GREEN, BLACK, AND WHITE TEAThe harvested leaves of Camellia are steamed in the production of green tea and are then spread under the sun, pressed, and dried. Steaming the leaves prevents fermentation, the process that produces black tea. Steaming also prevents the polyphenols from oxidizing and preserves the chlorophyll that gives green tea its beautiful color. Polyphenols and methylxanthines are the primary constituents of green tea’s chemical composition. Polyphenols are the most abundant compounds in green tea leaves, with the most important being flavonols (catechins). The catechin that is commonly used in skin care is epigallocatechin. The primary substance in methylxanthine is caffeine.
Matcha is obtained from Camellia sinensis that is shade-grown. It is then stone-ground or pulverized into a fine powder, preserving the whole leaf. Its polyphenols, mainly epigallocatechin gallate, are responsible for the anti-inflammatory, antioxidant, antimetalloproteinase and photoprotective properties of green tea and play an important role in products targeted at almost all skin conditions and skin types. Matcha makes a wonderful mask.
Black tea is made of fully fermented (enzymatically oxidized) leaves and its catechins are oxidized during the manufacturing process, forming theaflavins, another group of polyphenols that are also potent antioxidants. While black tea, as well as oolong, is very low in catechins, it is rich in theaflavins. Some studies demonstrate that the theaflavins existent in black tea have similar antioxidant potency as the catechins present in green tea.
White tea is made of leaves harvested at a much earlier growth phase, sometimes buds, and is promptly steamed to inactivate the catechin-destroying enzyme, polyphenol oxidase. Consequently, white tea is richer in catechins than green tea. In some studies, white tea has shown the greatest level of activity per milligram of extract as an inhibitor of matrixmetalloproteinases, collagenase, and elastase and as an antioxidant.
ACNEEpigallocatechin gallate, the major polyphenol in green tea, reduces sebum, inflammation, and viability of P.acnes. It reduces inflammation by reducing leukocyte diffusion and suppressing nuclear factor kappa beta and activator protein-1 pathways and reduces sebum by modulating various signaling pathways. It also causes apotosis of SEB-1 sebocytes and decreases lipid peroxidation. Epigallocatechin gallate addresses all of the pathogenic characteristics of acne. Methylxanthines have lipolytic properties that make them beneficial in treating acneic conditions, especially when excessive sebum is present.
YOUTHFUL SKINThe major benefit of green tea in anti-aging skin care lies in its inhibitory effects on collagenase from the polyphenols. Polyphenols inhibit metalloproteinases, specifically collagenase, and elastase, the enzyme responsible for the breakdown of structural components in the skin’s matrix. Aging skin is greatly attributed to functional changes of protein fibers and vascular endothelium, which is why microcirculation is so important.
SUN PROTECTIONGreen tea exerts photoprotective actions by reducing erythema formation and inhibiting UVB-induced infiltration of macrophages into the epidermis. Additionally, it inhibits interleukin-1 proliferation, which plays a role in abnormal cell, such as skin cancer, proliferation.
ANTI-CELLULITEMethylxanthines stimulate microcirculation and promote vasodilation response. In addition to stimulating blood flow, methylxanthines are lypolitic and anti-lipogenic, making them an excellent addition in body care products, specifically those targeted at cellulite and control of adipose tissues. Furthermore, there is a synergistic action between caffeine and catechin polyphenols in green tea that enhances the stimulatory effect.
GREEN TEA SEED OILCamellia oil, also called tea oil, can come from Camellia sinensis or Camellia oleifera. Camellia oleifera produces beautiful flowers at the end of winter that contain oily seeds. Camellia oleifera is a shrub of the tea family and is mainly grown in the southern provinces of China. It is cultivated specifically for its seeds, as opposed to Camellia sinensis, which is cultivated mostly for its leaves.
Camellia japonica oil is known as Japanese tea oil and tsubaki oil. It is a flowering plant with red blooms, but it does not produce tea leaves. This oil is frequently used in cosmetic applications.
Camellia oil has qualities similar to those of olive oil and is highly regarded by skin care formulators for its excellent oxidative stability, light texture, and fast absorption. The omega-6 fatty acids of the oil provide its highly emollient and rejuvenating qualities. The extraction method, such as cold pressing, supercritical carbon dioxide, solvent, or Soxhlet, and the extraction time, influences its fatty acid profile. Generally speaking, Camellia oil is high in oleic acid, making it best suited for dry skin types. It is a pretty amber green color with a sweet and pleasant aroma, making Camellia seed oil a great carrier oil for aromatherapy.
In sourcing products with Camellia, look for those with certifications, including Ecocert, Cosmos, Natrue, or BioSuisse to ensure the product is pure, toxin-free, and of standardized potency.
Krista McKowen, a licensed aesthetician and instructor with a passion for wellness, has over 34 years of experience in the skin care industry, ranging from spa owner and medical spa director to writer and educator. Through a dedication and philosophy of creating beauty through skin health, McKowen has both a clinical and holistic background. Her expert knowledge stems from extensive and ongoing studies in cosmetic chemistry, massage therapy, aromatherapy, thallasotherapy, phytotherapy, health, and nutrition.