# Vitamin D deficiency in South America > Live situation record from CLSTR: https://clstr.news/situations/vitamin-d-deficiency-in-south-america > Updated: 2026-09-12T11:31:49.000Z. Sources: 5. Developments: 2. Vitamin D deficiency has emerged as a significant public health concern across South American populations. In Argentina, estimates suggest the deficiency affects approximately 40% to 45% of the population. Research has explored the nutrient’s role in bone health, immune regulation, and its potential links to cognitive health, though researchers caution that observational studies have not yet established causality regarding dementia risk. In Chile, the situation appears more acute according to National Health Survey data, which indicates that 84% of women of childbearing age exhibit some level of deficiency, and only 13.4% of older adults maintain acceptable levels. This deficiency is attributed to dietary habits and insufficient sunlight exposure. In response, Chilean health policies implemented in June require the fortification of staples such as wheat flour and various forms of milk. Medical specialists emphasize that because the deficiency often progresses asymptomatically, monitoring is essential to prevent issues related to metabolic regulation, mental health, and immune response. ## Timeline ### 2026-09-12: Vitamin D deficiency impacts Chilean population Chile faces widespread Vitamin D deficiency, prompting new food fortification policies. Experts highlight the nutrient's critical role in immune, metabolic, and mental health. 3 sources. https://clstr.news/cluster/vitamin-d-deficiency-impacts-chilean-population ### 2026-08-25: Vitamin D deficiency affects nearly half of Argentina's population Vitamin D deficiency affects nearly half of the Argentine population. While studies explore its link to cognitive health, experts caution against assuming causality regarding memory improvement. 2 sources. https://clstr.news/cluster/vitamin-d-deficiency-affects-nearly-half-of-argentinas-population --- Cite as: Vitamin D deficiency in South America. CLSTR, https://clstr.news/situations/vitamin-d-deficiency-in-south-america