Magnesium Constraints and Losses Across the Soil – Crop – Food Continuum: Implications for Food Processing, Bioavailability, and Human Health

Magnesium (Mg) inadequacy is an under-recognized nutritional challenge arising from interconnected constraints across the soil–crop–food–health continuum. This review synthesizes evidence on factors that reduce effective Mg supply and on interventions that preserve Mg or improve its bioavailability. Upstream constraints include soil Mg depletion, acidification, cation antagonism, inadequate Mg fertilization, and nutrient dilution in high-yielding cultivars, all of which limit Mg accumulation in edible tissues. Processing further reduces Mg through removal of bran and germ, leaching during cooking, and preservation-related losses. At dietary and physiological stages, refined staples, ultra-processed foods, phytate-rich matrices, and population-specific absorption or excretion risks further constrain effective exposure. Potential solutions include soil diagnosis, balanced Mg fertilization, dolomitic liming, K/Mg management, genotype selection, transporter-informed breeding, reduced milling, parboiling, phytate-reducing fermentation or germination, low-water cooking, and formulation-aware nutrition. The novelty of this review lies in integrating agronomic Mg supply, crop Mg density, processing retention, dietary intake, intestinal absorption, biomarkers, and health outcomes within a single analytical framework. This perspective identifies critical control points and positions Mg inadequacy as a systems-level food-quality and public-health challenge requiring coordinated action across agriculture, food processing, nutrition surveillance, and clinical practice.