In this article, we will explore the medical applications of Molecular Hydrogen (H₂). It is important to note that Molecular Hydrogen, along with Oxygen (O₂) and Ozone (O₃), belongs to a category of molecules that are either diatomic or triatomic and composed of atoms of the same element. While these molecules share this fundamental characteristic, they exhibit distinct chemical properties and biological roles. These differences are primarily due to the unique nature of the constituent atoms and the specific molecular structures they form.
Hydrogen is the most abundant chemical element in the universe, constituting approximately 75% of visible matter. For example, the Sun of our Solar System contains 71% Hydrogen, which, through fusion, produces helium-4 and thereby releases immense energy.
Hydrogen is also the smallest existing molecule and, being neutral and nonpolar, has high bioavailability (the ability of a substance to be absorbed and used by the body). It can easily penetrate any space in the body’s membranes. Moreover, Hydrogen does not dissociate into its electrons and protons when dissolved in water, thus not altering the pH.
Gaseous Hydrogen possesses potent and selective antioxidant effects. It primarily functions by improving the redox state of the cell when necessary. It is clinically proven that Hydrogen benefits all organs of the body by extremely effectively reducing oxidative stress and inflammation.
To date, there are thousands of publications on the therapeutic effects of Hydrogen, demonstrating its efficacy on more than 170 different disease models in humans and animals. Various methods for administering Hydrogen exist, including inhaling Hydrogen gas, drinking and/or bathing in hydrogenated water, intravenous injections of Hydrogen-rich saline solutions, and Hyperbaric Hydrogen therapy.
Despite being known for more than two centuries and being used in numerous industrial processes, medical applications of Hydrogen are relatively new. A pioneering article was published in 2007 in the journal Nature Medicine, demonstrating that Hydrogen gas was effective in preventing brain damage caused by artificially induced ischemic reperfusion, through occlusion of the middle cerebral artery in lab rats. This demonstrated that Hydrogen can act as a therapeutic antioxidant by selectively reducing cytotoxic oxygen radicals, especially hydroxyl radicals and, to a lesser extent, peroxynitrite, without diminishing other oxidants like Hydrogen peroxide or superoxide.
Despite such promising results, most research on the therapeutic effects of Hydrogen has been conducted in Asian countries. Molecular Hydrogen compensates for oxidative stress, which is one of the most crucial mechanisms harming human health. For this reason, Hydrogen is extraordinary; it has such unique antioxidant effects that specifically address the most damaging free radicals.
When free radicals reach excessively high levels, such as superoxide, peroxynitrites, or ionizing radiation, they can become hydroxyl radicals, which are damaging due to their high reactivity. However, other free radicals like nitric oxide (an essential free radical that causes vasodilation) are beneficial. There are superoxide radicals and other oxidants like Hydrogen peroxide that are crucial for health if found in correct concentrations and locations.
Cells require both oxidation and a reduction in oxidation for everything to function properly. When that balance is disrupted by excessive oxidation, oxidative stress occurs. And if insufficient oxidation is present, other serious problems may develop. In many cases, the damage is not caused by an excess of free radicals but rather by a dysregulation of the redox state (a chemical reaction in which one or more electrons are transferred between reactants, causing a change in their oxidation states).
While Hydrogen acts selectively, meaning it only reduces toxic radicals like the hydroxyl radical, most other antioxidants are not selective, and this can pose a problem. We need free radicals, and different studies have shown that one can suffer from both excessive oxidative stress and excessive reductive stress (or not having enough oxidative potential), not only in the same body or the same organ but even in the same cell. With too much oxidative stress in the cytosol, one cannot generate enough oxidative power in the endoplasmic reticulum.
Hydrogen helps to reverse everything back to homeostasis (a state of equilibrium among all the body’s systems needed for the body to function correctly) since although Hydrogen has antioxidant effects, its main action is improving the cells’ redox state. As a result, it produces numerous improvements, for example in the levels of superoxide dismutase and glutathione.
Hydrogen not only selectively reduces the most toxic radicals but can also help prevent an excess (which becomes toxic) of free radicals from occurring in the first place. This is a potent preventive mechanism.
Another mode of action occurs by activating the Nrf2 pathway (a protein that controls how certain genes are expressed) when needed. Nrf2 is a transcription factor that, when activated, enters the cell nucleus and binds to the antioxidant response element in the DNA. It then induces the transcription of other cytoprotective enzymes like glutathione, superoxide dismutase, catalase, glutathione peroxidase, phase II enzymes, heme oxygenase 1, and many others.
A study analyzing metabolic syndrome found that participants who drank Hydrogen-enriched water experienced a 39% increase in extracellular superoxide dismutase. Therefore, it can be stated that Hydrogen has this antioxidant effect as it can help regulate the Nrf2 pathway and return cytoprotective enzymes and proteins to the levels they are supposed to be; back to the realm of homeostasis.
Cyclical consumption of Hydrogen helps to maintain the body’s cellular redox state in balance. Intermittent use of Hydrogen, for example, drinking hydrogenized water several times a day, is a more optimal strategy than using it continuously. This cyclical process prevents the homeostasis from becoming stagnant.
In conclusion, Hydrogen has immense therapeutic potential as an antioxidant and redox regulator. It functions through multiple mechanisms to modulate the cellular redox state, thereby impacting a multitude of physiological processes positively. Its safe, non-toxic nature and selective action make it an ideal candidate for preventive and therapeutic applications in a myriad of health conditions. While research on its extensive applications is still burgeoning, the evidence thus far is promising and warrants further investigation.