Do not expect extra calcium or bone broth to make a fracture heal faster

It costs nothing and saves the money and effort spent on calcium tablets, vitamin D, and making broth every day. Supplement a deficiency if testing identifies one; otherwise, do not take extra supplements.

Start with vitamin D. A 2023 systematic review included 14 studies involving 2,734 fracture patients. The authors concluded that vitamin D alone had little effect on bone healing, whether the fracture united, or function after recovery. Studies reporting benefits generally had lower quality. The authors stated that when only randomized trials were considered, none showed a benefit from supplementation. One trial enrolled 100 people with long-bone fractures and low vitamin D. Half received a single dose of 100,000 IU within two weeks of injury; half received a placebo. Two people in each group had nonunion, or 4% overall. Another trial enrolled 102 people aged 18 to 50 with femoral or tibial fractures, assigning them to four groups receiving different doses or placebo. Healing scores showed no differences at 3 or 12 months. Another study enrolled 32 postmenopausal women with wrist fractures. Compared with no supplementation, the high-dose group receiving the equivalent of 1,800 IU daily had lower bone resistance to compression. Now consider calcium. A 2014 systematic review found few clinical studies on how vitamin D deficiency or supplementation affects fracture healing, with inconclusive results. The two studies it found combined calcium and vitamin D; they measured increased bone density or callus—newly formed bone—at the fracture site, rather than how quickly the fracture healed. Finally, bone broth: a study in Kaohsiung, Taiwan, tested three kinds of noodle dishes with bone broth, each containing 450 to 550 grams of broth. Average calcium content was 14 to 39 milligrams per serving, or 1.4% to 3.9% of the recommended daily 1,000 milligrams. The authors concluded that one serving provided less than 5% of the daily recommendation. China recommends 800 milligrams daily for ages 18 to 49 and 1,000 milligrams for people aged 50 and older, with an upper limit of 2,000 milligrams daily. That standard states that long-term excessive calcium intake increases kidney stone risk. A U.S. trial enrolled 36,282 postmenopausal women, giving them 1,000 milligrams of calcium plus 400 IU of vitamin D daily and following them for an average of 7 years. Kidney stone risk was about 17% higher (HR 1.17, 95% CI 1.02–1.34, the confidence interval). Hip fractures were about 12% less frequent, but the difference was not statistically significant (HR 0.88, 0.72–1.08). The approach seems good value because of the intuition that bones are made of calcium, so eating more calcium should make them heal faster.

Gatt T, Grech A, Arshad H (2023). The Effect of Vitamin D Supplementation for Bone Healing in Fracture Patients: A Systematic Review. Advances in Orthopedics, 2023, 6236045. https://doi.org/10.1155/2023/6236045；Haines N, Kempton LB, Seymour RB, et al. (2017). The effect of a single early high-dose vitamin D supplement on fracture union in patients with hypovitaminosis D: a prospective randomised trial. Bone & Joint Journal, 99-B(11), 1520-1525. https://doi.org/10.1302/0301-620X.99B11.BJJ-2017-0271.R1；Slobogean GP, Bzovsky S, O'Hara NN, et al. (2023). Effect of Vitamin D3 Supplementation on Acute Fracture Healing: A Phase II Screening Randomized Double-Blind Controlled Trial. JBMR Plus, 7, e10705. https://doi.org/10.1002/jbm4.10705；Heyer FL, de Jong JJ, Willems PC, et al. (2021). The Effect of Bolus Vitamin D3 Supplementation on Distal Radius Fracture Healing: A Randomized Controlled Trial Using HR-pQCT. Journal of Bone and Mineral Research, 36, 1492-1501. https://doi.org/10.1002/jbmr.4311；Gorter EA, Hamdy NA, Appelman-Dijkstra NM, Schipper IB (2014). The role of vitamin D in human fracture healing: a systematic review of the literature. Bone, 64, 288-297. https://doi.org/10.1016/j.bone.2014.04.026；Hsu DJ, Lee CW, Tsai WC, Chien YC (2017). Essential and toxic metals in animal bone broths. Food & Nutrition Research, 61, 1347478（表 2、表 3）. https://doi.org/10.1080/16546628.2017.1347478；国家卫生和计划生育委员会 (2018). WS/T 578.2—2018 中国居民膳食营养素参考摄入量 第 2 部分：常量元素（表 1；定义 3.7）. https://www.nhc.gov.cn/wjw/yingyang/201805/f2c614be95fe41dba8123c23a6e6fb55/files/1739783539207_73894.pdf；Jackson RD, LaCroix AZ, Gass M, et al. (2006). Calcium plus vitamin D supplementation and the risk of fractures. New England Journal of Medicine, 354(7), 669-683. https://doi.org/10.1056/NEJMoa055218；Doetsch AM, Faber J, Lynnerup N, et al. (2004). The effect of calcium and vitamin D3 supplementation on the healing of the proximal humerus fracture: a randomized placebo-controlled study. Calcified Tissue International, 75, 183-188. https://doi.org/10.1007/s00223-004-0167-0（备注里那项）；Gorter EA, Krijnen P, Schipper IB (2017). Vitamin D status and adult fracture healing. Journal of Clinical Orthopaedics and Trauma, 8(1), 34-37. https://doi.org/10.1016/j.jcot.2016.09.003（备注里那项）

Points of uncertainty: there are two small signals of possible benefit. A Danish trial enrolled 30 older women with fractures of the upper arm near the shoulder who had osteoporosis or low bone mass. Those receiving 800 IU of vitamin D plus 1 gram of calcium daily had higher bone density at the fracture site at week 6 (0.623 versus 0.570 g/cm²). But it measured only bone density, not whether the bone had healed, and had too few participants. A post hoc analysis of the 102-person trial found slightly better functional scores with high-dose vitamin D; the authors said further trials were needed to confirm this. Existing vitamin D deficiency is a separate case. A Dutch observational study found delayed healing in 9.7% of people who remained deficient after supplementation, compared with 0.3% of those who were not deficient initially and 1.7% of those whose deficiency was corrected. This was observational and cannot establish causation. If testing finds a deficiency, follow your doctor’s advice to restore normal levels. People with diagnosed osteoporosis or a fracture after a minor fall need osteoporosis medication; see section 1, item 40 (osteoporosis medication). Calcium tablets cannot replace it. Long-term supplementation offers no benefit for people without vitamin D deficiency; see item 3 in this section (vitamin D supplements). The point is to avoid excessive extra supplementation, not to eat less calcium. Keep getting enough calcium in your meals; see item 21 in this section (cutting out calcium to prevent kidney stones). For what to do after a fall when a fracture is suspected, see section 13, item 41 (suspected fracture). The benefit rating is medium, based on a year’s spending on calcium tablets and vitamin D. You are the person who benefits.