For Chen Yu and Hiromi Jounouchi, both Demigods, every mouthful of this soup can boost their power if not sealed and absorbed slowly.
Yet, the rapid power growth can lead to a loss of control, causing their power to leak and reveal their Demigod forms.
As for Chen Yu's parents and Little Yixi, it's merely a nourishing seafood soup. The true essence has settled into their bodies, not showing any divine manifestation at the moment, but the effects will reveal over time.
Simply put, Chen Yu's parents will grow increasingly youthful and healthier, their lifespan greatly extended, their bodies transforming at the cellular level to the point where they won't age anymore.
Moreover, the divine essence nourishes their souls, complementing their ageless bodies, making their lifespans comparable to the Long-Lived Kind.