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Tackling malnutrition with microorganisms
There are good microbes in the gut that aid digestion and keep us healthy and well-nourished.Siddhartha Hamal Dhakal
It would be an unpleasant experience for most of us if our vision were to be more than 20 times as powerful as it is now. Because at this visual strength, we can start seeing bacteria in our foods, cell phones, hands—almost everywhere. Microorganisms, or microbes, are small living creatures that are invisible to the unaided eye. These critters are not just around us, but inside us and in vast numbers.
Studies have estimated that there are as many microbes in the human body as our own cells. A large chunk of these microbes reside in our guts, and they are collectively called the gut microbiota, gut microbiome or gut flora. Microbes from the mother and the environment start colonising an infant’s gut during and right after birth. Some of these microbes are not harmful; they are rather vital for physiological development. As the baby matures, these microbes mature as well. A decade of scientific research has shown that failure to attain this microbial maturity could lead to severe childhood malnutrition.
In a study published in the journal Science a few months ago, it was reported that a particular combination of foods could nurture beneficial microbes in the guts of malnourished children. In contrast, the conventional diets used for food aids fail to do so. This might be the reason why malnourished children worldwide fail to recover completely, even after being adequately fed.
A team of researchers from the United States engineered mice and piglets in labs whose gut microbial communities resembled those of malnourished children. Then, they devised food prototypes that could repair the gut microbiome of these animals, along with tracking other indicators of healthy growth. Once the microbiome friendly food was formulated, the scientists wanted to figure out whether these same foods would enrich beneficial microbes in the guts of malnourished children. Thus, a clinical trial was conducted in Bangladesh, where three treatment groups received several combinations of newly formulated microbiome friendly foods. Another group received conventional foods commonly used to treat malnutrition.
The month-long feeding study showed that food which contained banana and a flour mix of chickpeas, soy and peanut fostered the right gut microbes and increased levels of critical proteins and metabolites necessary for proper bone formation, neurodevelopment and immune function. However, regular food which contained rice and milk (even eggs) did little to increase the levels of helpful bacterial strains.
The aforementioned study, also listed in the Science 2019 Breakthrough of the Year, is quite relevant in the context of our country. An estimated 2 million children under the age of five in Nepal—approximately 7 percent of the entire population—suffer from some form of undernutrition. Thanks to the initiatives led by various governmental and non-governmental organisations, substantial improvements have been made in reducing childhood malnutrition over the past two decades. However, the current number is still alarming. If these malnourished children do not fully recover, they will less likely be capable of making contributions to the active workforce in the future. This could stifle the nation’s economic productivity and development even further.
Although long-term clinical studies are underway to evaluate the role of microbiota targeted foods, there is a clearer scientific understanding regarding the role of gut flora and overall health. There is increasing scientific evidence that shows gut microbiota as a better predictor of diseases than our genetic makeup. Various studies have linked gut microbiome to several conditions such as arthritis, autism or Parkinson’s, to name a few. They have also been found to communicate with our brains, likely affecting our mood, anxiety, cognition and pain. Considering their vast potential, microbiome-based therapeutics and diagnostics may soon become a big part of modern medicine.
Although microbial communities in the gut change over the lifetime of an individual, the stage is set during the earliest years after birth. Since malnourished children have immature gut microbiome, they cannot completely digest and absorb all the nutrients provided to them. Therefore, even foods rich in nutrition, such as those formulated according to the standard set by the World Health Organisation, may not fully benefit malnourished children. In some cases, broad range antibiotics are given to severely malnourished children to kill pathogens in their guts. However, this can make the guts unhealthier because antibiotics also kill helpful gut bacteria, which could be harder to replenish. Hence, foods or medicines should be administered with the knowledge of how they affect the diversity of the gut flora.
Organisations working on this front, such as UNICEF or Action Against Hunger, should strongly consider using microbiota-directed complementary foods that are the result of exhaustive scientific research. Since these food supplements are culturally acceptable, readily available and affordable, they can easily fit within the goals of these organisations to tackle malnutrition. Also, the government should take notice of the scientific findings and make policies on nutrition accordingly.
Various factors such as environment, delivery mode, maternal microbiota and genetics affect the diversity of gut flora. Thus, malnourished children in Nepal could have slightly different microbiomes compared to those in Bangladesh (where the clinical studies were conducted). While the already formulated microbiome-friendly food would still be effective, this presents an additional opportunity for researchers at home to characterise the microbial communities specific to malnourished children in Nepal, and then work towards formulating foods particular to our regions which could enhance healthy gut microbiome.