. NaE, and 1.8 ± 2.93 g/d (−4.56, 6.92) for HHSD vs. WFR methods.

Conclusions

Discretionary salt intake from WFR and NaE showed good agreement and are feasible to implement in field settings.

Funding Sources

Bill & Melinda Gates Foundation.