Fructose found in fruit and refined sugar have the same effect on cell metabolism.

Caveats

• The claim conflates molecular pathway identity with metabolic equivalence — the intracellular enzymatic steps for fructose are the same regardless of source, but the dose, rate, and magnitude of fructose reaching cells differ dramatically between whole fruit and refined sugar, producing different metabolic outcomes.
• Metabolic harms from fructose (fatty liver, insulin resistance, ATP depletion) are dose-dependent; dietary fiber in whole fruit can redirect fructose metabolism toward gut bacteria rather than the liver, fundamentally changing cellular exposure.
• The proponent's argument relies on a reductionist fallacy — isolating the biochemical pathway while ignoring that delivery context (food matrix, fiber, co-nutrients) is inseparable from actual cellular metabolic effects.