Reduces D-xylose into xylitol. Has a preference for NADPH, but can also utilize NADH as cosubstrate (By similarity). NAD(+) + xylitol = D-xylose + H(+) + NADH NADP(+) + xylitol = D-xylose + H(+) + NADPH Carbohydrate metabolism; D-xylose degradation. Belongs to the aldo/keto reductase family.