Our skin is constantly exposed to oxidative stress from UV radiation, environmental pollution, and endogenous metabolic processes. Free radicals, highly reactive oxygen molecules that attack cells and tissues, can damage cell structures, destabilize the extracellular matrix, and promote premature skin aging. At the same time, from young adulthood onward, the quality and quantity of the skin's own lipids decrease—a key factor for barrier function, suppleness, and protection. The O4 Skin Renewal Overnight Mask therefore combines lipophilic antioxidants with nourishing lipid components to mitigate oxidative processes and regenerate the skin structure.

Coenzyme Q10 (ubiquinone) is a naturally occurring antioxidant with a central role in mitochondrial energy production in cells. It neutralizes reactive oxygen species (ROS) in the lipid phase, protects cell membranes and DNA from oxidative damage, and promotes the energy production of ATP in skin cells.

Lipochroman™ (Dimethylmethoxy Chromanol) is a synthetic antioxidant with a particularly broad spectrum of activity against ROS (reactive oxygen species) and RNS (reactive nitrogen species). It neutralizes both oxygen- and nitrogen-based radicals, inhibits lipid peroxidation in cell membranes, and stimulates antioxidant enzymes, such as glutathione peroxidase.

Vitamin E, or tocopherol, is a physiological, fat-soluble antioxidant with a high affinity for cell membranes and the skin's lipid structures. It neutralizes free radicals, especially reactive oxygen species, which can attack cell structures, thereby interrupting the chain reaction of oxidative lipid peroxidation. This is a key process in skin aging. Tocopherol particularly protects the polyunsaturated fatty acids in the cell membrane and contributes to the stability and functionality of the skin's lipid layer. It also supports the regeneration of other antioxidant systems, such as coenzyme Q10, and works in conjunction with other lipophilic free radical scavengers. This protective effect strengthens the skin's resistance to environmental stressors.

Shea butter (Butyrospermum Parkii butter) is a plant-based lipid source extracted from the kernels of the West African shea tree. The butter is characterized by its high content of unsaponifiable, and therefore chemically stable, components: phytosterols, tocopherols, and essential fatty acids such as oleic and stearic acid. These ingredients support the physiological structure of the skin's lipid barrier and promote the restoration of the skin's natural protective layer. Shea butter forms a gentle, breathable protective film on the skin (non-occlusive), reducing moisture evaporation. In vitro and in vivo data demonstrate that shea butter improves skin elasticity, reduces transepidermal water loss (TEWL), and soothes the skin, particularly dry, irritated, or sensitive skin. After weeks of regular use in studies, skin hydration, smoothness, and overall skin feel noticeably improve.

Jojoba oil is a skin-compatible, plant-based wax oil that stabilizes and nourishes the natural lipid barrier. Unlike traditional plant oils, it does not consist of triglycerides but is chemically a liquid wax, an ester of long-chain fatty acids and fatty alcohols. Due to this unique structure, it is particularly resistant to oxidation, does not become rancid, and remains effective for a long time.

The similarity to human sebum makes jojoba oil particularly well-tolerated, non-comedogenic (does not cause breakouts), and ideal for supporting natural sebum regulation. It absorbs well, leaves the skin feeling smooth, and forms a breathable lipid film that protects the skin from transepidermal water loss without clogging pores.