At Alchimie Forever, we believe phyto-antioxidants are the most powerful way to prevent and repair signs of skin aging. Indeed, antioxidants are not new to beauty and skin care industries and have been on everyone’s lips over the last few years, touted to be the latest “miracle in a jar.” But what exactly are antioxidants? What do they do? How do they work? And which ones should you use?

To understand antioxidants we must understand oxidants

Oxygen, essential to life, is metabolized in the body by successive reductions, leading to superoxide anion (O₂^.–), hydrogen peroxide (H₂O₂), and hydroxyl radical (^.OH) generation. These different molecules are named reactive oxygen species (ROS), or oxidants; some are free radicals (defined by the presence of an unpaired electron), whereas others are non radical (such as H₂O₂, singlet oxygen ¹O₂).

Oxidants, when present in significant quantities, lead to oxidative stress which in turns damages cellular structures.

Exposure of the skin to UV is the main cause of oxidative stress: UV exposure induces the production of high quantities of oxidants, which damage DNA, lipids, membranes, intracellular and extracellular proteins, and sugars. Oxidants have both immediate and long lasting deleterious effects to the skin, including the appearance of actinic keratoses,  a  citrin coloration of the skin (lipid peroxidation), a loss of collagen and elastin (protein alterations), and finally skin cancer (DNA alterations).

Antioxidants: a way to fight oxidants

Antioxidants, as their name indicates, are the opposite of oxidants. What oxidants break, antioxidants can repair.

Endogenous antioxidants

The first key distinction in the family of antioxidants is whether they are endogenous (those produced by the human body) of exogenous (those not produced by the human body). Indeed, human cells are equipped with a series of endogenous antioxidants to deal with the damages caused by oxidants. Such endogenous antioxidants include the following enzymes: superoxide dismutase, catalase, glutathione peroxidase, and thioredoxine reductase. As we age, these endogenous antioxidants are gradually depleted over time; this consumption is accelerated by an increased production of oxidants. Hence the importance of exogenous antioxidants.

Exogenous antioxidants

          Synthetic antioxidants: the case of Idebenone

Idebenone is one of the better known synthetic antioxidants. It is an organic compound of the quinone family and promoted commercially as a synthetic analog of coenzyme Q₁₀ (CoQ₁₀). Idebenone’s antioxidant role involves both the scavenging of oxidants as well as a preventative role in lipid peroxidation. It seems idebenone’s antioxidant properties function by virtue of the electron-donating properties of the hydroquinone form.

Idebenone is present in skin care products from brands such as Prevage (owned by Allergan) and True (which licenses idebenone from Allergan).

          Phytoantioxidants

The alternative to synthetic antioxidants are natural antioxidants, namely those derived from plants. Plants, like human beings, suffer from UV-generated oxidative stress – they live in the sun after all! Plants are, however, unable to protect themselves by moving into the shade or by using sunscreen. Consequently, plants have developed effective antioxidant strategies to protect themselves against the oxidizing stress induced by their environment, in particular UV exposure.

Phytoantioxidants fall into four main groups, namely enzymes, terpens, polyphenols, and vitamins. Some of the best known, and most studied phytoantioxidants are carotenoids (a terpen), and flavonoids and anthocyanins (polyphenols).

Green tea

Green tea contains four major flavonoids: epicatechin, epicatechin-gallate, epigallocatechin, epigallocatechin-3-gallate. These molecules have the ability to scavenge oxidants including O₂^.-, ^.OH, H₂O₂ and ¹O₂. It has been shown that epigallocatechin applied topically with exposure to UVB inhibits the production of H₂O₂ in the dermis and epidermis. Numerous skin care brands use green tea, including Elizabeth Arden and Replenix.

Rosemary

Rosemary contains various antioxidants, in particular phenolic diterpens: carnosol and carnosic acid represent over 90% of the antioxidant properties of rosemary extract. These lipophilic molecules scavenge lipid free radicals, thereby enabling the reduction of lipid peroxidation and inhibiting oxidative damages to skin surface lipids. Carnosic acid also has photoprotective potential. Alchimie Forever and Clarins are two brands that use rosemary in their skin care products.

Grape seeds

Grape seeds are major sources of resveratrol and quercetin. The stilben resveratrol inhibits lipid peroxidation induced by UVB and significantly decreases UVB-induced skin thickness and oedema. The iron chelator flavonoid quercetin maintains and protects the activities of glutathione peroxidase, catalase, and superoxide dismutase after exposure to UV radiation. Caudalie is an example of a skin care brand using grape seeds (and grapes) as its signature ingredient.

Tomato

Tomato is rich in lycopene, a widely studied powerful antioxidant and anti-carcinogenic carotenoid with strong reducing ability and the most effective carotenoid in the scavenging of the oxidant ¹O₂. Lycopene also scavenges lipid radicals, reduces lipid peroxidation and prevents erythema caused by UV radiation on the skin. Kiehl’s and Alchimie Forever both use tomato extract in their products.

Antioxidants represent a key therapeutic approach to preventing skin aging. More specifically, research indicates that the combination of multiple antioxidants at low concentrations represents the most effective approach. Indeed, different antioxidants (whether synthetic or natural) have difference mechanisms of action and target different parts of the cell, thus offering synergies when combined. In the world of antioxidants, 1 + 1 is not 2 but rather 5. As such, the more antioxidant products you use, the better off your skin will be!