The longstanding global crisis of childhood undernutrition

For years, global efforts to reduce childhood undernutrition have focused on the idea that “what you are is what you eat.” This approach has led to initiatives like promoting exclusive breastfeeding and improving sanitation and hygiene, backed by organizations like the World Health Organization (WHO). However, despite these efforts, the rates of childhood undernutrition worldwide have not dropped as expected^[1]. This shows that we need new, innovative ways to strengthen existing programs and better support children’s health.

One major reason why childhood undernutrition remains a problem is due to enteric infections—infections that affect the intestines. Diarrhoea is one of the most common consequences of enteric infections, and it often leads to a cycle where children lose nutrients, feel less hungry, and cannot absorb nutrients properly, resulting in malnutrition^[2]. In areas with poor sanitation and hygiene, children are also exposed to harmful microbes, which can cause a condition called environmental enteric dysfunction. This condition, which can be acquired as early as 12 weeks of age, damages the intestines, making it harder for children to digest and absorb nutrients^[3].

Gut Health: The key to prevention

To prevent both enteric infections and undernutrition, we need to keep the intestines healthy. Interestingly, scientists are now looking at how probiotics (beneficial bacteria) and prebiotics (compounds that feed beneficial bacteria) can play a role in improving gut health and preventing infections. Probiotics are live microorganisms, often bacteria, that, when consumed in adequate amounts, can have a positive effect on health. Prebiotics, usually types of fibre, act as food for these good bacteria. Synbiotics combine both probiotics and prebiotics to support gut health.

In high-income countries, probiotics have been used for years to treat and prevent various childhood conditions, like diarrhoea and premature birth complications^[4]. These beneficial bacteria work by improving the gut microbiota—the community of microbes living in our intestines. When we consume probiotics, they help increase the number of good bacteria, which compete with harmful pathogens for space in the gut. They also help digest food and produce acids that fight off bad bacteria, boost the growth of healthy intestinal cells, and support the immune system.

The future of gut health in fighting undernutrition

Most research so far on probiotics has focused on children who are already sick or older children. However, there is a growing interest in using probiotics from early childhood to help build a stronger, healthier gut from the start. Early studies, particularly in sub-Saharan Africa, are exploring whether giving probiotics to infants can improve their growth, development, and overall health. These studies suggest that the health of our intestines is just as important as the food we eat when it comes to fighting undernutrition^[5].

In short, for children to fully process and utilize the nutrients in the food they eat, their intestines must always be strong and healthy. By improving gut health through probiotics, we could help children grow stronger, fight infections more effectively, and ultimately reduce the rates of childhood undernutrition.

By ISID Emerging Leaders, Benjamin Kadia and Tintu Varghese

References

1. Scott N, Delport D, Hainsworth S, Pearson R, Morgan C, Huang S, et al. Ending malnutrition in all its forms requires scaling up proven nutrition interventions and much more: a 129-country analysis. BMC Med. 2020;18(1):356.
2. Rodriguez L, Cervantes E, Ortiz R. Malnutrition and gastrointestinal and respiratory infections in children: a public health problem. Int J Environ Res Public Health. 2011;8(4):1174-205.
3. Naylor C, Lu M, Haque R, Mondal D, Buonomo E, Nayak U, et al. Environmental Enteropathy, Oral Vaccine Failure and Growth Faltering in Infants in Bangladesh. EBioMedicine. 2015;2(11):1759-66.
4. Alcon-Giner C. Microbiota Supplementation with Bifidobacterium and Lactobacillus Modifies the Preterm Infant Gut Microbiota and Metabolome: An Observational Study. Cell Reports Medicine 2020.
5. Momo Kadia B, Otiti MI, Ramsteijn AS, Sow D, Faye B, Heffernan C, et al. Modulating the early-life gut microbiota using pro-, pre-, and synbiotics to improve gut health, child development, and growth. Nutr Rev. 2023.