Life Extension Magazine®

Woman blowing bubbles taking oral supplement of collagen peptides and keratin for skin and hair

Fight Back Against Visible Signs of Aging

Oral ingestion of collagen peptides, solubilized keratin, and other nutrients helps restore skin, hair, and nails.

Scientifically reviewed by: Dr. Gary Gonzalez, MD, in August 2023. Written by: Michael Downey.

Visible deterioration of hair, skin, and nails used to be unavoidable.1-3

But there are ways to stop and even reverse this deterioration.

A factor involved with external degeneration is the loss of our structural foundations.4-7

The most well-known of these structural proteins are:

  • Keratin, a component of hair, nails, and the outer layer of skin,
  • Collagen, the principal source of the skin’s strength, and
  • Elastin, which allows tissues to resume their shape after stretching or contracting.

While thousands of dollars are often spent on external treatments, overlooked are oral compounds that have been shown to replenish these vital structural proteins in the hair, nails, and skin.

A Keratin Breakthrough

There’s a longstanding problem with taking oral keratin supplements to replace declining keratin levels in the body. The heat and other factors normally needed to process keratin rob it of its biological activity, rendering it all but useless.

But scientists have developed a form of keratin that is soluble and highly bioavailable.

This solubilized keratin is delivered to cells in the hair, skin, and nails. There, it replenishes keratin levels depleted in the aging process.8-10

Laboratory studies show that solubilized keratin stimulates skin cells to proliferate at a rate up to 160% greater than they otherwise would, helping cells increase their own production of diminished structural proteins.10

Clinical Keratin Studies

In a series of clinical trials, adult women were given either a daily placebo or 500 mg of solubilized keratin with additional vitamins and minerals (biotin, zinc, copper, and vitamins B3, B5, and B6).

After 90 days, clear improvements were seen to hair, skin, and nails, as demonstrated by the following results:

In one study of women with damaged, fragile, and stressed hair, the number of hairs lost during washing was reduced by 30%, hair strength increased by 12%, and hair appeared smoother and shinier.11

In another trial, those who took this keratin had a:12

  • 47.1% subjective improvement in hair appearance,
  • 47% reduction in the number of hairs that could be removed in a hair-pull test, and
  • 9.2% increase in hair follicles in the growth phase.

Those taking novel keratin also had the following significant improvement to their nails:12

  • 87.5% reduction in tendency to break (compared with 28.5% among placebo subjects),
  • 50% increase in nail hardness,
  • 37.5% increase in nail smoothness, and
  • 20.8% improvement in natural appearance.

For women (ages 40-71) with obvious skin aging, the same keratin formulation reduced the appearance of lines and wrinkles, resulting in a:13

  • 30.4% increase in skin moisture,
  • 16.8% improvement in skin elasticity,
  • 17.9% improvement in skin smoothness, and
  • Visible reduction in wrinkle depth among 58.3% of participants.

Collagen’s Vital Role

Collagen is a major component of nails and skin. It normally comprises 70% of the weight of the dermis, the inner layer of the skin.14

Collagen provides the structural foundation for elastin fibers, a key requirement for supple, flexible skin.

Aging decreases the number of collagen fibers in the dermis and causes elastin fibers to fray and lose elasticity. This deterioration leads to wrinkled and sagging skin.15

Restoring depleted collagen is not as simple as ingesting more collagen. The collagen first needs to be partially broken down through a special process in order to be bioavailable (absorbable).

Researchers developed a blend of bioactive collagen peptides (short chains of amino acids), derived from type I collagen, which is the most abundant form of collagen in the human body.

These highly bioavailable collagen peptides provide the building blocks for collagen synthesis and stimulate collagen and elastin production in the skin.16

They also protect the skin by reducing the activity of metalloproteinase 2, a “protein-melting” enzyme that breaks down collagen and hastens skin aging.17

The effect is a dramatic reduction of skin wrinkles.

Scientists have also clinically demonstrated that these collagen peptides accelerate nail growth, reduce nail brittleness, and decrease frequency of nail breakage.18

Collagen’s Clinical Benefits

Results from two placebo-controlled trials of female volunteers found that taking 2.5 grams of bioactive collagen peptides once daily for eight weeks resulted in healthier, more supple skin.

Among the improvements were a:16,19

  • 20.1% reduction in wrinkle depth,
  • 65% increase in the accumulation of type I pro-collagen (a precursor of collagen),
  • 18% increase in elastin fibers, and
  • 7% improvement in skin elasticity (which persisted four weeks after treatment stopped).

A third study found that taking 2.5 grams of bioactive collagen peptides daily for six months reduced cellulite in women by 9% and decreased thigh skin waviness by 11.1%.20

In a trial testing the effect on nails, healthy women who took 2.5 grams of bioactive collagen peptides once daily for 24 weeks had a:18

  • 12% increase in nail growth rate,
  • 42% decrease in the frequency of broken nails, and
  • 64% reduction in brittleness.

Remarkably, four weeks after treatment ended, this reduction in brittleness extended to 88% of participants. This likely resulted from the effect of the peptides on the nail matrix.18

A whopping 80% of participants agreed that the collagen peptides improved their nails’ appearance and expressed complete satisfaction with the results.18

Biotin For Better Nails

Two other nutrients can act as catalysts in helping to rebuild damaged structural tissues: biotin and silicon.

A water-soluble B vitamin, biotin has been shown in animal 21 and human22-24 studies to improve the hardness and integrity of nails.

In one study, taking 2.5 mg of oral biotin daily for an average of 5.5 months increased the firmness and hardness of aged, damaged nails in 91% of subjects.22

In a similar study on women with brittle, splitting nails, taking 2.5 mg of biotin daily for at least one month improved nail integrity, brittleness, and splitting in 63% of subjects.24

A third study of women with brittle and splitting fingernails showed that oral biotin reduced nail splitting and increased nail thickness by 25%.23

What you need to know

Healthier Skin, Hair, and Nails

  • Over time, the quality of our hair, skin, and nails deteriorates, leading to visible signs of aging.
  • This occurs as a result of a decline in the quality and amount of the essential structural proteins keratin, collagen, and elastin.
  • Taking highly bioavailable forms of solubilized keratin and collagen peptides can replenish these structural proteins.
  • Results from clinical studies show that taking these compounds can reduce skin wrinkle depth by 20.1% and improve the strength, growth, and appearance of hair and nails.
  • Two other nutrients, biotin and silicon, have been documented to complement these rejuvenation effects.
  • Research shows that these oral ingredients can reverse the visible signs of aging that occur in hair, skin, and nails.


Silicon also helps keratin and collagen to rebuild the cellular architecture of hair, skin, and nails.25-28

Scientists have suggested that hair strands with higher silicon content fall out at a lower rate and display greater brightness, and studies show that silicon use may improve hair strength and strands’ resistance to breakage.28

It is also associated with the synthesis of glycosaminoglycans, molecules that help create the substance that fills the space between collagen and elastin.26,28

Silicon is one of the most abundant minerals in the composition of nails.29 Soft and brittle nails can be an indicator of silicon deficiency.28

Taken together, keratin, collagen peptides, biotin, and silicon show great promise for rejuvenation of skin, hair, and nails, and reversal of visible signs of aging.


The loss of the amount and function of structural proteins as we age leads to thinning hair, sagging and wrinkled skin, and brittle, breakable nails.

Scientists have developed forms of keratin and collagen that are taken orally and help restore structural proteins from within, helping tomaintain youthful structure and function with age.

Two additional nutrients, biotin and silicon, help restore the architecture that supports healthy hair, youthful-looking skin, and stronger nails.

These compounds can improve the strength, growth, and health of hair and nails, increase skin moisture and elasticity, and significantly reduce skin wrinkles.

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


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