Life Extension Magazine®

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Beauty from Within: Healthy Hair, Skin, and Nails

Wrinkled skin, brittle nails, and dry hair indicate a decline in our internal structural proteins. Replenishing these proteins through bioavailable keratin, collagen, and other micronutrients can revitalize skin, hair, and nails from the inside out.

Scientifically reviewed by: Julia Dosik, MPH, in August 2023. Written by: Marcus Phillips.

People today go to extreme lengths to cover up tired, dull, lifeless skin, nails, and hair.

What few understand is that outward appearances of skin wrinkles, brittle nails, and dry hair are more than superficial cosmetic issues. They are indicators of the aging of connective tissue throughout our body.1-3

Connective tissue provides support to hair, skin, and nails. As we mature, a decline in the production of structural proteins causes deterioration of the body’s connective tissues.

Fortunately, many of these surface changes can be thwarted using an ingestible combination of bioavailable keratin and collagen.

Clinical studies document reversals in markers of superficial aging in response to replenishing the body’s structural proteins.

These improvements are reflected through more lustrous hair, stronger nails, and vibrant skin.

Why Cosmetics Fail

As we age, our bodies produce less keratin and collagen, two key structural proteins that are essential to the health of the tissues that comprise hair, skin, and nails.

On the outside of our body, this breakdown results in hair loss, dry and wrinkled skin, and dull, brittle nails.

However, these “cosmetic” changes are reflective of more serious problems on the inside, including changes in blood vessel walls, bone, connective tissues, and other vital organs where these essential structural proteins are predominant.

The Keratin Connection

The Keratin Connection 

For many who have cosmetic problems that occur due to the decline in the body’s keratin supply, the logical solution is to replace the essential keratin in the body.

The problem with many commercial keratin preparations is that they are made from hooves, horns, and feathers. As a result, they lack biological activity in humans because they have been over processed during exposure to heat and other harsh conditions.4

Scientists have developed a patented process that makes keratin soluble, preserves its bioactivity, and makes it digestible. Solubilized keratin contains highly bioavailable protein-forming building blocks, including sulfur-containing amino acids, to replace the keratin that is lost in the aging process.4,5

The result is the delivery of high-quality keratin proteins directly to the cells that help form hair, nails, and skin.4 Solubilized keratin has a high bioavailability, meaning that it can rapidly start replenishing depleted keratin.6

Laboratory studies have shown that soluble keratin stimulates skin cells to proliferate at a rate up to 160% greater than they would without the protein, permitting cells to then increase their own production of structural proteins.4 This results in an increase in the thickness of the epidermis, which translates to a reduction in fine lines and depth of wrinkles. Furthermore, promotion of healthy skin cells also reduces water loss by improving the skin’s barrier function and providing firmness and elasticity.4,7

Chronic oxidative stress and ultraviolet light exposure can lead to a decline in skin vitality.8 In preclinical research, supplementation with this new keratin has shown to rebuild the natural enzyme systems in cells, including glutathione and superoxide dismutase.4

What You Need to Know
Beauty from Within

Beauty from Within

  • Deteriorating hair, nails, and skin appearance is not only unsightly, but is a visible sign of aging connective tissue proteins throughout the body.
  • This occurs as a result of a decline in the body’s production of keratin and collagen.
  • Insufficient intake of specific vitamins and minerals further contributes to the loss of essential structural proteins.
  • Many of these changes can now be prevented, slowed, or even reversed with a novel combination of bioavailable keratin and collagen, along with specific vitamins and minerals.

Evidence of Clinical Efficacy

Clinical studies have demonstrated real-world benefits of supplementing with solubilized keratin.

In 2010, scientists revealed the results of their study on female subjects who had damaged, fragile, and stressed hair to determine if an oral keratin supplement would be effective in strengthening hair and facilitating hair growth.9 The women took daily supplements of 500 mg of solubilized keratin, along with zinc, vitamin B3, copper, vitamin B5, vitamin B6, and biotin for 90 days.

The subjects’ hair was tested for integrity and strength using three standard ways of measuring hair quality: scanning electron microscopic photos (shows hair appearance), number of hairs lost after washing (indicates hair strength), and mechanical force on individual hairs (shows hair strength).

First, electron microscopic photos showed dramatic healing of individual hair shafts. At the beginning of the study, the photos indicated elevated, uneven cuticle surfaces, but by day 90 the photos showed a smooth, interlocking, watertight cuticle. This change translates into smoother, shinier hair.

In addition, the number of hairs lost during washing was significantly reduced by 30% and hair strength increased by 12%. The researchers concluded that the keratin supplement strengthened hair, promoted hair growth, and improved hair appearance.

Hair and Nail Improvements

A 2014 randomized controlled trial found that the same keratin formulation was effective for decreasing the rate and amount of hair loss and improving the strength and appearance of nails in adult women.10

Subjects were women between 40 and 71 years old who had clinical signs of damaged hair and nails. They took two capsules of solubilized keratin or a placebo daily for 90 days.

By day 90, the researchers observed the following improvements:

  • 47.1% subjective improvement in hair appearance
  • 5.9% improvement in hair strength
  • 9.2% increase in hair follicles in the growth phase (the placebo group had no significant increase)
  • 47% reduction in the number of hairs that could be removed from the scalp in a hair-pull test, an evaluation in which 20 to 60 hairs are grasped between the fingers and firmly tugged away from the scalp to see how many can be removed

At the structural level, the amino acid composition of hair protein changed favorably in the supplemented group.10 By day 90, all four amino acids tested had a statistically significant increase showing the bioavailability of solubilized keratin.

Nail parameters were also significantly improved in the test group.10 Supplemented subjects showed an 87.5% improvement in the tendency of their nails to break, compared with 28.5% in the placebo group.

Five additional nail health parameters showed significant improvements for the supplemented group compared with baseline:

  • Hardness improved 50%
  • Resistance to bending and breaking increased 54.2%
  • Maintenance of overall nail integrity improved 33.2%
  • Nail smoothness increased 37.5%
  • The white, or natural, appearance of the nail improved 20.8%
Why Keratin Is Important
Why Keratin Is Important

Keratin is an important component of hair, skin, and nails.

The hair shaft is made primarily of keratin. The age-related decline in keratin synthesis leads to deterioration of stability and flexibility24 of the hair shaft, leaving hair vulnerable to dryness and breakage with brushing and the use of styling products and tools.

Similar to the hair shaft, the human fingernail is made almost entirely of keratin.25,26 As we age and produce less keratin, fingernails become brittle, resulting in splitting and fissuring. Nails can also develop yellow or gray discoloration and become dull or opaque in appearance.

These changes can occur as a result of various factors, such as circulatory changes that reduce the delivery of nutrients to the nail bed, exposure to the sun’s ultraviolet radiation, which damages the cell replication process, repetitive cycles of wetting and drying, and exposure to cosmetic and other chemicals.27 These and other factors, in addition to loss of keratin content, result in impairment of the intercellular adhesion that maintains the integrity of the nail plate.1

Keratin is also largely responsible for making skin strong, waterproof, supple, and flexible. Skin strength and resistance to tearing and penetration comes from an abundance of tough, but flexible fibers of keratin in the epidermis, the outer layer of the skin. Keratin cells and fibers also maintain the moisture content of the skin by providing a waterproof yet water-retaining barrier.

As we age, the cells that produce keratin are slower to renew themselves and progress through the skin layers to the surface. This causes the skin to become vulnerable and much of the waterproofing and water-retaining properties of the protective outer layer are lost. The result is a dry and dull appearance.3,28

Dry skin associated with lower keratin content creates more than just appearance problems. Dry skin causes itching and irritation that can lead to scratching and excoriation, further compromising the health and integrity of skin.29

The age-related decline in keratin production makes supplementing with this compound extremely important for preventing or reversing many of these seemingly cosmetic signs of age.

Keratin Improves Skin Appearance

In 2013, the same keratin formulation was evaluated in a randomized, double-blind, placebo-controlled clinical trial to determine its effectiveness in improving skin health and appearance.11

Subjects were females between 40 and 71 years old who already showed signs of skin aging. They took two capsules of solubilized keratin or a placebo daily for 90 days. Researchers determined that the supplement improved skin moisture, reduced wrinkle depth, and improved skin elasticity.

By day 30, subjects had already achieved a statistically significant 13.3% improvement in skin moisture. By day 60, there was a 22.2% improvement, and by day 90, there was up to 30.4% improvement in skin moisture. Interestingly, placebo recipients showed a decrease in skin moisture at these times.

Women taking the keratin supplement also experienced almost a 12% reduction in wrinkle depth after taking the keratin supplement for 90 days. This translated to visible improvements in wrinkle depth in 58.3% of subjects, significantly more than the placebo group.

By day 90, skin elasticity was improved 16.8%, skin smoothness improved 17.9%, and skin roughness decreased almost 9% when compared to the placebo group.

Supporting Healthy Skin from Within

In addition to keratin, collagen is vital for healthy, vibrant skin. Collagen makes up 70% of the weight of the dermis,12 the inner layer of the skin, and provides supple flexibility and supports elastin, the protein that allows the skin to stretch and return to its original shape.

As with keratin, there is an age-related decline in the number of collagen fibers in the dermis. With time, the cells that produce collagen fibers slow down, and the remaining fibers stiffen, break, and begin to lose shape. Elastin fibers begin to fray and lose elasticity. This deterioration of collagen and elastin leads to a wrinkled and sagging appearance.3

In order to combat this problem, scientists have developed Bioactive Collagen Peptides® that provide building blocks for collagen synthesis and stimulate the production of new collagen and elastin in the extracellular matrix of the skin.13 This provides increased suppleness and elasticity to aging skin.

Animal studies show that hydrolyzed (partially broken-down) collagen peptides increase the expression of collagen, helping to produce stronger, suppler skin. Additionally, these collagen peptides reduce activity of metalloproteinase 2, a “protein-melting” enzyme that degrades collagen and hastens skin aging.14

In 2014, scientists conducted a double-blind, placebo-controlled study to evaluate the effectiveness of a collagen peptide oral supplement on clinical signs of aging skin.15 Subjects supplemented with either 2.5 or 5 grams of Bioactive Collagen Peptides® or a placebo for eight weeks, and researchers measured skin elasticity, moisture content, and roughness.

Both doses of the Bioactive Collagen Peptides® resulted in a 7% improvement in skin elasticity. Even four weeks after the last supplementation dose, the supplemented group retained higher skin elasticity than the placebo group. The improvement in skin elasticity was markedly greater in the subgroup of women aged 50 years and older.

Improves Wrinkles

A second double-blind, placebo-controlled study of the effectiveness of Bioactive Collagen Peptides® oral supplement was published in 2014.13 The primary focus of this study was to evaluate the effect on skin wrinkles and synthesis of the dermal matrix. Subjects were 114 women aged 45 to 65 years old. Skin wrinkles were measured regularly during the eight-week trial of daily oral supplementation of 2.5 grams.

At four weeks, the volume of eye wrinkles for the supplemented group had decreased significantly by 7.2%, compared with placebo recipients. At eight weeks, that difference had risen to 20.1%, a one-fifth reduction in the size of unsightly eye wrinkles.

The researchers for this study also measured the amount of texture- and flexibility-preserving structural proteins in the dermal matrix. The greater the content of these proteins, the healthier and suppler the skin appears. Supplemented subjects had a 65% increase in the accumulation of essential type-I pro-collagen and an 18% increase in elastin fibers.

Improves Wrinkles

Biotin Improves Nail Health

Ancient Remedy Solves Modern Energy Crisis 

Animal studies have demonstrated that biotin supplementation is especially beneficial for healthy nails and leads to improvement in the hardness and integrity of the nail structure.16

Biotin’s beneficial effects on the health and appearance of fingernails have been established for more than 25 years. As far back as 1989, a study of the effect of biotin on aged and damaged fingernails showed that daily supplementation with 2.5 mg of biotin yielded firmer and harder fingernails for 91% of treated subjects after approximately 5.5 months.17

A year later, a group of women with brittle, splitting, or soft fingernails received biotin supplements and were then compared to a control group with healthy nails.18 In the supplemented group, fingernail thickness increased by 25%, reaching the same degree of thickness as in the control group. Nail splitting was also reduced for the supplemented group. Electron microscopy revealed that the irregular arrangement of cells on the nail surface of brittle nails became more regular.

Finally, a small retrospective study in 1993 found that when 44 adults with brittle and splitting nails took 2.5 mg per day of biotin for at least one month, 63% of subjects experienced a clinical improvement in nail integrity, as shown by a decrease in the brittleness and splitting of the nail.19

Additional Collagen Support

Silicon is an essential trace element involved in the metabolism of connective tissue.20-22 It plays an important role by activating the hydroxylation enzymes for cross linking collagen, supporting its elasticity and strength.23 Better collagen ultimately translates into better hair, skin, and nails.


The health and vitality of hair, nails, and skin begins with the health of the tissues that comprise them. Expensive cosmetics will only temporarily cover the telling signs of a tired and aging body.

An entirely different approach is to nourish the aging body’s vital structural proteins from within by strengthening the essential keratin and collagen needed to sustain structural integrity and an attractive appearance.

A novel, oral formulation of specialized bioavailable collagen and keratin, plus biotin, silicon, and other micronutrients, has been shown to support healthy protein structures at both the microscopic and the visible levels. These changes, while visible to the eye, represent a much deeper shift in the protein structure and composition of the entire body.

Health and beauty reflected in hair, nails, and skin can only be truly achieved from within, and many of the changes that are often seen as an inevitable part of aging, can be prevented and even reversed now that essential proteins can be restored by oral supplementation.

If you have any questions on the scientific content of this article, please call a Life Extension® Health Advisor at 1-866-864-3027.


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