Vitamin C is water-soluble and gets stuck outside fat-rich tissue. Vitamin E is fat-soluble and barely moves through water-based fluids. Glutathione, the body's "master antioxidant," gets broken down in your stomach before it reaches your bloodstream.
Molecular hydrogen (H₂) is two hydrogen atoms bonded together. The smallest molecule in existence. Smaller than water. Smaller than oxygen. Small enough to pass through every membrane in your body — cell walls, mitochondria, even the blood-brain barrier.
Other antioxidants knock on the door. Hydrogen walks in.