nutritional disorders
Overview of Undernutrition
Introduction
Undernutrition is a form of malnutrition. (Malnutrition also includes overnutrition.) Undernutrition can result from inadequate ingestion of nutrients, malabsorption, impaired metabolism, loss of nutrients due to diarrhea, or increased nutritional requirements (as occurs in periods of rapid growth and increased nutritional needs or in disorders [eg, cancer, infection]). Chronic undernutrition occurs when a long-term deficiency in the intake of calories and essential nutrients is insufficient to meet a person's nutritional requirements. Undernutrition progresses in stages; it may develop slowly when it is due to anorexia or very rapidly, as sometimes occurs when it is due to rapidly progressive cancer-related cachexia. First, nutrient levels in blood and tissues change, followed by intracellular changes in biochemical functions and structure. Ultimately, symptoms and signs appear. Diagnosis is by history, physical examination, body composition analysis, and sometimes laboratory tests (eg,albumin). The number of undernourished people in the world has been increasing since 2014. InThe State of Food Security and Nutrition in the World 2023, the United Nations Food and Agriculture Organization (FAO) reported that almost 735 million people, or 9.2% of the global population, were undernourished in 2023, which is 122 million more people than in 2019, before the pandemic. Most live in countries with high rates of food insecurity. The prevalence of undernutrition in Africa rose from 19.4% in 2021 to 19.7% in 2022. In contrast, in Asia, the prevalence of undernutrition decreased from 8.8% in 2021 to 8.5% in 2022, a decrease of more than 12 million people. However, these numbers are 58 million above prepandemic levels. Nearly 600 million people are predicted to be chronically undernourished in 2030. This estimate is 23 million more than it would have been if the war in Ukraine had not occurred and is 119 million more than it would be if neither the pandemic nor the war in Ukraine had occurred. 