An evidence-based review of bone broth and health.
Since the Paleo and Primal diet booms of the 2000s and the resurgence of interest in real food-based lower-carbohydrate nutrition of recent years, bone broth has become an incredibly popular food and supplement for athletes and laypeople alike.
What’s bone broth?
Bone broth is a traditional food prized by people throughout the world and throughout history for its nutritive and restorative effects. A type of stock, broths are made by boiling or simmering bones, skin, and other tissue, along with vegetables, herbs, spices or other flavourings, for long periods of time (typically 30 mins, up to several days in some cases) and often with the addition of an acid like vinegar to aid extraction of nutrients, although cooking time has the greatest effect on extracting these nutrients. (1) Broth provided, throughout history, a way for people to store a nutrient-dense food for longer periods of time than fresh meat, and allowed the extraction of nutrients, particularly amino acids from foods that would otherwise be food waste and broths can be used on their own as a meal, snack or drink, or as a base for soups, sauces, or as a stock for cooking other foods.
What does the research say?
There is little research on bone broth at this time. The few studies performed have mostly been on animal subjects and have yielded promising results in rabbits for improved bone healing, (2) and in an interesting study in rats, an enriched bone broth formula given at the time of weaning was able to reduce odour triggered migraine pain! (3) (The weird world of research!)
The main benefits for bone broth come from the nutrients extracted during reduction. These are mainly amino acids from proteins, particularly collagen peptides incorporating the amino acids glycine, hydroxyproline, proline, and alanine, which bone broth provides, albeit in lower amounts than standardised collagen hydrolysates, (1) along with small amounts of minerals like calcium, magnesium, sodium, potassium, iron and some essential fatty acids. These peptides from collagen protein are beginning to be studied quite extensively. They have been shown to enter the bloodstream and reach tissue (like skin and joints) as a result of taking a collagen supplement. (4-7) Approximately one cup of bone broth supplies the same amount of beneficial amino acids and peptides as a 10 g dose of a refined collagen supplement. (1) Research shows that collagen has anti-aging, anti-inflammatory, antioxidant, and joint-supporting properties. (8, 9) Specifically, collagen has been shown to improve skin elasticity and hydration for improved skin health, at doses equivalent to the amount contained in ¼-1 cup of bone broth. (10, 11) Even smaller amounts (around 1200 mg of collagen, or 2 Tbsp of broth) might improve joint pain with longer-term, consistent use, based on the existing collagen research, (12) while higher doses of ~10 g (~1 cup of broth) taken daily, might improve joint mobility and reduce pain and inflammation. (13-15)
It’s important to remember that not all broths are created equal. Bones, marrow and connective tissue can store heavy metals like lead. A study on three different types of organic chicken broth showed levels of lead in the resulting broth can be around 8-11x higher (7.01-9.5 mcg/L) than the water used as the base of the broth. (16)
Bone broth is a reliable source of beneficial nutrients, including the collagen-derived amino acids and peptides (albeit in lower doses than that provided by a collagen hydrolysate) that have demonstrated benefits for a range of outcomes like pain, mobility, and reductions in inflammation.
1. Alcock RD, Shaw GC, Burke LM. Bone Broth Unlikely to Provide Reliable Concentrations of Collagen Precursors Compared With Supplemental Sources of Collagen Used in Collagen Research.29(3):265.
2. Aljumaily MA. The effect of concentrated bone broth as a dietary supplementation on bone healing in rabbits. Annals of the College of Medicine Mosul. 2011;37(1&2):42-7.
3. Peterson O. Dietary Inclusion of Enriched Chicken Bone Broth Prevents Trigeminal Sensitization Meditated by Early Life Stress. 2018.
4. Shigemura Y, Kubomura D, Sato Y, Sato K. Dose-dependent changes in the levels of free and peptide forms of hydroxyproline in human plasma after collagen hydrolysate ingestion. Food Chemistry. 2014;159:328-32.
5. Sugihara F, Inoue N, Kuwamori M, Taniguchi M. Quantification of hydroxyprolyl-glycine (Hyp-Gly) in human blood after ingestion of collagen hydrolysate. Journal of Bioscience and Bioengineering. 2012;113(2):202-3.
6. Yazaki M, Ito Y, Yamada M, Goulas S, Teramoto S, Nakaya M-a, et al. Oral Ingestion of Collagen Hydrolysate Leads to the Transportation of Highly Concentrated Gly-Pro-Hyp and Its Hydrolyzed Form of Pro-Hyp into the Bloodstream and Skin. Journal of Agricultural and Food Chemistry. 2017;65(11):2315-22.
7. Bello AE, Oesser S. Collagen hydrolysate for the treatment of osteoarthritis and other joint disorders:a review of the literature. Current Medical Research and Opinion. 2006;22(11):2221-32.
8. Song H, Li B. Beneficial effects of collagen hydrolysate: a review on recent developments. Biomed J Sci Technol Res. 2017:1-4.
9. Moskowitz RW. Role of collagen hydrolysate in bone and joint disease. Seminars in Arthritis and Rheumatism. 2000;30(2):87-99.
10. Sugihara F. Clinical Effects of Ingesting Collagen Hydrolysate on Facial Skin Properties―A Randomized, Placebo—controlled, Double—blind Trial―. 薬理と治療. 2015;43(1):67-70.
11. Ohara H, Ito K, Iida H, Matsumoto H. Improvement in the moisture content of the stratum corneum following 4 weeks of collagen hydrolysate ingestion. Nippon Shokuhin Kagaku Kogaku Kaishi = Journal of the Japanese Society for Food Science and Technology. 2009;56(3):137-45.
12. Bruyère O, Zegels B, Leonori L, Rabenda V, Janssen A, Bourges C, et al. Effect of collagen hydrolysate in articular pain: A 6-month randomized, double-blind, placebo controlled study. Complementary Therapies in Medicine. 2012;20(3):124-30.
13. Zuckley L, Angelopoulou KM, Carpenter MR, McCarthy S, Meredith BA, Kline G, et al. Collagen hydrolysate improves joint function in adults with mild symptoms of osteoarthritis of the knee. Medicine & Science in Sports & Exercise. 2004;36(5):S153-S4.
14. Benito-Ruiz P, Camacho-Zambrano MM, Carrillo-Arcentales JN, Mestanza-Peralta MA, Vallejo-Flores CA, Vargas-López SV, et al. A randomized controlled trial on the efficacy and safety of a food ingredient, collagen hydrolysate, for improving joint comfort. International journal of food sciences and nutrition. 2009;60(sup2):99-113.
15. Clark KL, Sebastianelli W, Flechsenhar KR, Aukermann DF, Meza F, Millard RL, et al. 24-Week study on the use of collagen hydrolysate as a dietary supplement in athletes with activity-related joint pain. Current Medical Research and Opinion. 2008;24(5):1485-96.
16. Monro JA, Leon R, Puri BK. The risk of lead contamination in bone broth diets. Medical Hypotheses. 2013;80(4):389-90.