Fortified wheat flour and nutrient status in Cameroon
What it found
One year after fortified wheat flour was introduced in two Cameroonian cities, women and children had higher levels of iron, zinc, folate and vitamin B-12, and fewer were low in these nutrients.
The study compared surveys before and after the flour was fortified.
What they found
Studies in people
Folate levels rose sharply
Mean plasma folate was about 250% greater after fortification in women (47 compared with 15 nmol/L) and in children (56 compared with 20 nmol/L). The share of people with low plasma folate fell to less than 1% in both groups.
Vitamin B-12 levels higher
Mean plasma and breast-milk vitamin B-12 concentrations were more than 50% greater after fortification. The authors say this is the first evaluation of a large-scale flour fortification program on vitamin B-12 status.
Zinc deficiency less common
Mean plasma zinc was higher after fortification, and fewer women and children had low plasma zinc. In women, low zinc fell from 39% to 21%; in children, from 47% to 28%.
Iron status improved
After fortification, mean ferritin was higher and soluble transferrin receptor was lower in both women and children, suggesting better iron status. The prevalence of iron deficiency fell, but iron deficiency anemia did not differ between surveys.
Anemia in women
The prevalence of anemia among women was lower after fortification (39.1% compared with 46.7%). Among children, hemoglobin and anemia prevalence did not differ between the two surveys.
Other findings
Flour fortification levels
Of wheat flour samples collected, 76% were considered fortified, and the mean iron and zinc contents of fortified samples were close to the mandated amounts. Only 34% of samples met both the iron and zinc targets.
What the authors conclude
“Although the pre-post survey design limits causal inference, iron, zinc, folate, and vitamin B-12 status increased among women and children in urban Cameroon after mandatory wheat flour fortification.”
Also in their conclusions
- They conclude that iron, zinc, folate, and vitamin B-12 status increased among women and children in urban Cameroon after mandatory wheat flour fortification.
- They note that the pre-post survey design limits causal inference.
- They advise that the program should be evaluated in other regions of Cameroon where deficiencies were greatest, to inform adjustments to program design.
How it was done
Few data exist on whether large-scale food fortification programs actually improve micronutrient status in the people who need it most, such as women of reproductive age and young children. Information is especially scarce for zinc, vitamin B-12 and, in low-income settings, folate.
They ran two household surveys in Yaoundé and Douala, one in 2009 (2 years before fortified wheat flour was introduced) and one in 2012 (1 year after). Each survey selected 10 households in each of the same 30 clusters, and measured nutrient levels in women aged 15 to 49 and children aged 12 to 59 months.
What it can’t tell you
- The study compared surveys before and after fortification rather than following the same people over time, so it cannot prove that the fortification program caused the changes seen.
- Other unmeasured factors could have contributed to the differences between the two surveys.
- The results apply to women and children in Yaoundé and Douala and may not reflect what happens in other regions or groups.
Who paid
- Conflicts
- Author disclosures: LHA, SS-F, DH, DWK, M-MG, LAH, AF, and RAS, no conflicts of interest. RE-S, MN, AON, AT, and KHB received research funding from Sight and Life for the current study. RE-S received conference travel support from Sight and Life for an unrelated project.
- Authors work at
- University of California, CA; Agricultural Research Service Western Human Nutrition Research Center, CA; Children's Hospital Oakland Research Institute, CA
The paper
- Title
- Iron, Zinc, Folate, and Vitamin B-12 Status Increased among Women and Children in Yaoundé and Douala, Cameroon, 1 Year after Introducing Fortified Wheat Flour
- Type
- Study
- Evidence
- Studies in people
- Summarised from
- Full text
- Cite
- Engle-Stone R, Nankap M, Ndjebayi AO, et al (2017). Iron, Zinc, Folate, and Vitamin B-12 Status Increased among Women and Children in Yaoundé and Douala, Cameroon, 1 Year after Introducing Fortified Wheat Flour. The Journal of nutrition. doi:10.3945/jn.116.245076Free full textPubMed 28592513DOI
Summary written 26 Sep 2026. Check it against the paper before it changes what you eat. How we summarise papers · Report an error