Bone broths are highly valued for their benefits, especially for joints and the digestive tract. Name almost any major cuisine in the world and broths and stocks are essential components. In pre-late 20th Century households, these liquids provided the foundation for sauces, soups, stews and numerous other products of the kitchen. However, they went beyond this to provide the bases for nutrient rich tonic foods considered to be good for the bones, joints, digestive system, immune system and general vigor.

The traditional expectations of bone broths are given in numerous books and articles on the topic, but are unlikely to find substantiation as such on PubMed because modern medical research focuses on pure compounds and on items that can be patented. Bone broth benefits from the broths themselves generally are observations from history, not from the scientific literature. For those who are interested, a full history of gelatins and similar usage and science focusing on knowledge and use up to the end of the 19th Century can be found in Gotthoffer, NR, Gelatin in Nutrition and Medicine(Graylake IL, Grayslake Gelatin Company, 1945), which can be purchased as a Kindle edition on amazon. Another book on the topic worth reading is Nourishing Broth: An Old-Fashioned Remedy for the Modern World by Sally Fallon Morell and Kaayla T. Daniel. More history, but also modern science focusing on individual broth components is wonderfully reviewed in "Traditional Bone Broth in Modern Health and Disease," by Allison Siebecker in the Townsend Letter for Doctors and Patients (2005).¹

The benefits of traditional bone broth reflect an emphasis on the building blocks for tissues as the sources of repair. The idea is not to substitute for the body’s own mechanisms, but instead to assist the body in making its repairs. In line with this approach, collagen and gelatin components, such as chondroitin sulfate, found in bone broth support the tissues in the body that themselves are constructed or repaired from these components, for example, the joints and their cartilage, the skin, and connective tissues in general. Similarly, minerals from bone broth support or even stimulate the repair of various tissues. Keep in mind that bone broths traditionally were foods, which are to say, consumed in considerable quantity in gram amounts, not milligram amounts. Efficacy in milligrams only is important for tablets and capsules and often focuses only on the narrowest of ranges of benefits. Total Health has touched on this issue before in terms of the entourage effect (September 2015). This issue has been examined in medical circles, for instance, "Whole Food versus Supplement: Comparing the Clinical Evidence of Tomato Intake and Lycopene Supplementation on Cardiovascular Risk Factors."²

Bone Broth Nutrition Basics
Before examining one bone broth component–chondroitin sulfate–in depth, below is a short listing of the a few of the nutrients found in bone broths.

Amino Acids
Bone broths throughout history have been associated with healing, whether of the gut, the joints, or more generally in response to illness. Part of the reason for this involves immune-supporting amino acids. Depending on the broth, these include arginine, cysteine, glycine and proline. These are found in beef and chicken bones, marrow, etc. Fish broths offer different nutrient mixtures from those found in land-based animal broths. For those interested in the roles of proline and glycine in digestive health, the Weston Price Foundation has published "Why Broth is Beautiful/Essential Roles for Proline, Glycine and Gelatin."³

Collagen and Chondroitin
More specific nutrition factors include bioactive Type I and Type II collagen peptides and cartilage chondroitin sulfate. Collagen is the most abundant protein in humans, representing about 25-30 percent of total protein in the body. It is the main component of skin, cartilage, ligaments, tendons and bones. Glucosamine, chondroitin sulfate and hyaluronic acid (a component of Collagen Type II) are the chief components of the extracellular matrix.

Collagen Type I is associated with the preservation of bone mineral density; in conjunction with hydroxyapatite, it accelerates osteogenesis. There is a further association with the health of the immune system known as oral tolerance that may be important for joint health.

Collagen Type II is a low molecular weight, water-soluble glycosaminoglycan complex that supports joint health and skin hydration.

Chondroitin Sulfate acts like a biological version of a "liquid magnet," attracting fluid into proteoglycans, protein chains that form the basis of cartilage and the extracellular matrix. This fluid acts as a shock absorber and also brings nutrients with it into the cartilage. Perhaps of greater significance than its fluid-enhancing properties, chondroitin protects existing cartilage through its modulatory effects on enzymes that degrade cartilage. Furthermore, chondroitin stimulates the production of proteoglycans and collagen that are needed for healthy new cartilage.

Natural Cartilage Components Heal The Joints
A just released study in the Annals of the Rheumatic Diseases (May 2017) shows that a relatively small quantity of the supplement chondroitin sulfate is effective in improving the symptoms of osteoarthritis.⁴ Pitted against either the prescription drug celecoxib (Celebrex) or placebo in a blinded trial, 800 mg chondroitin sulfate per day led to improvements in pain and joint function that were significantly greater after six months (chondroitin sulfate) and three months (celecoxib). Joint function improved more quickly in patients taking celecoxib, but there were no overall differences in the effectiveness and the benefit-risk profile strongly favored the chondroitin sulfate treatment. These results should be viewed in light of a 2016 study that demonstrated in a 2-year randomized controlled trial that treatment with 1,200 mg per day chondroitin sulfate was superior to celecoxib in preventing cartilage volume loss.⁵

Such results offer the promise of help to large numbers of individuals. Joint pain and connective tissue injuries are amongst the most common complaints of older individuals and affect 15 percent or more Americans whom exhibit some form of arthritis. Not just the elderly, but even young and fit athletes through overuse can exceed the repair capacity of the joints. Non-steroidal anti-inflammatories (NSAIDS) can relieve pain and initially help with joint inflammation and swelling, yet at the cost of slowing healing and for some individuals causing irritation and bleeding of the stomach. This has led to a search for alternatives. The idea that natural compounds such as glucosamine and/or chondroitin sulfate might have therapeutic effects in treating osteoarthritis by providing the substrates for the repair of cartilage has been around since the mid-1950s. Major issues have included determining which forms and how much of such supplements are necessary for benefits. For instance, confirming earlier studies, research published in 2005 involving approximately 1,500 osteoarthritis patients demonstrated that a daily dose of 1,500 mg glucosamine hydrochloride in combination with 1,200 mg chondroitin sulfate was equally as effective with fewer side effects than 200 mg of prescription celecoxib in treating moderate to severe knee pain, albeit relief took longer to appear. At the same forum, it was reported that 1,500 mg glucosamine sulfate was superior to acetaminophen in relief. Both of these studies involved quite large dosages of supplements leaving open the question of whether such large amounts are necessary. The 2017 study demonstrated efficacy with a dose of chondroitin sulfate that was less than half of that which had been tested previously and shown to be effective.

Study Summary
Chondroitin sulfate is a sulfated glycosami¬noglycan composed of chains of alternating D-glu¬curonic acid and N-acetyl-Dgalactosamine.⁶ It is a major component of cartilage, a tissue in which it exists attached to proteoglycans. Proteoglycans are commonly described as looking like tree trunks with many branches to which are connected bottle brush-like bristles. Chondroitin sulfate is especially important in joint synovial fluid and for the fluid-retaining qualities of the proteoglycans.⁷ In the 2017 study, the primary issue was whether chondroitin sulfate could be effectively used for long-term treatment of osteoarthritis, in particular in an aging population.

For study purposes, 604 patients diagnosed with symptomatic knee osteoarthritis were randomly assigned to one of three daily treatments in what is known as a double-blind, double-dummy design. In the chondroitin sulfate group, 199 patients were given 800 mg chondroitin sulfate; the second group made up of 200 patients received 200 mg celecoxib; the third group consisting of 205 patients received dummy tablets. Pain, joint function, and overall patient acceptability were assessed using validated scoring systems on days 30, 91 and 182. Improvements in pain and joint function were significantly greater after six months (chondroitin sulfate) and three months (celecoxib). Joint function improved more quickly in patients taking celecoxib, but there were no overall differences in the effectiveness. The benefit-risk profile favored the chondroitin sulfate treatment, meaning benefits fewer or no side effects.

The authors of the study concluded that a daily dose of 800 mg of pharmaceutical-grade chondroitin sulfate was better than a dummy product and as good as celecoxib in reducing pain and improving joint function in symptomatic knee osteoarthritis. However, the researchers advised care in selecting the form of chondroitin sulfate utilized: "Chondroitin sulfate is available as pharmaceutical-grade and nutraceutical-grade products, the latter exhibiting striking variations in preparation, composition, purity as well as clinical effects." In other words, the quality of the vendor should be the guide to choosing a product.

Chondroitin Sulfate Heals More Than The Joints
Chondroitin sulfate has many roles in the body other than in contributing to the health of the joints. Connective tissues which depend upon chondroitin sulfate are widely dispersed, which is to say that they are found not only as cartilage, but also as bone, tendon, skin, blood vessel walls, and mucous membranes. Any one or all of these tissues may benefit from supplementation with chondroitin sulfate.

Atherosclerosis (hardening of the arteries) is a case in point. Over a six-year period in a study involving one hundred and twenty subjects already suffering from diagnosed atherosclerosis and undergoing medical treatment, the group which supplemented daily with 1,500 mg of chondroitin sulfate fared strikingly better. The supplemented group had only one third as many deaths (4 versus 13) and one seventh the number of total cardiovascular incidents of types (6 versus 42). Inasmuch as this study lasted for six years, the safety of a large daily ingestion of chondroitin sulfate also was shown.

Chondroitin sulfate has a number of effects that have been demonstrated, but not always clearly explained. For instance, mucopolysaccharides in some tests have proven to be interesting immunomodulators that increased immune activity when it was too low and helped to turn it down when it was too high, such as in autoimmune conditions. Chondroitin sulfate has anti-inflammatory benefits and wound healing benefits. Some tests have indicated that chondroitin sulfate can help to regulate normal cell division. The range of benefits becomes clearer when it is realized that the following items all contain forms of chondroitin: bone broths, bovine cartilage extracts, shark cartilage extracts, extracts from sea cucumber and the green-lipped mussel.

Conclusions
Bone broths no doubt date back to prehistoric times and are staples in a number of established medical systems, such as Traditional Chinese Medicine. The principles remain the same today as in centuries past. Mineral and protein-rich broths containing the building blocks of the digestive system and connective tissues are surprisingly versatile in helping the body to heal itself. Although modern medical research typically does not examine complex food such as bone broths, research into the benefits of individual components often yields impressive results. Chondroitin sulfate is a case in point. Properly made, even seemingly small amounts can yield joint health benefits equal to those found with modern drugs along with other benefits, such as for the cardiovascular system. But why depend on pills when you can brew bone broth yourself?

References:

1. http://www.townsendletter.com/FebMarch2005/broth0205.htm
2. Burton-Freeman B, Sesso HD. Whole food versus supplement: comparing the clinical evidence of tomato intake and lycopene supplementation on cardiovascular risk factors. Adv Nutr. 2014 Sep;5(5):457–85.
3. https://www.westonaprice.org/health-topics/why-broth-is-beautifulessential-roles-for-proline-glycine-and-gelatin/
4. Reginster JY, Dudler J, Blicharski T, Pavelka K. Pharmaceutical-grade Chondroitin sulfate is as effective as celecoxib and superior to placebo in symptomatic knee osteoarthritis: the ChONdroitin versus CElecoxib versus Placebo Trial (CONCEPT). Ann Rheum Dis. 2017 May 22. pii: annrheumdis-2016–210860. doi: 10.1136/annrheumdis-2016–210860. [Epub ahead of print]
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6. Martel-Pelletier J, Farran A, Montell E, et al. Discrepancies in composition and biological effects of different formulations of chondroitin sulfate. Molecules2015;20:4277–89.
7. Crolle G, D’Este E. Glucosamine sulphate for the management of arthrosis: a controlled clinical investigation. Curr Med Res Opin. 1980;7(2):104–9.