310 Lemonade is sugar-free, so why is there oligofructose and fructose included in the ingredients?

The FDA defines “sugar free” in Title 21 of the Code of Federal Regulations (21 CFR 101.60 (c)) as less than 0.5g of sugars per labeled serving. A serving of 310 Lemonade contains roughly 100mg (0.1g) of sugar/fructose (from natural sugar beet), well below the required FDA level, making it sugar-free by their standards.

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