Antioxidants are a key aspect to skin health and longevity. It’s one of the most popular terms you’ll hear in the beauty industry, and it’s warranted given the critical role they play.

Let’s discuss what makes something an antioxidant, how they work and how they benefit our skin. Antioxidant (molecular) stability depends on things like bond strength and charge which you’ll see below has quite the impact on things. I’ve included a terminology section to help better understand this topic and the information discussed.

Terminology
·      Atom: the simplest form of an element, an individual element on the periodic table

o   Example: Hydrogen (H), Oxygen (O), Aluminum (Al), Iron (Fe)

·      Molecule: a collection of elements bonded together

o   Example: Water (H₂O), Carbon Dioxide (CO₂), Ammonia (NH₃)

·      Proton (H⁺): a subatomic particle (smaller than an atom) with a positive charge

·      Electron (e^-): a subatomic particle (smaller than an atom) with a negative charge

·      Charge: stems from the amount of each subatomic particle and gives rise to a (partial) positive or (partial) negative charge on the atom or molecule

o   Example: Sodium (Na⁺), Chlorine (Cl^-), Ammonium (NH₄⁺)

·      Oxidation: a chemical reaction where there is a loss of an electron by a reactant (molecule, atom, ion)

o  Example: A – e^-  ➡ A⁺

·      Reduction: a chemical reaction where there is a gain of an electron by a reactant (molecule, atom, ion)

o  Example: B + e^-  ➡ B^-

·      Free radical: atoms or molecules with an unpaired electron creating an imbalance and a highly reactive atom/molecule

o   Example: Superoxide radical (O₂^{• -}), Hydroxyl radical (•OH)

Antioxidants
An antioxidant is a compound that helps negate oxidation. Oxidation is a chemical reaction that can produce free radicals. The chemical structure of the antioxidant warrants this important behavior. Antioxidants have the ability to donate electrons or hydrogen atoms (one proton and one electron) which changes the environment of the atoms within the antioxidant and whatever it donates to. Not all molecules have the ability or desire to do this (not all molecules are antioxidants). Often, most molecules are happy and content being balanced. While this behavior is valuable, it does lead to stability issues within antioxidants. Things like packaging and storage conditions become very important to maintain the lifetime and efficacy of the antioxidant or product. To assist with the longevity of antioxidants, it’s best to limit exposure to light, oxygen and heat as all of these can degrade them. There are numerous antioxidants available but, in terms of skincare, there is limited data on most of them. This sparsity means that the mechanistic behavior of most antioxidants has not been proven or demonstrated and thus we don’t truly know if (and how) they provide any benefit the skin.

Free radicals
Free radicals are molecules that have a missing electron which make them ultra-reactive. This lack of balance means that they are desperate to find another electron to form their natural pair with. They will bond with or take an electron from anything they can. They aren’t picky, whatever they come across first that allows them to reestablish equilibrium they will attack. What this means is that they can take an electron from another happy, balanced molecule which will cause that molecule to be under oxidative stress.

The relationship between antioxidants and free radicals
So what does this all mean in terms of skin health? Free radicals are damaging to the components within our skin cells. They have shown to damage our DNA as well as the mitochondria which is important for cell energy and the liveliness of cells and thus our skin. Damage to the cell like this will ultimately lead to cell mutations and death. What this translates to visually is a damaged skin barrier, premature wrinkles, hyperpigmentation, accelerated loss of collagen and elastin and uneven skin tone. Luckly, antioxidants can help mitigate free radical damage by quenching them. The antioxidant sacrifices itself to donate an electron to the free radical. This neutralizes the free radical and eliminates its ability to go on and be destructive throughout the body. The catch is, when an antioxidant molecule provides that donation its chemical structure changes, meaning it’s no longer the antioxidant it was before the donation. Furthermore, this means that while antioxidants protect our skincare products and our skin, we may not be able to receive the other benefits they offer because of this structural change. It has been debated that when antioxidants are included in a formula, they end up serving as more of a preservative by protecting the formula versus offering topical skin benefits.

Regardless, antioxidants are incredibly important for protecting our skin from all the stressors we are introduced to throughout the day. Ascorbic acid is one of the most well researched ingredients and deserves a spot in your skincare routine.