The sugar in white milk is naturally occurring and is slightly different depending on the percentage of milk fat. For example, per cup (250 ml) 1-2% milk contains 13 g of sugar (called lactose); 2% -4% contain 12.5 grams of lactose and skim milk contains 11.5 g of lactose. Only flavoured milk has sugar added to it and amount will vary with the formula the processor uses.
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