When a pandemic and an epidemic collide: COVID-19, gut microbiota, and the double burden of malnutrition

Abstract

Background It is estimated that the COVID-19 pandemic will drastically increase all forms of malnutrition. Of particular concern, yet understated, is the potential to increase the double burden of malnutrition (DBM) epidemic. This coexistence of undernutrition together with overweight and obesity, or diet-related non-communicable disease (NCD), within low- to middle-income countries (LMICs) is increasing rapidly. Although multiple factors contribute to the DBM, food insecurity (FI) and gut microbiota dysbiosis play a crucial role. Both under- and overnutrition have been shown to be a consequence of food insecurity. The gut microbiota has also been recently implicated in playing a role in under- and overnutrition, with altered community structure and function common to both. The pandemic has already caused significant shifts in food availability which has immediate effects on the gut microbiome. In this opinion paper, we discuss how COVID-19 may indirectly exacerbate the DBM through food insecurity and the gut microbiome. Main text The World Food Programme (WFP) estimates that 265 million people in LMICs will experience acute hunger in 2020 due to the pandemic, nearly doubling the original projection of 135 million. Global border closures to food trade, loss of food production, and stark decline in household income will exacerbate starvation while simultaneously necessitating that families resort to calorie-dense, nutrient-poor foods, thereby increasing obesity. While food insecurity, which is the persistent lack of consistent access to adequate and nutrient-rich foods, will primarily drive nutrition behavior, the gut microbiome is perhaps a key biological mechanism. Numerous human and animal studies describe low diversity and an increase in inflammatory species as characteristic features of the undernourished and overnourished gut microbiota. Indeed, fecal transplant studies show that microbiota transfer from undernourished and overnourished humans to germ-free mice lacking a microbiome transfers the physical and metabolic phenotype, suggesting a causal role for the microbiota in under- and overnutrition. The observed microbiome dysbiosis within severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) coupled with the DBM presents a viscous cycle. Conclusion Low- to mid-income countries will likely see an increase in the DBM epidemic. Providing access to nutritious foods and protecting individuals’ gut microbiome to “flatten the curve” of the DBM trajectory should be prioritized.

The Transition From Undernutrition to Overnutrition Under Adverse Environments and Poverty: The Risk for Chronic Diseases

“…The DBM is defined by WHO as "the coexistence of undernutrition along with overweight, obesity or diet-related non-communicable diseases (NCD), within individuals, households and populations, and across the life-course" and may be aggravated by poor environmental circumstances and genetic predispositions (1). Although a large proportion of deaths among children under five are attributed to malnutrition, overweight and obesity in this age group and older are on the rise (5). The increased risk of NCD related with the nutritional transition in developing countries is a public health concern, due to the potential economic impact and oversaturation of the health system infrastructure (6).…”

“…The dynamic gut microbial ecosystem is directly influenced by the diet and by its bidirectional interaction with the health of the host. In the context of DBM, literature points out that changes in the microbiota can be profoundly influenced by both undernutrition and obesity (5). Long-lasting effects of undernutrition in early life can be attributed to interconnected biological pathways, involving imbalance of the gut microbiome, inflammation, metabolic dysregulation, and impaired insulin signaling (8).…”

“…Among obese adults with similar BMI, those with greater dysbiosis have a higher risk of NCD (27). Some have suggested that changes in the microbiota promoted by SARS-CoV-2 infection associated with dietary changes may exacerbate present and future health risks (5).…”

Nano-biofortification of different crops to immune against COVID-19: A review

“…This disease increases the difficulties and life burdens on the humanity beside the global malnutrition and hidden hunger. It is reported that all forms of malnutrition not might only increase drastically due to the COVID-19 pandemic but the potential of the double burden of malnutrition epidemic, of particular concern, will be also increased ( Littlejohn and Finlay, 2021 ). Therefore, some studies recently published about the production of biofortified crops enriched in some nutrients like Zn, which has the ability to improve the respiratory disorders and pneumonia beside the susceptibility to the outbreak of COVID-19 ( El-Ramady et al, 2021a , Gastélum-Estrada et al, 2021 , Okwuonu et al, 2021 ).…”

Is Nano-Biofortification the Right Approach for Malnutrition in the Era of COVID-19 and Climate change?

“…In 2020, planet Earth faced a huge threats or challenges, including extreme snow disasters, floods and droughts, in Europe, North America, and Asia, unprecedented locust-attacks in Africa, and the global COVID-19 pandemic (Jiang et al 2021). These challenges have had devastating impacts on food security, human health, and the environment (Littlejohn and Finlay, 2021). The human health needs essential nutrients and nutritional compounds and lack of them causes the malnutrition, which means "nutrient deficiency including shortages of vitamins and minerals" (Jiang et al 2021).…”