A four capsule serving of Flex Naturally™ contains 500 mg of collagen from chicken cartilage. Collagen from chicken cartilage contains natural ocuring type II collagen, chondroitin sulfates A, B, and C, and hyaluronic acid (HA).1 It also contains glucosamine sulfate and amino acids including l-lysine, l-proline, and hydroxyproline promoting cartilage synthesis, synovial fluid's lubricating qualities and production of collagen for healthy tendons, ligaments, muscles, and bone supporting healthy joint function and comfort.

Chondroitin Sulfates and Their Role in Joint Health
Chondroitin sulfates are proteoglycans manufactured within the cartilage matrix. They are made up of repeating derivatives of glucosamine sulfate held together by attached sugar molecules called disaccharides with the average length of the chain consisting of 25 to 30 repeating disaccharide units. In order to maintain healthy production of chondroitin sulfates, glucosamine sulfate is required. Chondroitin sulfates, along with glucosamine sulfate, help to attract and keep water in the cartilage. Cartilage is 80% water and is vital for keeping the cartilage flexible and shock absorbent. If the cartilage loses too much water, it will lose it’s shock absorbent qualities and deteriorate, forming cracks and will wear away until eventually there is bone on bone.2 They also inhibit destructive enzymes from breaking down healthy cartilage and stimulate the production of collagen, gylcosaminoglycans and other proteoglycans, which are needed to maintain healthy cartilage.3

Why Flex Naturally™ contains no added Bovine Chondroitin Sulfate
Research with chondroitin sulfate from bovine trachea, pig, and sea cucumber has demonstrated very little benefit in the treatment of arthritis. That's because the chondroitin sulfate molecules are too large to pass intact through the human digestive tract. And, if any chondroitin sulfate molecules did manage did get into the blood stream they are still too large to pass through the synovial membrane which surrounds the joint capsule to be delivered to the cartilage cells. While glucosamine has an absorption rate of 90% to 98%,4, 5 chondroitin sulfate has been calculated to be anywhere from 0 to 13%. 6, 7 That’s because chondroitin sulfate contains a mixture of intact and partially hydrolyzed GAGS (glycosaminoglycans) of molecular weights ranging in size from 14,000 to over 30,000. This means chondroitin sulfate is 50 to 300 times larger than glucosamine sulfate.

Researchers Find No Proof Chondroitin Sulfate can be absorbed When Taken Orally
In one study researchers administered 1 gram (1,000 mg) of chondroitin sulfate orally to human subjects. If any chondroitin sulfate was absorbed it would be indicated by increased serum GAG (glycosaminoglycan) concentration based on a highly sensitive indicator of intact or depolymerized GAGS. The test demonstrated that no level of chondroitin sulfate had successfully entered the blood stream through the digestive tract.

The results of this test led the researchers to conclude, “We suggest that chondroprotection by orally administering chondroitin sulfate is a biologically and pharmacologically unfounded theory.”8 After further analysis on the use of chondroitin sulfate, they concluded,”Pooled literature on chondroitin sulfate biochemistry offers enough information to assert that neither intact or polymerized chondroitin sulfate is absorbed by the mammalian digestive tract. Therefore, any direct action of orally administered chondroitin sulfate on cartilage and chondrocytes is not possible.” 9

Natural Occurring Silica in Chondroitin Sulfate
It is interesting to note that while researchers say that chondroitin sulfate cannot be absorbed in the digestive tract many people with arthritis say that they benefit from it. Also, besides improving arthritic symptoms, chondroitin sulfate has been used to treat cardiovascular disease, in particular the removal of atherosclerotic plaque.

If chondroitin sulfate cannot be absorbed, then how can it be beneficial? In a publication entitled , “Trace Elements, Hair Analysis and Nutrition”, published in 1983 under the auspices of Dr. Richard Passwater and Dr. Elmer M. Cranton on page 217, please note what it says about chondroitin sulfate and silicon;

Since several components of collagen (structural polysaccharides such as chondroitin sulfate and hyaluronic acid) contain 300 to 550 parts per million of bound silicon, this silicon may be cross-linking these molecules, increasing their size and stability.9 As a result, the structural stability of such tissues as skin and arterial and stomach linings could be improved by silicon. Arterial linings which have been stabilized by this chemical cross-linking may be less susceptible to small injuries that can initiate atherosclerosis. The silicon content of arteries declines by more than half over the first forty years of age or in atherosclerosis, even though the chondroitin sulfate content does not. 10, 11

Several studies have shown that wherever atherosclerotic plaque is found in human arteries, there is a considerable decrease in silicon in that artery in comparison to arteries without plaque.'2 One study of persons over sixty years of age determined the difference. There was fourteen times as much silicon in disease-free arteries as in atherosclerotic arteries.' 5 There was also a significant difference in the amount of silicon in the blood.

Trace mineral researcher Herbert H. Boynton points out:

"The biological mechanisms by which chondroitin sulfate and other silicon compounds alleviate cardiovascular disease are not well known at this time. It may be that they architecturally strengthen the walls of the arteries and render them resistant to fatty infiltration, and it may be that they inhibit the synthesis of an enzyme called hyaluronidase. Hyaluronidase causes the degradation of the collagen-like, silicon containing material which forms the interior of the blood vessels."

Mr. Boynton further emphasizes:

"There is a clear and almost invariable relationship between the amount of silicon in the aorta (the chief artery) and the degree of atherosclerotic deposits in the aorta: If silicon is high, the arteries are clear. If silicon is moderate, there is moderate atherosclerosis. If silicon is low, atherosclerosis is severe. It would seem, then, that adding biologically available silicon to the diet might well be helpful in preventing or alleviating atherosclerosis. Experimental evidence confirms that this is true."

In a number of clinical trials, Dr. L. M. Morrison and B. H. Ershoff of the Institute for Arteriosclerosis Research at Loma Linda University have shown that chondroitin sulfate, a natural collagenlike substance rich in silicon, has been dramatically successful in reducing the symptoms of heart disease associated with atherosclerosis. Similar experiments have been conducted with equally impressive results by a team of Japanese physicians headed by Dr. Kenjiro Izuka. Chondroitin sulfate greatly lessens the chest pains associated with heart disease and also reduces serum cholesterol levels. Jacqueline Loeper, a French researcher, duplicated Morrison, Ershoff and Izuka's tests with the same results. However, she used inorganic compounds of silicon rather than chondroitin sulfate. 16

Please Note: While some people may say that they receive some benefit from taking chondroitin sulfate it is more than likely because of the natural occurring silica as well as the sulfur molecule, and not the large GAG molecules. Silica and sulfur are used by the body to maintain healthy cell structures such as found in the bone, cartilage, tendons, ligaments, muscles, connective tissue, and even the synovial fluid. And if these two elements become deficient it would have a negative impact on the structure and function on all of these tissues resulting in poor lubrication of the joints, and bone, joint, and soft tissue deterioration.

Chondroitin Sulfate Levels Elevated in Arthritic Joints
It’s interesting to note that chondroitin sulfate levels in synovial tissues are usually elevated in patients with osteoarthritis.10 That being the case, trying to introduce chondroitin sulfate from an outside source would be of no direct benefit.

Glucosamine Sulfate Important for Healthy Production of Chondroitin Sulfate
Over 30 years of research has proven that glucosamine sulfate is vital for stimulating the healthy production of chondroitin sulfates within the cartilage matrix. If the amount of glucosamine sulfate is inadequate, the production of healthy chondroitin sulfates and other critical proteoglycans will diminish causing the deterioration of the water holding matrix.11 Since glucosamine sulfate has an 90 to 98% absorption rate 4, 5 compared to chondroitin sulfate, which is 0 to 13%, 6, 7 it makes far more sense from a biological point to take glucosamine sulfate stabilized with sodium, MSM (a source of organic sulfur), and Collagen II from chicken, which have all proven to be far more beneficial and effective in stimulating the natural production of healthy chondroitin sulfates and other proteoglycans essential for maintaining healthy cartilage.