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Supplementation of red palm olein-enriched biscuits improves levels of provitamin A carotenes, iron, and erythropoiesis in vitamin A-deficient primary schoolchildren: a double-blinded randomised controlled trial

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Abstract

Purpose

Vitamin A deficiency (VAD) remains a significant contributor to childhood morbidity and mortality in developing countries; therefore, the implementation of sustainable and cost-effective approaches to control VAD is of utmost pertinence. This study aims to investigate the efficacy of red palm olein (RPO)-enriched biscuit supplementation in improving vitamin A, haematological, iron, and inflammatory status among vitamin A-deficient schoolchildren.

Methods

We conducted a double-blinded, randomised controlled trial involving 651 rural primary schoolchildren (8–12 years) with VAD in Malaysia. The schoolchildren were randomised to receive either RPO-enriched biscuits (experimental group, n = 334) or palm olein-enriched biscuits (control group, n = 317) for 6-month duration.

Results

Significant improvements in retinol and retinol-binding protein 4 levels were observed in both groups after supplementation (P < 0.001). The improvement in retinol levels were similar across groups among subjects with confirmed VAD (P = 0.40). Among those with marginal VAD, greater improvement in retinol levels was recorded in the control group (P < 0.001) but lacked clinical significance. The levels of α- and β-carotenes, haematological parameters (haemoglobin, packed cell volume, mean corpuscular volume and mean corpuscular haemoglobin) and iron enhanced more significantly in the experimental group (P < 0.05). The significant reduction in the prevalence of microcytic anaemia (− 21.8%) and high inflammation (− 8.1%) was only observed in the experimental group.

Conclusion

The supplementation of RPO-enriched biscuits enhanced levels of provitamin A carotenes, iron, and erythropoiesis, and exhibited anti-inflammatory effects. Therefore, the incorporation of RPO into National Nutritional Intervention Programs may be a potential measure to improve the health status of vitamin A-deficient children, among various other interventions.

Clinical trial registration

ClinicalTrials.gov (NCT03256123).

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Data availability

The data that support the findings of this study are available on request from the corresponding authors, RL and YALL. The data are not publicly available due to their containing information that could compromise the privacy of research participants.

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Acknowledgements

We gratefully acknowledge the Ministry of Education (MOE), Ministry of Health (MOH), and Department of Orang Asli Development (JAKOA), the head of Orang Asli villages (Tok Batin), school principals, and teachers for permitting to conduct sample and data collections from the schoolchildren. Special acknowledgement to Assoc. Prof. Dr. Khang Tsung Fei and Ms. Lim Kah Xuan from Universiti Malaya for the consultation in statistical analysis. We would also like to express our deepest appreciation to Carotino Sdn Bhd., Noraini’s Cookies Worldwide Sdn. Bhd., doctors, medical assistants, nurses, MPOB research assistants, and internship students for their assistance and support throughout the study. Most importantly, we thank all the schoolchildren and their parents for their voluntary participation in this study.

Funding

The study was supported by the RMK-11 (Eleventh Malaysia Plan) Grant (PD219/16), which managed by Malaysian Palm Oil Board. This research was supported (in part) by the Intramural Research Program of the NIH, National Institute of Allergy and Infectious Diseases (NIAID).

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Authors and Affiliations

  1. Nutrition Unit, Division of Product Development and Advisory Services, Malaysian Palm Oil Board, No. 6, Persiaran Institusi, Bandar Baru Bangi, 43000, Kajang, Selangor, Malaysia

    Pei Yee Tan, Radhika Loganathan, Kim-Tiu Teng & Kanga Rani Selvaduray

  2. Department of Parasitology, Faculty of Medicine, Universiti Malaya, 50603, Kuala Lumpur, Malaysia

    Pei Yee Tan, Syahirah Nadiah Mohd Johari, Romano Ngui & Yvonne Ai-Lian Lim

  3. Type 2 Immunity Section, Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Diseases, National Institute of Health, Bethesda, MD, USA

    Soo Ching Lee

  4. Department of Paraclinical Sciences, Faculty of Medicine & Health Sciences, Universiti Malaysia Sarawak, 94300, Kota Samarahan, Sarawak, Malaysia

    Romano Ngui

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  1. Pei Yee Tan
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Contributions

RL, KTT, YALL and SCL contributed to the design of this study. RL, KTT and KRS were involved in the funding acquisition. PYT and SNMJ were involved in the data collection. PYT performed the data analyses and wrote the manuscript. PYT, RL, KTT, YALL, SCL, RN and KRS reviewed and edited the manuscript. All the authors read, revised critically and approved the final manuscript.

Corresponding authors

Correspondence to Radhika Loganathan or Yvonne Ai-Lian Lim.

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Conflict of interest

P.Y.T, K.T.T., R.L. and K.R.S are employees of the Malaysian Palm Oil Board, which received and managed grant RMK-11 (Eleventh Malaysia Plan) Grant-PD219/16 (public funding) and conducted the study. The other authors declare no conflict of interest.

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Tan, P.Y., Loganathan, R., Teng, KT. et al. Supplementation of red palm olein-enriched biscuits improves levels of provitamin A carotenes, iron, and erythropoiesis in vitamin A-deficient primary schoolchildren: a double-blinded randomised controlled trial. Eur J Nutr 63, 905–918 (2024). https://doi.org/10.1007/s00394-023-03314-6

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