If you’ve been diagnosed with osteopenia or osteoporosis, your doctor has already discussed calcium, vitamin D, and weight-bearing exercise with you. That’s good advice, but there’s more to it than just those three things.
There’s another nutrient that deserves a seat at the table. Probably think of more for fighting colds and the flu than for helping with bones. It’s vitamin C.
There’s a growing body of human research that suggests vitamin C plays a much bigger role in bone health than most people realize. Dr. Tom Levy, in his book Death by Calcium, discusses how vitamin C also supports bone health. But that book was published back in 2013, and there’s more research since then that verifies what he already found. Vitamin C is a powerful teammate that helps all the nutrients together build healthy bones for you. Here’s what the science shows and what you can do about it today.
Your Bones Are More Than Just Minerals
Most of us picture bones as very mineral-dense structures like sticks of calcium. But that’s not the full picture. Bones are roughly 50% protein by volume. The primary protein is type 1 collagen. It’s the collagen that forms the flexible scaffold on which mineral is built. This scaffolding gives bones their strength and slight flexibility, they need to absorb impact without snapping, like a brittle piece of chalk.
The calcium and other minerals fill in around the scaffold, which provides bones with their hardness and density. On a side note, vitamin K2 cross-links another protein, osteocalcin, which makes the protein scaffold even stronger. So vitamin K2 is also a key player. But back to vitamin C.
Without healthy collagen, the minerals don’t have anything to anchor onto. You can take all the calcium you want, but if your protein structure is not there, your bones will be brittle and prone to fracture. And the number one requirement for building collagen is vitamin C.
How Vitamin C Builds and Protects Your Bones
Vitamin C supports bone health through at least four distinct pathways, each backed by human cell research and clinical evidence.
It builds the collagen scaffold.
Vitamin C is essential for the hydroxylation of proline and lysine — two amino acids that stabilize collagen fibers. Without enough vitamin C, collagen is structurally weak. This is why severe vitamin C deficiency (scurvy) has been associated with bone and joint problems for centuries. Studies with human osteoblast cells confirm that vitamin C directly stimulates type I and type III collagen synthesis in bone tissue (Malmir et al., British Journal of Nutrition, 2018).
It activates bone-building cells.
Vitamin C promotes the differentiation and activity of osteoblasts — the specialized cells responsible for forming new bone. It enhances the expression of key bone-building markers, including alkaline phosphatase and osteocalcin. Equally important, vitamin C deficiency does the opposite: it impairs osteoblast function while simultaneously stimulating osteoclasts, the cells that break bone down. That’s a double hit (Aghajanian et al., Journal of Bone and Mineral Research, 2015).
It helps protect bone cells from oxidative damage.
After menopause, declining estrogen exposes bone cells to increased oxidative stress. Vitamin C neutralizes the free radicals that damage those cells — a protective role that works independently of its collagen-building function.
It flips genetic switches for bone formation.
Perhaps the most exciting recent discovery came from a 2022 study published in Nature Communications. Researchers found that vitamin C doesn’t just help assemble collagen — it epigenetically controls the genetic switches that activate bone-building genes. The study showed that bone cell differentiation is “strictly and continuously dependent on vitamin C,” indicating that this nutrient is involved at a more fundamental level than previously understood (Khani et al., Nature Communications, 2022).
What the Human Research Shows For Vitamin C and Bones
The research on the mechanisms of how vitamin C helps bones is great, but we want to know: does it translate into real outcomes in real people? So here’s what the strongest human evidence also tells us.
The Framingham Osteoporosis Study — one of the most respected long-term epidemiological programs in the world — tracked 958 men and women (mean age 75) over 17 years. Participants with the highest total vitamin C intake had significantly fewer hip fractures and non-vertebral fractures compared to those with the lowest intake. The difference in the vitamin C intake was actually due to supplements, not dietary intake, in this population. An earlier analysis from the same cohort found that higher vitamin C intake was associated with significantly less bone loss over four years (Sahni et al., Osteoporosis International, 2009; Sahni et al., Journal of Nutrition, 2008).
Two major meta-analyses have pooled data from multiple observational studies to assess the overall picture. A 2019 analysis in Frontiers in Endocrinology combined 13 studies and found that people with the highest dietary vitamin C intake had a 34% lower risk of hip fracture compared to those with the lowest intake (Sun et al., 2019). A 2018 analysis in the British Journal of Nutrition found that higher vitamin C intake was associated with a 33% lower risk of osteoporosis overall and positively correlated with bone mineral density at the femoral neck and lumbar spine — two of the most critical fracture sites (Malmir et al., 2018). Together, these two meta-analyses found a similar decrease in the risk of hip fracture or osteoporosis.
Studies focused specifically on postmenopausal women consistently show the same pattern. Women with higher vitamin C intake (137–176 mg/day) had significantly lower osteoporosis risk compared to those consuming 91 mg/day or less. Women diagnosed with osteoporosis had markedly lower vitamin C levels in blood than healthy controls — 5.28 versus 9.77 mg/L (Brzezińska et al., Nutrients, 2020). Data from the Boston Puerto Rican Health Study confirmed that postmenopausal women with sufficient plasma vitamin C had significantly higher hip bone density than those with low plasma vitamin C levels (Mangano et al., Journal of Nutrition, 2021).
A small but notable randomized trial found that postmenopausal women who received just 250 mg/day of vitamin C in addition to their standard osteoporosis treatment showed significantly greater bone mineral density after 1 year than those on standard treatment alone. That isn’t even very much vitamin C, but it was enough to make a difference. The researchers concluded it was “a safe and low-cost addition to standard treatment” (Biomedical and Pharmacology Journal, 2014).
One important nuance: a 2024 study using Mendelian randomization — a genetic method for testing causality — did not find a direct genetic causal link between vitamin C levels and osteoporosis risk (Liu et al., Hereditas, 2024). This doesn’t mean vitamin C is unhelpful, but it does suggest the relationship is complex. Vitamin C likely works best as part of a comprehensive nutritional approach, as a team member, not as the star quarterback.
The Bone Health Team: Vitamin C’s Place in the Lineup
Supplemental vitamin C, in addition to what you get from your fruits and vegetables, appears to be helpful based on the evidence above. Bone health is a team effort.
You need calcium for the building blocks. You need magnesium to balance calcium. Vitamin D helps calcium get absorbed to the right places. Vitamin K2 directs the calcium to the right places—to the bones and not to soft tissues like cartilage and the walls of your arteries.
Weight-bearing exercise stimulates bone remodeling and strengthens bones. Vitamin C builds the collagen scaffold that holds things together. It also activates the cells that form new bone and protects them from oxidative damage. A whole-foods plant-based diet with a little extra vitamin C is great for bones, as the nutrients work synergistically. A vitamin D3 / K2 supplement is also important.
Practical Steps You Can Take Today
The Hallelujah Diet emphasizes a high intake of fresh, raw fruits and vegetables, as well as vegetable juice. This will provide you easily with 200-300 milligrams of vitamin C a day just from your foods.
In addition, 1,000 milligrams of vitamin C in supplement form, such as liposomal vitamin C or sodium ascorbate, is a great idea and will help bones. Most animals make their own vitamin C, and there are many reasons why a higher intake of vitamin C is beneficial, as I’ve written about previously.
The Bottom Line
It would be nice to have more large-scale randomized controlled trials, but we now have enough evidence to act, from long-term population studies, small trials, analyses of multiple studies, and mechanistic studies that show how vitamin C works.
Vitamin C is cheap and is widely available. You should take more vitamin C for many reasons, including stronger bones.
If your DEXA scores have you concerned, don’t think you’re doing all you can by just taking calcium and vitamin D. You can do a lot more to control your own health.
Adopt the Hallelujah Diet and eat a large salad every day. Stay active with weight-bearing exercise and take extra vitamin C. Use a holistic nutritional approach to fully support your body, including your skeleton.
References
- Sahni S, et al. (2009). “Protective effect of total and supplemental vitamin C intake on the risk of hip fracture — a 17-year follow-up from the Framingham Osteoporosis Study.” Osteoporosis International, 20(11):1853–1861. PubMed
- Sahni S, et al. (2008). “High vitamin C intake is associated with lower 4-year bone loss in elderly men.” Journal of Nutrition, 138(10):1931–1938. PubMed
- Zeng LF, et al. (2019). “Can Dietary Intake of Vitamin C-Oriented Foods Reduce the Risk of Osteoporosis, Fracture, and BMD Loss? Systematic Review With Meta-Analyses of Recent Studies.” Frontiers in Endocrinology, 10:844. PubMed
- Malmir H, Shab-Bidar S, Djafarian K. (2018). “Vitamin C intake in relation to bone mineral density and risk of hip fracture and osteoporosis: a systematic review and meta-analysis of observational studies.” British Journal of Nutrition, 119(8):847–858. PubMed
- Brzezińska O, et al. (2020). “Role of Vitamin C in Osteoporosis Development and Treatment — A Literature Review.” Nutrients, 12(8):2394. PubMed
- Liu Z, et al. (2024). “Serum vitamin C levels and risk of osteoporosis: results from a cross-sectional study and Mendelian randomization analysis.” Hereditas, 161:43. PubMed
- Thaler R, Khani F, et al. (2022). “Vitamin C epigenetically controls osteogenesis and bone mineralization.” Nature Communications, 13:5883. PubMed
- Aghajanian P, et al. (2015). “The Roles and Mechanisms of Actions of Vitamin C in Bone: New Developments.” Journal of Bone and Mineral Research, 30:1945–1955. PubMed
- Morton DJ, Barrett-Connor EL, Schneider DL. (2001). “Vitamin C Supplement Use and Bone Mineral Density in Postmenopausal Women.” Journal of Bone and Mineral Research, 16(1):135–140. PubMed
- Zhang R, et al. (2023). “Association between multiple vitamins and bone mineral density in older adults.” BMC Musculoskeletal Disorders, 24:113. PubMed
- Mangano KM, et al. (2021). “Sufficient Plasma Vitamin C Is Related to Greater Bone Mineral Density among Postmenopausal Women from the Boston Puerto Rican Health Study.” Journal of Nutrition, 151(12):3764–3772. PubMed
- Pande V, Choubey J. (2014). “Does Administration of Vitamin C Improve Osteoporosis in Post-Menopausal Women.” Biomedical and Pharmacology Journal, 7(2).DOI
