Bone: A Comprehensive Encyclopedic Reference
Identity and Nomenclature
As a dietary supplement category, bone encompasses a family of products derived from the skeletal tissue of vertebrate animals — primarily cattle (Bos taurus), pigs (Sus scrofa domesticus), poultry (Gallus gallus domesticus), and fish (various species). The term covers several distinct preparations that differ substantially in composition, processing method, and intended use:
- Bone broth — an aqueous extract produced by prolonged simmering of whole or sectioned animal bones, often with connective tissue, cartilage, and sometimes vinegar to facilitate mineral extraction; consumed as a liquid or concentrated into powders.
- Bone meal — a dry, finely ground powder produced by steam-cooking or calcining (heat-treating) raw animal bones, then milling; historically used as a calcium and phosphorus supplement.
- Microcrystalline hydroxyapatite concentrate (MCHC) — a processed, concentrated extract from whole bone that preserves the mineral-protein matrix in a microcrystalline form; marketed specifically for skeletal health.
- Demineralized bone matrix (DBM) — bone from which the inorganic mineral fraction has been removed, leaving behind the collagenous organic matrix and associated growth factors.
Animal bones have been exploited as a source of natural hydroxyapatite — the mineral that is the primary constituent of bones, calcified cartilage tissues, and teeth — and it finds large use in craniofacial, oral, maxillofacial, and orthopedic applications. Microcrystalline hydroxyapatite concentrate (MCHC) is a compound derived from whole bone, primarily containing calcium and phosphate in a crystalline structure similar to human bone, along with other bone matrix proteins and minerals.
The principal chemical components of bone-derived supplements vary by preparation but include: calcium hydroxyapatite [Ca₁₀(PO₄)₆(OH)₂], type I collagen and its hydrolysis products (gelatin and collagen peptides), glycosaminoglycans, and a broad range of trace minerals. Bone ash contains about 180 g phosphorus per kg dry matter, though the inclusion of varying amounts of organic matter in bone meal reduces this phosphorus content substantially depending on processing.
Natural Sources and Common Forms and Preparations
Bone meal is a slaughterhouse by-product of the meat industry, with the most common source being from cattle; however, it may also be made from hogs, sheep, chicken, or fish.
Bone broth is exactly what it sounds like — a broth or stock made by simmering animal bones — with a simmering time of around 12–48 hours, making it considerably longer to prepare than other stocks and broths.
Commercial preparations of bone-derived supplements are available in the following forms:
- Liquid bone broth — sold in cartons, cans, jars, or pouches, either plain or flavored; the most traditional form.
- Bone broth powder — a dehydrated, spray-dried or freeze-dried version, reconstituted in water; allows standardized dosing and longer shelf life.
- Bone meal tablets and capsules — compressed or encapsulated powder, used primarily as a calcium/phosphorus supplement.
- MCHC tablets and capsules — concentrated hydroxyapatite preparations, often combined with vitamin D and other co-factors.
- Collagen peptide powders derived from bone — partially hydrolyzed collagen extracted during broth-making or via enzymatic processing.
A study found that bone broth, both homemade and commercially produced, contained low levels (less than 5% of the RDA) of calcium and magnesium as well as heavy metals. The study noted that various factors can affect the amount of protein and minerals extracted in bone broth: the amount of acidity, cooking time, cooking temperature, and type of animal bone used.
Research has confirmed that reducing the broth pH from 8.38 to 5.32 significantly (p < 0.05) increases calcium and magnesium extraction by factors of 17.4 and 15.3, respectively. This is the scientific rationale behind the traditional practice of adding a small amount of vinegar or acidic wine to bone broth preparations.
Traditional and Historical Use
Ancient and Cross-Cultural Origins
The origins of bone broth can be traced back thousands of years. Early civilizations relied on slow-simmered broth to extract every possible nutrient from animal bones, whether hunters used every part of their catch or communities boiled bones for sustenance — a practice that ensured nothing went to waste.
Indigenous communities across the Americas also simmered bones over open fires to create nutrient-rich broths. Before there were even pots, ancient cultures used empty abdominal pouches from slaughtered animals to cook meat, bones, vegetables, and water with hot stones warmed in the fire.
Traditional Chinese Medicine
More than 2,500 years ago, in Chinese medicine, bone broth was used to strengthen the kidneys and support digestive health, and subsequently became a staple of traditional Asian meals, frequently used as the base for various Chinese, Korean, and Japanese soups. In Traditional Chinese Medicine (TCM), bone broth has been used for centuries to support kidney health, boost the immune system, and nourish the "Jing" — the essence that governs growth, development, and reproduction — with different animal bones used for specific health concerns, showcasing an early understanding of food as medicine.
Ayurvedic Tradition
In Indian Ayurveda, bone broth is believed to build "Ojas," the essence of life, and is recommended for those recovering from illness or childbirth.
European and Mediterranean Traditions
During the Middle Ages, bone broth (often called "stock") became a kitchen staple across Europe, valued not only for its nutritional properties but also as a way to stretch limited food resources. The French culinary tradition boasts a rich history of stocks and broths, known as bouillon and consommé, which form the base for countless classic dishes.
Chicken soup was termed "Jewish Penicillin" by the Egyptian physician and philosopher Moses Maimonides in the 12th century. In Europe and North America, bone broth has been used as a remedy for colds and flu, with chicken soup — a classic comfort food — being a direct descendant of this tradition.
African Traditions
In many African cultures, bone broth is a symbol of hospitality and is often served to guests as a welcoming gesture.
Historical Use of Bone Meal as a Supplement
Bone meal was the source of supplementary phosphorus used in the original South African studies of phosphorus deficiency (Theiler et al., 1924) and was greatly favored by graziers. Its use in human supplementation as a source of calcium and phosphorus has been documented throughout the 20th century, particularly before the advent of refined calcium salts.
Key Constituents and Active Compounds
Collagen, Gelatin, and Collagen-Derived Amino Acids
Collagen is the most abundant protein in the body; its braided, chain-like structure helps it strengthen a variety of tissues, including skin, bones, muscles, and tendons. Through slow cooking, bones release collagen, gelatin, calcium, magnesium, phosphorus, and amino acids such as glycine, proline, hydroxyproline, and cysteine.
Glycine, proline, and hydroxyproline contribute to 57% of total amino acids in collagen, which accounts for one-third of proteins in animals. As the most abundant protein in the body, collagen is essential to maintain the normal structure and strength of connective tissue, such as bones, skin, cartilage, and blood vessels.
While bone broth does contain collagen, the body breaks this down into amino acids, and there is no guarantee it will be used to rebuild skin or joints. Once ingested, collagen is hydrolyzed in the gastrointestinal tract into its constituent amino acids and short peptides, which then enter systemic circulation.
Calcium Hydroxyapatite
MCHC contains hydroxyapatite in a microcrystalline form, closely resembling the mineral structure found in human bone tissue, which is posited to enhance its bioavailability and absorption efficiency compared to other calcium supplements. Unlike conventional calcium supplements (such as calcium carbonate or calcium citrate), MCHC provides a complete nutritional bone support complex containing not only calcium but also phosphorus, collagen proteins, and organic factors such as glycosaminoglycans, all of which contribute to bone remodeling and regeneration.
Minerals
A comprehensive review of animal and human studies highlights that bone broth contains amino acids (glutamine, glycine, proline, histidine, arginine) and minerals (calcium, phosphorus, potassium, magnesium, zinc) that may be beneficial. Bone meal is primarily considered a phosphorus source, however it also contains nitrogen (1–4%), calcium (approximately 24%), and magnesium, with small amounts of other nutrients and trace minerals.
Growth Factors and Glycosaminoglycans in MCHC
MCHC products contain all the natural elements of healthy bone, including the essential minerals calcium and phosphorus, growth factors, type I collagen, glycosaminoglycans, and a broad range of other trace elements. Specialized analysis of MCHC preparations confirms the presence of 18 separate amino acids, including hydroxyproline and hydroxylysine, which are specific to collagen and especially important for collagen production.
Glycine and Glutamine: Mechanisms of Action
Glycine has documented anti-inflammatory properties and supports mucosal lining integrity, while glutamine is the primary fuel source for enterocytes — the cells lining the intestine. These properties form the primary mechanistic basis for the proposed gut-health effects of bone broth.
Scientific Evidence by Area of Use
Bone Mineral Density and Osteoporosis
The most clinically investigated bone-derived supplement for skeletal health is MCHC. Some scientific studies, mainly small clinical trials, have compared MCHC to other forms of calcium (such as calcium carbonate or citrate) and found that MCHC may help slow bone loss or improve bone mineral density in postmenopausal women and individuals at risk of osteoporosis.
A controlled clinical trial was carried out in 40 patients at risk of osteoporosis because of long-term treatment with prednisolone (5 to 20 mg/day) to determine the efficacy and tolerance of MCHC, where 32 patients were treated with 6 to 8 g MCHC for 12 months and 8 served as an untreated control group. In the MCHC-treated group, there was a dramatic and significant (p < 0.001) reduction in back pain during the trial, almost to the point of its disappearance; of 19 patients with initial back pain, only 2 still reported any pain at all after 12 months of MCHC treatment. Both mean cortical thickness and mean metacarpal index figures showed small, insignificant decreases during 12 months of MCHC treatment but much more marked decreases in the control group.
A separate controlled trial examined MCHC in 36 patients with chronic active hepatitis (CAH) on corticosteroid therapy over a period of 2 years. Continued reduction in bone mineral content of the radius (photon absorptiometry) was halted in those receiving MCHC, and iliac crest bone biopsy showed a non-significant increase in trabecular bone volume; the fall in iliac crest cortical plate thickness was significantly less (p < 0.025) in the MCHC group, with results overall consistent with a beneficial effect from MCHC in corticosteroid-induced osteoporosis.
Several clinical studies have examined MCHC's effects on bone health, with some suggesting a modest benefit in reducing bone loss compared to calcium carbonate or placebo; however, a few randomized controlled trials that found MCHC supplementation led to a slower rate of BMD loss in postmenopausal women are generally small, of short duration, and sometimes sponsored by supplement manufacturers, limiting the strength of the evidence.
While MCHC has a long history of use in Europe for bone health, most major guidelines for osteoporosis management prioritize well-studied interventions. The evidence base is limited, with relatively few well-controlled, large-scale human trials.
Regarding bone broth specifically as a source of bone-building nutrients: so far, there is no scientific evidence that bone broth can relieve joint pain, make skin firmer, improve digestion, or strengthen bone.
Gut Health and Intestinal Barrier Function
Researchers from the Mayo Clinic, including lead author Michael Camilleri, analyzed animal and human studies to explore how the nutritional components of bone broth affect the intestinal barrier, inflammation, and digestive disorders such as inflammatory bowel disease (IBD); their findings suggest that bone broth's composition of amino acids and minerals may actively promote gut healing and strengthen the intestinal lining.
Bone broth is rich in key amino acids such as glutamine, glycine, proline, histidine, and arginine, all of which have been shown to support cellular repair and maintain the integrity of the gut barrier; it also contains essential minerals including calcium, phosphorus, potassium, magnesium, and zinc. Together, these nutrients appear to reduce intestinal permeability and help regulate inflammation, particularly in individuals with IBD.
The authors caution that while preliminary evidence is promising, clinical trials are still needed to determine its efficacy as a therapeutic intervention. Human data remains limited and not definitive; there is no strong clinical evidence that bone broth alone can "heal" the gut, though it does contain nutrients that support tissue repair and overall digestive health.
A 2023 randomized crossover trial gave runners 10 g of collagen peptides daily for 7 days before intense exercise; separately, a 2024 glutamine meta-analysis analyzing 10 clinical trials found that glutamine supplementation did not significantly reduce intestinal permeability overall — though high doses (above 30 g/day) showed effects in short-term use. That is far more glutamine than would be obtained from a serving of bone broth.
Inflammation
Some studies suggest that bone broth can help reduce inflammation; chronic inflammation is associated with a host of conditions, including arthritis, Crohn's disease, and ulcerative colitis; the amino acids in bone broth may work to counteract inflammation-causing compounds in the body. However, this evidence is largely mechanistic or from animal models rather than rigorous human clinical trials.
A study published in Journal of Oral Facial Pain and Headache (2018) examined enriched chicken bone broth (ECBB) in a rat model of temporomandibular disorder. Based on findings that ECBB could reduce facial nocifensive behavior, this provides some evidence to support its potential use in the management of TMD; ECBB might also be expected to reduce pain-like behavioral responses associated with other diseases involving trigeminal nerve activation, including migraine, rhinosinusitis, trigeminal neuralgia, and orthodontic pain. This study was conducted entirely in an animal model, however, and does not constitute human clinical evidence.
Collagen and Skin Health
The claim that consuming collagen from bone broth will directly benefit human bones and joints is unfounded, as when humans consume collagen, it is broken down into individual amino acids, minerals, etc. These amino acids and minerals may then act like any other amino acid or mineral consumed; however, there is no evidence of an advantage to consuming amino acids and minerals from bone broth as opposed to from other foods.
The main finding of a key 2018/2019 study was that amino acid concentrations in bone broth made to a standardized recipe were significantly lower for hydroxyproline, glycine, and proline (p = 0.003) and hydroxylysine, leucine, and lysine (p = 0.004) than those provided by a potentially therapeutic dose (20 g) of reference collagen supplements. Non-standardized recipes, particularly those prepared in cafes, showed the highest levels of these amino acids, highlighting the inconsistency in bone broth preparations.
Protein and Satiety
Bone broth can be part of a healthy weight loss regime; it is loaded with protein — about 10 grams per serving — which can help a person feel full for longer. This extra protein can also assist in building lean muscle mass, which in turn enables the body to burn more calories throughout the day. These claims, however, reflect general nutritional properties of protein rather than outcomes from rigorous clinical trials of bone broth specifically.
Body Systems and Health Areas
Bone-derived supplements are used in association with the following body systems and health areas, based on their documented or proposed nutritional composition:
- Skeletal system: Calcium, phosphorus, and hydroxyapatite from bone meal and MCHC are associated with bone mineral density maintenance. MCHC has the strongest, though still limited, clinical evidence base in this area.
- Connective tissue / joints: Collagen, glycine, proline, and glycosaminoglycans from bone broth and MCHC are associated with cartilage and tendon support, though direct clinical evidence in humans specifically from bone preparations is limited.
- Gastrointestinal tract: This area has been investigated in a 2025 review in Digestive Diseases and Sciences, focusing on intestinal barrier integrity, intestinal permeability, inflammation, and inflammatory bowel disease.
- Skin: Collagen precursor amino acids from bone broth are associated with skin elasticity and hydration, though the clinical evidence is primarily from isolated collagen supplements rather than bone broth itself.
- Immune function: Glutamine, arginine, and zinc contribute to immune cell function, and TCM traditions reference immune support as a classical use of bone broth.
- Metabolism and electrolyte balance: The mineral content (potassium, magnesium, sodium) of bone broth is associated with electrolyte replenishment.
Dosage Forms and Reported Dosages
In a controlled clinical trial of MCHC for corticosteroid-induced osteoporosis, 32 patients were treated with 6 to 8 g MCHC per day for 12 months.
One formulation approach combining microcrystalline hydroxyapatite with vitamin D and ipriflavone used an effective amount of microcrystalline hydroxyapatite in the range of approximately 100 mg to 5,000 mg per daily serving.
In a study at Frontiers in Nutrition examining plasma amino acid concentrations, a 300 mL serve of bone broth was consumed by healthy, recreationally active males after an overnight fast, with blood samples drawn every 20 minutes for a total of 180 minutes; collagen proteins were found to be a superior source of glycine (683 ± 166 µmol/L) compared to dairy proteins (260 ± 65 µmol/L; p < 0.0001), while dairy proteins were a superior source of leucine.
A 2022 open-label study found that 20 g per day of collagen peptides (not whole bone broth) significantly reduced bloating and intestinal discomfort over 8 weeks in healthy women; however, the study had no placebo control, as participants knew what they were taking.
No standardized therapeutic dosage has been established by any major regulatory authority for bone broth as a supplement. Simmering times of 12–48 hours are typical in homemade preparations, with commercial products simmered for similar durations before concentration.
Safety Considerations and Interactions
Lead and Heavy Metal Contamination
This is the most extensively documented safety concern for bone-derived supplements and is grounded in peer-reviewed literature. There are concerns about the high sodium levels in commercial broths and the potential for toxic heavy metals, such as lead, to leach from the bones during the long simmering process.
The heat utilized when producing bone broth has been shown to mobilize sequestered lead compounds from poultry bones, greatly increasing the concentration of lead present in the bone broth water (Monro et al., 2013).
One small study found that bone broth made from chicken bones contained three times the lead as chicken broth made with the meat only; however, the amount of lead in the bone broth per serving was still less than half the amount permitted by the Environmental Protection Agency in drinking water.
For bone meal supplements specifically, lead contamination is not restricted to bone meal and dolomite; significant amounts of lead, and also aluminum, have been found in calcium carbonate supplements labeled "oyster shell" or "natural source." While no evidence for in vivo toxicity has emerged, chronic use of these supplements may constitute unnecessary metal exposure.
Products containing different calcium forms (dolomite, bone meal, natural carbonate) have historically had higher lead levels than others (refined carbonate, lactate, gluconate, acetate), but the gap has closed considerably since the year 2000.
University of Florida researchers noted that the levels of lead in calcium supplements are very small and would only potentially be a problem after many years; they noted that when taken in normal daily dose ranges — 800 milligrams for children or 1,500 milligrams for women trying to prevent bone loss — the supplements would fall below the 6 microgram total daily exposure limit suggested by many experts. However, people with failing kidneys who are directed to consume many times the normal dose of calcium could find themselves taking in as much as 20 micrograms of lead daily.
Histamine Content
Histidine is a precursor to histamine and is a major amino acid found in bone broth. Approximately 1% of the population has a histamine intolerance; the extended cooking time in bone broth increases histamine production and can trigger allergy symptoms. Histidine, an amino acid found in animal flesh, can be converted into histamine by bacteria that possess the enzyme histidine decarboxylase; histamine levels in meat can vary based on processing and freshness, with beef tending to exhibit higher histamine levels because it undergoes an extended storage process before being sold.
Sodium Content
There are concerns about the high sodium levels in commercial broths. Commercial bone broth preparations, particularly flavored or salted varieties, can be significant sources of dietary sodium, which is a relevant consideration for individuals managing hypertension or cardiovascular risk.
Variability in Nutrient Composition
Nutrient levels (such as protein and minerals) vary significantly depending on the bones used and the length of time they are simmered. The duration of hydrothermal treatment during the preparation of bone broth also affects its protein content. This means that nutritional labeling of bone broth products may not reliably reflect what is actually consumed, and the therapeutic doses used in research on isolated collagen and amino acids are often not achievable through bone broth alone.
Overall Evidence Strength Assessment
Despite its popularity and the numerous claims of its medicinal properties, there is very little scientific research regarding bone broth specifically. The literature is light on studies looking at bone broth or even broth and soups in general, which makes it difficult to confirm or argue against proposed benefits since there are limited studies confirming the benefits or proving the hypotheses wrong. The strongest clinical evidence base for any bone-derived supplement is for MCHC in the context of corticosteroid-induced bone loss, where a small number of controlled trials have shown signals of benefit; however, even this evidence base consists primarily of small trials, some uncontrolled, with acknowledged limitations. Evidence for bone broth in gut health, joint support, skin health, and immune function remains either mechanistic, animal-model-based, or derived from studies of isolated constituent compounds (collagen peptides, glutamine) rather than whole bone broth itself.
References
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