© Whole Foods Magazine

April 2005


Bioactive Silicon (OSA) Improves Aged Skin and Reduces Wrinkling:

An interview with Drs. Dirk Vanden Berghe and Andre Barel.


Richard A. Passwater, Ph.D. and Richard Passwater, Jr.



            Bioactive silicon is of great importance to our health in several ways. A new study verifies that silicon’s systemic absorption of bioactive silicon as choline-stabilized orthosilicic acid (ch-OSA) produce rapid results actually observable and measurable by reduced skin wrinkling as well as internal health benefits. These measurable indicators include improved nail appearance and healthier osteoporosis-resistant bones. A new clinical study shows that in just 20 weeks, shallow wrinkles improved by up to 30% and skin elasticity improved by 55%, as well as a significant reduction of brittleness in nails and hair. Also, we have new information as to how silicon works to bring about these benefits.


I have invited silicon experts, Professor Dirk Vanden Berghe of the University of Antwerp (Belgium) and Professor Andre Barel of the Free University of Brussels (Belgium) to discuss their research with us. In this two-part discussion, we will look at how skin health indicates the health of internal organs and blood vessels and how silicon is critical to skin health. In Part 1, we’ll review the role of silicon in giving skin its healthy, youthful look, and in Part 2 we’ll discuss the clinical results of this new study that show that silicon supplementation as choline-stabilized orthosilicic acid (ch-OSA) reduces wrinkling and improves skin and nails


            In December, we had a conversation with Dr. Vanden Berghe about the essentiality of silicon to humans. He informed us about how silicon is a main support element for life and how silicon is important to the strength of our blood vessels, organs, skin, hair and bones. We discussed how the biologically active form of silicon, choline-stabilized orthosilicic acid (ch-OSA), provides chemical links within and between polysaccharide chains of glycoaminoglycans (GAG) including glucosamine, hyaluronic acid, chondroitin sulfate and other GAG.


            These silicon links formed by ch-OSA are important not only to structural strength, but also to skin health. Skin health is dependent of skin nourishment which is effectively achieved by dietary ch-OSA. Skin beauty on the surface (epidermis) is determined by the underlying tissue (dermis and hypodermis). Many people are silicon-deficient which results in rough, dry and wrinkled skin. It is a good practice to regularly use moisturizing lotions, aged and dry skin is help comparatively little compared to what can be achieved by internal nourishment. As people age, their skin usually decreases in silicon content due to diet. This appears to be a major contributing factor to dry skin and wrinkling. 


            What we perceive as “beautiful skin” is skin that is smooth and resiliently tight (elastic). This is a function of collagen (the main skin protein) and water content. Collagen production is not merely a matter of eating the right proteins and amino acids, but also the nutrients that facilitate collagen production such as silicon and vitamin C. The collagen should be properly supported with silicon-based links and aldehyde links, and not improperly cross-linked by random free-radical damage. So, skin collagen and water content are silicon-dependent. The questions we examine here are “will silicon supplementation slow wrinkling and decrease existing wrinkles.”


            Dr. Vanden Berghe is a professor on the Faculty of Pharmaceutical, Biomedical and Veterinary Sciences at the University of Antwerp in Belgium. He is also the holder of various international patents on antimicrobial compounds and food supplements and has authored more than 250 international publications with peer review. Professor Vanden Berghe is also an internationally recognized expert on the biological activities of flavonoids and other natural compounds. 


Prof. André O. Barel is Head of the Laboratory of General and Biological Chemistry and professor of Chemistry, Biochemistry, Oral Biochemistry, and Cosmetic Sciences, at the Faculty of Physical Education and Physiotherapy, Free University of Brussels (VUB), Belgium. He is the author of numerous book chapters, publications, and abstracts in dermato-cosmetic sciences and is a member of the executive committee of the International Society for Bioengineering and the Skin and the Société Francophone d'Ingérie Cutanée. He is also a consultant for international dermatological and cosmetic companies.

Passwater and Passwater: What is the importance of realizing that a deficiency in silicon can be indicated by skin health?


VANDEN BERGHE: First of all it should be mentioned that skin health itself is very important. Many health problems are reflected in the skin. The skin is the largest organ in the body. An adult’s skin is 15 to 20 percent of total body weight. Skin performs several vital functions. Foremost, it serves as a protective barrier between internal organs and external environment. Healthy skin impedes the penetration of microorganisms which can cause infections and protects against irritants. 


            A good support of skin by the underlying connective tissue is essential for skin function. Connective tissue is composed of cells which produce the fibrous protein matrixes of collagen and elastin, as well as the hydrated (water retaining) network of amino-sugars called glycosaminoglycans (GAG). Silicon is an essential element of this connective tissue as it determines the quality of the cells connected with its structure[1]. Furthermore, silicon is required for the structural integrity of connective tissue which was demonstrated in the 1970s by Drs. Carlisle1 and Schwarz[2] where silicon is believed to act as a cross-linking agent which stabilizes the glycosaminoglycan network.


To answer your question, because of the importance of silicon to the formation of connective tissue, fibroblasts and collagen[3]; signs of silicon deficiency can be observed as skin, hair and nails deterioration such as aged skin, increased hair fall-out and brittle, dry nails.


Passwater and Passwater: Don’t laugh, but technically, just what are wrinkles? Yes, we all know what they look like and we know one when we see one. But, Dr. Barel, what is different about wrinkled skin compared to healthy non-wrinkled skin?


BAREL: Wrinkles are modifications of the skin surface occurring with age. The severity of these changes in an individual depends on genetic tendency, skin photo- type and exposure to environmental factors. Wrinkles arise because of a modification in dermis structure (less collagen versus young skin) and because of a decrease in the amount of water held by the epidermis.


Passwater and Passwater: Scientists studying skin refer to wrinkles and microwrinkles. Just what is a “microwrinkle?” What is the difference between skin “roughness,” “microrelief,” “fine lines” and “microwrinkles.”


BAREL: The relief of the skin surface reflects the three-dimensional organization of the epidermis, dermis and the subcutaneous tissue. The skin microrelief is not visible with the eye but comprises a number of lines (‘primary’ and ‘secondary’ lines) which can be classified according to their depth (generally in microns) and respective orientation.

These micro lines or micro wrinkles can become the location for the macro lines or wrinkles (depth of 1–2 mm), also known as the macrorelief. There is no precise classification of the different types of wrinkles, and different names (lines, furrows) are used as a synonym for wrinkles in conjugation with the adjectives “fine, small, thin” to better qualify them.

Skin roughness, in a physical sense, means a surface with lines of certain width and depth that can be quantified by roughness parameters. Thus, aging skin with fewer and deepened lines will be defined rougher, although it is not necessarily rough to touch.


Passwater and Passwater: Most people think of wrinkles as being caused by aging. However, time alone has no effect on skin. Time is merely the fourth dimension. All people of the same age do not have identically wrinkled skin. The exposure of skin to sunlight increases free radical damage and the cross-linking of skin proteins. The damage resulting from these reactions between ultraviolet energy from the sun and skin proteins accumulate over time. It’s a product of the rate of reactions (intensity) and length of time of exposure. Antioxidant deficiency also increases the rate of wrinkling.

What does silicon have to due with reducing wrinkling?


VANDEN BERGHE: It is important both to have a good skin structure and to prevent damage to that structure. While sun can damage skin, so can the lack of underlying structure in the first place. When the support structure (e.g. connective tissue) of the skin begins to collapse, this causes wrinkles and lines. Biological silicon in the form of choline-stabilized orthosilicic acid (ch-OSA) is very important to skin structure. Skin is dependent on silicon for producing its skin proteins and maintaining its water content, but I will come to that in detail later. Poor quality skin, deficient in collagen and lacking water, has poor underlying structure which results in wrinkles.


Passwater and Passwater: We have long known from animal studies that silicon is important to collagen production. This has been from basic gross observational studies. Have we learned more details about the biochemistry involved?


VANDEN BERGHE:   Our understanding of silicon biochemistry is growing. Animal studies have shown that silicon deficiencies cause collagen deficiencies including bone deformities[4],[5]. Cell culture studies[6] are helping us understand some of the roles of silicon-dependent enzymes[7], observational trials showing favorable correlations between silicon consumption and connective tissue health and intervention trials supplementing animals[8],[9],[10],[11] with silicon are also yielding favorable results associated with connective tissue health. Furthermore, recent research shows that silicon influences TNF-a and hence collagen gene promoter activity[12].

As an example, Figure 1 illustrates the results from one of our previous animal studies showing where a five percent increase in dietary silicon as stabilized ch-OSA biologically amplifies collagen production by 12 percent11 in the dermis.



Passwater and Passwater: Well that explains why a little extra ch-OSA has such a big effect on skin. The fact that silicon affects the enzymes that produce collagen, rather than becomes a part of collagen structure, explains this biological amplification. For years we have looked for silicon-containing compounds within collagen. We were looking for instances where silicon atoms replaced certain carbon atoms in collagen. We reasoned that since silicon – carbon bonds were stronger than carbon-carbon bonds, then silicon atoms substituting for carbon atoms in the amino acids that make up collagen would make the collagen stronger, and thus, the skin better. We’ll come back to this point later.


We have learned of the relationship between silicon and enzyme activity only in the past few years. Enzymes are not consumed in reactions but serve as reusable catalysts that cause the reactions to occur. So enzymes repeat their task over and over. In the case of collagen, the needed quantity of two enzymes required for collagen production are small in comparison to all of the collagen that they make. But, if the actions of these two enzymes are impaired by silicon deficiency, the difference in collagen production can be great. Conversely, a small amount of additional dietary ch-OSA to stimulate or facilitate the efficiency of these two enzymes can significantly improve collagen production.


            Before we look at this new information closer, let’s start at the beginning with the role of collagen in skin health. Please elaborate on why collagen production is important to the health, look and feel of skin. Where is collagen produced? Epidermis, dermis or Hypodermis?


BAREL: Figure 2 is a cross sectional view of the skin showing the epidermis, dermis and hypodermis. A skin cell, formed in the basal layer (a single layer of basal cells) migrates upwards for about two weeks until it reaches the upper layer of the skin, known as the epidermis. The cell spends another two weeks in the epidermis, gradually flattening out and continuing to move upwards. Then the skin cell dies and is shed off the surface. Two to three billion skin cells are shed every day – in fact, they make up a substantial percentage of household dust.


Collagen is produced in the dermis by fibroblasts and influences the maturation of the dermis. Collagen makes up 25 to 35% of the total protein of mammals. It has great tensile strength, and is the main component of ligaments and tendons. Collagen forms long molecular cables that strengthen tendons and the vast, resilient sheets of connective tissue that support the skin and internal organs.


Collagen molecules assemble themselves into ordered polymers called collagen fibrils. Figures 3 and 4 show how collagen molecules are intertwined to form fibers that form a matrix. All contain a long stretch of triple helix connected to different types of ends. The simplest is merely a long triple helix, with blunt ends.



As mentioned before silicon is important for optimal collagen synthesis and crucial for activating the hydroxylation enzymes for cross linking collagen, which improves the strength of collagen. Collagen is actually a family of proteins that act as a “glue” to hold the body together. There are at least 19 different types of collagen proteins known and each type has a different molecular composition and shape. These collagen family members are simply designated as type I, type II. etc. The main types of collagen found in skin and connective tissue are types I, II, III, V and XI, with type I being the principal collagen found in skin and bone and by far the most common in the body. These have rope-like structures and are called “fibrillar collagens.” These fibrillar collagens associate side-by-side, like fibers in a rope, to form tough fibrils. These fibrils crisscross the space between nearly every one of our cells.


About one-sixth of the body consists of spaces between cells. This space is called the interstitium and the gel-like fluid that fills this space is called interstitial fluid. Collagen fibers extend long distances in the interstitium. These collagen fibers provide most of the tensional strength of the tissues.

            As Figures 3 and 4 show, collagen is composed of three chains, wound together in a tight triple helix. The collagen chain is over 1400 amino acids long essentially consisting of repeated sequences of three amino acids – proline, hydroxyproline and glycine. Other amino acids, including hydroxylysine, are also found in different types of collagen, thereby giving the various types of collagen their specific shapes.


Because both proline and hydroxyproline are rigid, cyclic amino acids, they limit rotation of the protein backbone and thus contribute to the stability of the triple helix.  Hydroxyproline has an essential role in stabilizing the triple helix of collagen by hydrogen bonding between the hydroxyl groups and water. Hydroxyproline is created by modifying normal proline amino acids after the collagen chain is built. The reaction requires vitamin C to assist in the addition of oxygen, and as we have learned recently, it also is dependent on silicon.


Passwater and Passwater: Now let’s go back and look at some of the new information. Tell us more about how silicon is involved in the production of collagen. Our understanding of silicon’s role in skin health has been hampered because many of us have always been looking for specific structural compounds that intrinsically contain silicon atoms. This is particularly true of blood vessels. For decades we have had evidence that silicon nourishment leads to healthier and stronger blood vessels. Yet, when we looked for silicon structural compounds, all that could be found were OSA and its chains. (Please see Figure 5)


We didn’t understand that these OSA chains were strong linking agents having hydrogen bonds that strongly crosslink collagen fibers. Seeing OSA and its chains in the tissue was akin to seeing nitric oxide in the blood and not understanding that it was an important biochemical messenger that plays a role in many biochemical functions. Now we understand that nitric oxide is important in blood vessel relaxation, as well as in memory and attention. Once considered irrelevant because of its molecular size and not a structural component, nitric oxide is now known as an extremely important molecule. Perhaps, as our understanding of OSA increases, so will the value we place on silicon.


            Please elaborate more about how silicon improves skin without forming a silicon-containing-amino acid such as silaproline or silahydroxyproline, or complex silicon-containing structural molecules that become interwoven with collagen.


VANDEN BERGHE:   There are a lot of studies that confirm the stimulating effect of silicon on collagen synthesis. Even more, there seems to be a connection between silicon and those cells in the extra cellular matrix responsible for collagen synthesis where silicon is essential for the quality of these cells ergo for the quality of their product of synthesis, the connective tissue.


Now how is silicon involved? This is our proposed dual action of silicon[13]: 1) silicon as choline-stabilized orthosilicic acid is absorbed in the gut from diet. ch-OSA is a neutral molecule in physiological conditions, it does not easily cross cell membranes by simple diffusion and flows through the body in the presence of water. ch-OSA can only become ‘activated’ in the proteoglycan sacs of the connective tissue. Connective tissue is composed of cells (fibroblasts, chondrocytes, osteoblasts, osteocytes, tenocytes, …) which produce the fibrous protein matrixes of collagen and elastin, as well as the hydrated (water retaining) network of amino-sugars called glycosaminoglycans (GAG). These GAG’s are negatively charged due to the presence of sulfate and acidic groups. Furthermore they form covalent bonds with a protein core what leads to the formation of a proteoglycan sac. These negatively charged GAG’s attract water, cations (such as K+, Ca2+ and H+) and positively charged polyamines. ch-OSA, only present in the water, is also attracted by the GAG’s and diffuses into the proteoglycan sac. Due to the flux of cations the negative charges of the GAG’s are partially neutralized resulting in polarization or ‘activation’ of ch-OSA. ‘Activated’ ch-OSA attaches to positive charged ions and to the positive charged aminosugars (arginine, lysine, histidine) and to the hydroxylated amino acids (serine, threonine, tyrosine). This leads to associations of ch-OSA, resulting in cross linkage of the GAG’s to a strong network with a water retaining capacity essential for a good working connective tissue. 2) Furthermore this ‘activated’ ch-OSA can be easily picked up by the cells in the connective tissue, where it stimulates the collagen synthesis.



A:  The dual action of ch-OSA:

(1)   Silicon is necessary for the formation of the water-retaining network of GAG’s . This is realized by conversion of neutral to ‘activated’ ch-OSA in the strong negatively environment of the GAG’s in the proteoglycan sac.

(2)   ‘Activated’ ch-OSA enters the cell and stimulates the synthesis of collagen and other components of the connective tissue.

B: The proteoglycan sac in detail:

The micro environment of the proteoglycan in the connective tissue can be viewed as a sac composed of GAG’s attached to a core protein. These GAG’s are negatively charged due to the presence of sulfate and acidic groups.


Passwater and Passwater: As we mentioned earlier, hydroxyproline is an amino acid that is an important component of collagen. The body can make proline which must be converted into hydroxyproline in the collagen structure to make proper collagen. Proline is not a dietary essential amino acid, as it can be produced in the body from the dietary essential amino acid glutamate. Now hydroxyproline is a story within itself. We always find hydroxyproline interesting. It is unusual to say the least.


            Hydroxyproline is found in the major protein collagen and only very rarely found in other proteins, but what is more interesting is that hydroxyproline is formed from proline only after the proline has been incorporated into proteins.


            What we especially find peculiar is that hydroxyproline is not coded for by DNA; it is produced by hydroxylation of the amino acid proline, yet it is essential for proper functioning of collagen. This would mean that our genes aren’t programmed for producing hydroxyproline, yet skin requires it and dietary hydroxyproline is of no value in supplying hydroxyproline because it appears that hydroxyproline cannot be directly incorporated into collagen. Instead, proline must first be incorporated into pro-collagen and then converted into hydroxyproline on the growing polypeptide chain. No wonder there are so many collagen-related diseases. About half of the proline is converted into hydroxyproline. Dietary hydroxyproline is converted into glyoxalate, pyruvate and ketoglutarate, rather than incorporated into proteins (Figure 7). So eating a lot of chicken skin for its hydroxyproline content or taking hydroxyproline supplements or cream won’t help much in terms of hydroxyproline for collagen synthesis.



            There are two forms of hydroxyproline in collagen, 3-hydroxyproline and 4-hydroxyproline. These are formed with the aid of the enzymes, prolyl 3-hydroxyproline and prolyl 4-hydroxyproline. Proline is mostly converted to 4-hydroxyproline with some converted to 3-hydroxyproline. Vitamin C is an essential cofactor for both prolyl hydroxyproline enzymes, as are iron, oxygen and alpha-ketoglutarate. Unlike an enzyme, vitamin C actually contributes portions of its structure to the process, but it gains that portion back through a recycling process with other compounds. Vitamin C is not just a reducing compound, but actually a redox couple (ascorbic acid / dehydroascorbic acid), which can undergo cycling. It is believed that in this reaction, the role of vitamin C is to maintain the enzyme’s iron co-factor in a reduced state at the active site. The reaction may proceed via the intermediate formation of a peroxyglutarate reacting with proline.


            And, now you are telling us that silicon is involved with these enzymes as well. This is important, because without the conversion of certain proline residues in the pro-collagen fibrils into hydroxyproline, the fibrils can not be bundled into the collagen stable triple helix, nor can they form normal fibers. If pro-collagen is not properly hydroxylated, the fibrils are degraded within the cell.


            Two other enzymes are involved with the conversion of the amino acid lysine in some types of collagens into hydroxylysine to form the proper structure within those types of collagen. The enzymes galactosyl-hydroxyllysyl glucosyltransferase and lysyl oxidase have also been shown to involve silicon by Dr. Poole and colleagues in 1985.


            The assembly of collagen fibers begins in a part of the cell called the rough endoplasmic reticulum, continues in the Golgi complex and is completed outside the cell. Several modifications to the pro-collagen chains must be made before the triple helix can be formed in the rough endoplasmic reticulum.


            It is well known that a lack of vitamin C in the diet can cause the skin lesions, fragile tendons and porous blood vessels of scurvy. This is because vitamin C is needed for collagen production, yet vitamin C is not part of collagen. Vitamin C is required for hydroxyproline production as a key cofactor in the enzymatic conversion of some of the proline incorporated into collagen precursor molecules into hydroxyproline step in collagen formation. Now, we know that silicon is involved as well. Although the enzyme contains copper, it is not activated by copper but by silicon through a mechanism that is not yet understood. This was first report by Dr. Edith Carlisle in 1986 and confirmed by Dr. Forrest H. Nielsen in 1996.


VANDEN BERGHE: Yes, according to cell culture studies, the activity of prolyl hydroxylase, the enzyme required for the hydroxylation of proline to form hydroxyproline, is dependent on silicon; thus collagen synthesis is silicon-dependent.


            In 2002, Drs. C. D. Seaborn and F. H. Nielsen10 published their study in which they implanted polyvinyl sponges beneath the backs of laboratory rats to monitor collagen formation. They found that in silicon deficient rats less hydroxyproline was deposited on the sponges compared to rats on a normal diet. This shows that silicon deprivation decreases collagen formation which is associated with wound healing.


Earlier you mentioned that proline was not dietary essential as it can be produced in the body from glutamate. It can also be produced via the ornithine pathway. Recent evidence implies that there is a widespread potential for proline synthesis from ornithine. Well, the activity of ornithine aminotransferase, an important enzyme of the ornithine pathway leading to the formation of proline and thus collagen formation, was lower in silicon-deficient rats compared to silicon-adequate rats10.


            In our calves study11 we measured the hydroxyproline concentration in the dermis of animals supplemented with ch-OSA and a control group given a placebo. The hydroxyproline concentration was statistically higher in the ch-OSA group. In skin both collagen type III and type I is found.



Passwater and Passwater: OK, professors, your biochemical review of the role of silicon in skin leads us to the point, “what are the results of your clinical study?” Let’s take a look at the study in the June issue.


© 2005 Whole Foods Magazine and Richard A. Passwater, Ph.D.

This article is copyrighted and may not be re-produced in any form (including electronic) without the written permission of the copyright owners.





[1] Carlisle (1974) Silicon as an essential element. Federation Proceedings, 33: 1758-1766.

[2] Schwarz (1973) A bound form of silicon in glycosaminoglycans and polyuronides. Proc Natl Acad Sci USA, 70(5): 1608-1612.

[3] Carlisle (1986) Silicon as an essential trace element in animal nutrition, Silicon Biochemistry, Wiley, Chichester: 123-139.

[4] Carlisle (1976) In vivo requirement for silicon in articular cartilage and connective tissue formation in the chick, J. Nutr., 106:478-484.

[5] Carlisle (1980) A silicon requirement for normal skull formation in chicks, J. Nutr., 110:352-359.

[6] Valerio et al. (2004) The effect of ionic products from bioactive glass dissolution on osteoblast proliferation and collagen production, Biomaterials, 25: 2941-2948.

[7] Reffitt et al. (2003) Orthosilicic acid stimulates collagen type 1 synthesis and osteoblastic differentiation in human osteoblast-like cells in vitro, Bone, 32: 127-135.

[8] Seaborn and Nielsen (2002) Silicon deprivation and arginine and cystine supplementation affect bone collagen and bone and plasma trace mineral concentrations in rats, J. Trace Elem. In Exp. Med., 15(3): 113-122.

[9] Nielsen and Poellot (2004) Dietary silicon affects bone turnover differently in ovariectomized and sham-operated growing rats, J. Trace Elem. In Exp. Med., 17(3): 137-149.

[10] Seaborn and Nielsen (2002) Silicon deprivation decreases collagen formation in wounds and bone, and ornithine transaminase enzyme activity in liver, Biol. Trace Elem. Res., 89: 251-261.

[11] Calomme et al. (1997) Supplementation of calves with stabilized orthosilicic acid, Biol. Trace Elem Res, 56: 153-165.

[12] Hull et al. (2004) Low dietary silicon increases TNF-alpha and collagen gene promoter activity in mice, Experimental Biology, Abstract 364.5.

[13] Vanden Berghe (2005) Proposed action of silicon, internal discussion.