That just a list of the nutritional values of the milk. That's not a list of ingredients. The sodium was not added; it naturally occurs in cow milk.
Calories, Fat & Carbohydrates in
Milk: Cow, Fat-Free, Skim
Average All Brands
Serving Size: 8.6 oz.
Nutrition Facts
Calories 91
(Kilojoules 379)
% DV**
Total Fat 0.6 g 1%
Sat. Fat 0.4 g 2%
Cholesterol 5 mg 2%
Sodium 130 mg 5%
Total Carbs. 12.3 g 4%
Dietary Fiber 0 g 0%
Sugars 12.3 g
Protein 8.7 g
Calcium 316.1 mg
Potassium 419 mg
CalorieKing - Calorie Counter - Calories in Milk: Cow, Fat-Free, Skim