Addressing the root causes: leveraging nutrition to accelerate the end of TB

As we observe the rising incidence of TB in marginalized communities, it becomes crucial to question why this malice persists in an evolving society. Historically TB was the leading cause of death among the various infectious diseases prevalent in the 19th century in high-income countries. There was a dramatic decline in TB incidence and mortality even before effective TB medicines were introduced in the 1950s, mainly due to better living conditions, public health measures and nutrition.1Cegielski J.P. McMurray D.N. The relationship between malnutrition and tuberculosis: evidence from studies in humans and experimental animals.Int J Tuberc Lung Dis. 2004; 8: 286-298PubMed Google Scholar However, TB remains a major infectious disease killer in low- and middle-income countries today, and it disproportionately affects poor people living in high-income countries as well. Undernutrition is one of the main risk factors for progression from TB infection to disease and poor treatment outcomes.2Lönnroth K. Jaramillo E. Williams B.G. Dye C. Raviglione M. Drivers of tuberculosis epidemics: the role of risk factors and social determinants.Soc Sci Med. 2009; 68: 2240-2246Crossref PubMed Scopus (724) Google Scholar In 2022, about 2.2 million (20%) of incident TB cases were attributable to undernutrition, while about 0.9 million (9%) were attributable to HIV.3Global Tuberculosis Report 2023 Geneva: World Health Organization.https://www.who.int/teams/global-tuberculosis-programme/tb-reports/global-tuberculosis-report-2023Google Scholar Underweight individuals (BMI <18.5 kg/m2) could be up to five times more likely to develop TB compared to individuals within a normal weight range (BMI 18.5–24.9 kg/m2).1Cegielski J.P. McMurray D.N. The relationship between malnutrition and tuberculosis: evidence from studies in humans and experimental animals.Int J Tuberc Lung Dis. 2004; 8: 286-298PubMed Google Scholar,4Bhargava A. Bhargava M. Beneditti A. Kurpad A. Attributable is preventable: corrected and revised estimates of population attributable fraction of TB related to undernutrition in 30 high TB burden countries.J Clin Tuberc Other Mycobact Dis. 2022; 27100309https://pubmed.ncbi.nlm.nih.gov/35308808/PubMed Google Scholar People with undernutrition lack critical macro- and micro-nutrients that modulate the immune system and protect them from developing the disease.5Dauphinais M.R. Koura K.G. Narasimhan P.B. et al.Nutritionally acquired immunodeficiency must be addressed with the same urgency as HIV to end tuberculosis.BMC Global Public Health. 2024; 2: 4Crossref Google Scholar, 6Gombart A.F. Pierre A. Maggini S. A review of micronutrients and the immune system–working in harmony to reduce the risk of infection.Nutrients. 2020; 12: 236Crossref PubMed Scopus (708) Google Scholar, 7Munteanu C. Schwartz B. The relationship between nutrition and the immune system.Front Nutr. 2022; 91082500https://doi.org/10.3389/fnut.2022.1082500Crossref PubMed Scopus (41) Google Scholar Young children and pregnant women are particularly vulnerable to the effects of undernutrition and TB. TB patients who miss most of their meals are unlikely to visit health facilities and may lack motivation to take their daily medicines for months. Nutritional supplements had been used widely to prevent TB until the introduction of multi-drug treatment in the 1960s, when global attention shifted towards biomedical treatment and away from nutrition. The data from recent studies clearly indicate that nutrition plays a significant role in fighting against TB. For instance, studies like the RATIONS Trial and the current modelling paper by Mandal et al. have highlighted the positive impact of proper nutrition on TB prevention and treatment outcome.8Bhargava A. Bhargava M. Meher A. et al.Nutritional supplementation to prevent tuberculosis incidence in household contacts of patients with pulmonary tuberculosis in India (RATIONS): a field-based open-label, cluster-randomised, controlled trial.Lancet. 2023; 402: 627-640https://doi.org/10.1016/S0140-6736(23)01231-XSummary Full Text Full Text PDF PubMed Scopus (29) Google Scholar,9Mandal S. Bhatia V. Bhargava A. Rijal S. Arinaminpathy N. The potential impact on tuberculosis of interventions to reduce undernutrition in the WHO South-East Asian Region: a modelling analysis.Lancet Reg Health Southeast Asia. 2024; https://doi.org/10.1016/j.lansea.2024.100423Summary Full Text Full Text PDF Scopus (0) Google Scholar Nutritional supplementation will be particularly important, as factors such as the COVID-19 pandemic, climate change, and conflict further threaten food security.10Carwile M.E. Hochberg N.S. Sinha P. Undernutrition is feeding the tuberculosis pandemic: a perspective.J Clin Tuberc Other Mycobact Dis. 2022; 27100311PubMed Google Scholar Several studies have shown that providing nutritional support to TB patients and those at risk can significantly reduce TB incidence and improve treatment outcomes by strengthening the immune system and enhancing overall health.7Munteanu C. Schwartz B. The relationship between nutrition and the immune system.Front Nutr. 2022; 91082500https://doi.org/10.3389/fnut.2022.1082500Crossref PubMed Scopus (41) Google Scholar,11Du Y. He Y. Zhang H. et al.Declining incidence rate of tuberculosis among close contacts in five years post-exposure: a systematic review and meta-analysis.BMC Infect Dis. 2023; 23: 373Crossref PubMed Scopus (1) Google Scholar Policymakers and health care providers must prioritize nutritional interventions alongside the scale-up and use of new and existing tools to achieve the WHO End TB Strategy targets. While nutritional supplementation has been a commendable effort and should be continued, it is essential to recognize that it alone cannot address the root causes of TB. Micronutrient supplementation to TB patients and vulnerable populations provide short-term relief, but they do not tackle the systemic issues. TB is not merely a medical challenge; it is a social scourge perpetuated by economic disparities. While nutritional deficiency is one of the key drivers of TB, it is also an important symptom of the deeper issue of poverty and inequality, which exert an even more profound influence on TB. Poverty remains the main driving factor for sustained TB burden and addressing poverty is crucial in the fight against TB and should therefore receive much more concerted attention.12Saunders M.J. Evans C.A. Fighting poverty to prevent tuberculosis.Lancet Infect Dis. 2016; 16: 395-396Summary Full Text Full Text PDF PubMed Google Scholar Through studies such as the food RATIONS trial in India, we are starting to understand what works: there is an urgent need to scale up these interventions at the country level, while also generating similar evidence for other dimensions of poverty, and likewise translating this evidence rapidly into public health action.8Bhargava A. Bhargava M. Meher A. et al.Nutritional supplementation to prevent tuberculosis incidence in household contacts of patients with pulmonary tuberculosis in India (RATIONS): a field-based open-label, cluster-randomised, controlled trial.Lancet. 2023; 402: 627-640https://doi.org/10.1016/S0140-6736(23)01231-XSummary Full Text Full Text PDF PubMed Scopus (29) Google Scholar,9Mandal S. Bhatia V. Bhargava A. Rijal S. Arinaminpathy N. The potential impact on tuberculosis of interventions to reduce undernutrition in the WHO South-East Asian Region: a modelling analysis.Lancet Reg Health Southeast Asia. 2024; https://doi.org/10.1016/j.lansea.2024.100423Summary Full Text Full Text PDF Scopus (0) Google Scholar,12Saunders M.J. Evans C.A. Fighting poverty to prevent tuberculosis.Lancet Infect Dis. 2016; 16: 395-396Summary Full Text Full Text PDF PubMed Google Scholar It is time to shift our focus. Poverty alleviation and eliminating inequalities and hunger (part of the Sustainable Development Goals) require multi-sectoral collaborations, concerted efforts, and renewed commitments from local and international communities.13United NationsSustainable development goals.https://www.un.org/sustainabledevelopment/sustainable-development-goalsGoogle Scholar Let us recognize poverty and hunger as the true adversaries in the fight against TB and work collectively to eradicate them. Only then can we truly combat TB. We must engage in an open dialogue and explore innovative and sustainable solutions. Our efforts should extend beyond nutritional supplements and delve into systemic changes that empower communities and ensure access to nutritious food. TB is just one consequence of poverty, but an important one: achieving progress towards the End TB goals will be a powerful indication of success in alleviating poverty and hunger. MAY—conceptualization and preparation of the first draft. AB—critical inputs and revising of the drafts. MAY and AB—finalization and approval of the manuscript. Both authors declare no conflict of interest. Dr Mohammed A. Yassin is the Senior TB Advisor, the Global Fund to fight AIDS, Tuberculosis and Malaria, Geneva, Switzerland and Dr Arvind Betigeri is the Regional Food Fortification Advisor, UN World Food Programme, Regional Bureau for Asia and the Pacific, Bangkok, Thailand. The views and recommendations expressed in the Commentary are the authors’ only. The potential impact on tuberculosis of interventions to reduce undernutrition in the WHO South-East Asian Region: a modelling analysisNutritional interventions could cause substantial reductions in TB burden in the Region. Their health benefits extend well beyond TB, underlining their importance for public health. Full-Text PDF Open Access