Progress in malnutrition diagnosis: assessing conventional techniques and the growing significance of laser spectroscopy in nutrient analysis

Malnutrition remains a pressing global health challenge, particularly in low- and middle-income countries, where inadequate nutrient intake leads to severe health complications. Accurate and timely diagnosis is essential for effective intervention, yet traditional methods such as anthropometric assessments and clinical evaluations lack the specificity needed to quantify individual nutrient levels. Conventional laboratory techniques, including chemical assays and chromatography, provide detailed nutrient analysis but have significant limitations. Many of these techniques are bulky, expensive, non-portable, and require extensive sample preparation, making them impractical for on-site or resource-limited settings. The need for a rapid, cost-effective, and portable diagnostic tool that can assess multiple nutrients simultaneously has become increasingly evident. This review explores laser-based spectroscopic techniques as a potential solution for precise and efficient nutrient analysis. Spectroscopy enables rapid, non-invasive biochemical profiling of biological samples with minimal preparation. Various laser spectroscopic methods, such as Laser-Induced Breakdown Spectroscopy (LIBS), Raman Spectroscopy, and Laser-Induced Fluorescence (LIF), have demonstrated their capabilities in detecting specific macro and micronutrients. LIBS is particularly effective for elemental analysis of minerals, Raman provides molecular fingerprinting of organic compounds, and LIF enhances detection through fluorescence-based biomolecule identification. The review highlights how integrating these techniques into a multi-modal spectroscopic system can provide complementary information, enabling a comprehensive and portable diagnostic tool for malnutrition assessment. This unified approach holds promise for on-site applications, particularly in resource-constrained environments, where access to conventional laboratory facilities is limited.