Adding nutrients such as vitamins and minerals to processed foods like cereals, to make good losses from processes such as milling. Fortification, by contrast, means adding nutrients to foods to remedy dietary deficiencies in particular population groups. Restoration replaces nutrients lost in milling — iron, thiamine, niacin — returning the food to its natural level, while fortification adds nutrients beyond natural levels to address deficiencies, e.g. vitamin D in milk or iodine in salt. Programmes are designed from dietary surveys, with overage allowances for processing and storage losses.