What really will it take to introduce universal supplementation programs for all the essential micronutrients? At scale, even at full adult RDA, less than 5 paise per person. A universal supplementation program would ideally be at 50% of RDA, to account for other sources in food and also to eliminate occasional high dosage toxicity.
Here is a table (excludes phosphorus, potassium, iodine and flouride - as deficiencies are rare). Click on the Notion link. The Rainmatter post did not allow a table, so I published it there