Keratins are a group of tough, fibrous proteins that help maintain healthy joints and support skin, hair and nails. Keratins deliver an exceptionally high content of the amino acid cysteine, which is in itself an abundant source of sulfur molecules that nourish and strengthen cartilage tissues. When the sulfur molecules from cysteine bond together they form very strong links called "cysteine bridges." These bridges provide vital support for weight-bearing joints. New Swanson Premium Brand® Keratin, derived from Tibetan wool, supplies pure, food-grade hydrolyzed keratin to nourish healthy connective tissues and promote the health, strength and appearance of skin, hair and nails.

Aging is associated with the loss of elasticity of skin and with deteriorating connective tissue health. The amount of the two main components of connective tissue (collagen and keratin) declines with age and scientific research has shown that supplementing with keratin can slow the worsening of skin, nail, and hair quality due to age or conditions characterized with high amounts of oxidative stress. Keratin has been shown to increase the levels of anti-oxidant enzymes in connective tissue cells. Keratin also stimulates skin cells to proliferate more rapidly, which means there are more cells to produce structural proteins and thus increase connective tissue health.

A combination of essential vitamins and keratin has been shown in a clinical trial to decrease the number of hairs lost due to washing of the hair of women taking the supplement, to increase hair strength and to promote hair growth which leads to shinier and better quality hair. Nail quality is also influenced by keratin supplements compared to placebo – the tendency of nails to break has been improved as well as their hardness, resistance to bending and breaking, overall integrity, smoothness and natural appearance. Additionally, skin health is also maintained and improved when women aged 40 to 71 years take keratin supplements - improved skin moisture, reduced wrinkle depth, better skin elasticity and smoothness, and decreased skin roughness are the result.

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