In a recent conversation with Dr. Carolyn Dean, medical doctor, naturopath, and leading magnesium expert, I discovered the important relationship between magnesium and bone health. Dr. Dean, who has authored over 35 books including The Magnesium Miracle, revealed insights that challenge conventional thinking about magnesium, osteoporosis, osteopenia, and bone density.
Summary: Magnesium for Bone Health
For decades, bone health advice has focused almost exclusively on protein, vitamin K, calcium and vitamin D, but this overlooks a critical piece of the puzzle. In this post, I cover a conversation with magnesium expert Dr. Carolyn Dean, as well as the latest research on magnesium and bone health.
The post covers the following:
- Why magnesium, which makes up 60% of the mineral content in your bones, deserves more attention.
- How a deficiency in magnesium harms your bones and could cause osteopenia and eventually osteoporosis.
- The role magnesium can play in improving bone health. Magnesium builds the collagen scaffolding that calcium bonds to, stimulates bone-building cells (osteoblasts), and prevents excessive bone breakdown.
- How combining calcium with magnesium may produce better bone density results than calcium alone, yet modern diets often create an imbalance with far more calcium than magnesium.
- The best type of magnesium for your bones.
- How much magnesium to take for osteoporosis and osteopenia.
- Who should not take magnesium.
If you’re concerned about osteoporosis or osteopenia, understanding magnesium’s foundational role in bone health could be the missing link in your prevention strategy.
Is Magnesium Good for Your Bones?
Yes, and the reason is structural rather than incidental.
Approximately 60% of the magnesium in your body is located in your bones. (1) Yet when healthcare providers discuss bone composition, they typically focus almost exclusively on calcium and phosphorus, with magnesium barely getting a mention. Magnesium is essential for bone development, mineralization, bone remodeling, and the function of bone cells (osteoblasts and osteoclasts).
Bones are living tissue with a sophisticated architecture. They contain a soft, flexible matrix made of collagen and connective tissue, and this is where magnesium does its work:
- Building the foundation: Magnesium helps produce and manufacture collagen, which creates the soft matrix onto which calcium bonds. This scaffolding holds everything together. Without this foundation, calcium has nowhere to properly deposit.
- Stimulating bone growth: Research shows that magnesium ions significantly increase osteoblast activity. Osteoblasts are the cells that build new bone. Studies have demonstrated that magnesium induces significant increases in cell viability, alkaline phosphatase activity, and osteocalcin levels of human osteoblasts, and these effects are positively associated with both the concentration of magnesium and the length of exposure. (2)
- Preventing bone loss: Magnesium deficiency results in increased formation of osteoclasts during bone remodeling, the cells that break down bone. (3,4) Less magnesium means less bone building and more bone breaking.
Observational studies (6) indicate that lower magnesium intake correlates with reduced bone mineral density, particularly at the hip and femoral neck, and that lower bone density is associated with increased fracture risk.
How Magnesium Deficiency Leads to Osteopenia and Osteoporosis
Magnesium deficiency promotes osteopenia and osteoporosis through two main pathways:
- Parathyroid Hormone (PTH) Pathway
- Vitamin D Pathway
1. Parathyroid Hormone (PTH) Pathway:
A magnesium deficiency disrupts the secretion of Parathyroid Hormone (PTH) and can potentially lead to PTH resistance. PTH regulates calcium and phosphorus metabolism, maintains the proper levels of calcium in the blood, stimulates vitamin D production in the kidneys, and affects the bone remodeling process.
The PTH imbalance caused by magnesium deficiency affects bone remodeling by altering the ratio of RANK ligand (RANKL) to osteoprotegerin (OPG). When these two proteins are in balance, bone formation is equal to bone resorption. When the RANKL/OPG ratio is imbalanced, this leads to increased osteoclast formation, elevated bone resorption, and eventually osteopenia or osteoporosis.
2. Vitamin D Pathway:
A magnesium deficiency impairs the synthesis and metabolism of vitamin D. Low vitamin D levels affect calcium absorption which, like the PTH imbalance described above, disrupts the balance between bone formation and breakdown. Read my post on vitamin D and bone health to learn more about vitamin D and osteoporosis.
Magnesium and Osteoporosis
When asked if magnesium will improve bone density and whether it is good for osteoporosis, Dr. Dean’s response focuses on the fundamental architecture of bone:
Magnesium helps the production of that soft tissue matrix, which takes up 30 to 40% of your bone. The magnesium is important for building the scaffolding onto which the calcium will deposit. Without this scaffolding, you can’t build strong bones, no matter how much calcium you take.
Research supports this foundational role. In a 1990 study of postmenopausal women on hormone therapy, a dietary program emphasizing magnesium over calcium (500 mg of calcium with 200 mg of magnesium) produced an 11% increase in heel bone density over nine months, compared to 0.7% in women who received dietary advice alone. (5) The study is small and old and measured the heel rather than the hip or spine, but it points in the same direction as the larger observational evidence.
As we age, our bones naturally lose hydration and flexibility. That soft tissue matrix collapses and dehydrates, leaving behind brittle calcium carbonate. Maintaining adequate magnesium, along with vitamin C (which helps produce collagen) and other nutrients such as vitamin K2 and vitamin D, helps preserve that flexibility and resilience.
Magnesium for Osteopenia and Bone Loss
Osteopenia is the stage where bone loss has begun but has not yet reached the threshold for osteoporosis. It is the point at which changes to nutrition and exercise have the most leverage.
Magnesium supports the bone-building process that osteopenia disrupts, and correcting a deficiency removes one of the drivers of continued bone loss. Both pathways described above, parathyroid hormone and vitamin D, are already at work at this stage.
Magnesium alone will not reverse osteopenia. It works alongside progressive resistance exercise, adequate calcium, vitamin D, and sufficient protein. What magnesium does is make sure the scaffolding is there for the rest to build on.
Best Magnesium for Bones: Citrate, Glycinate, or Oxide?
The short answer: citrate has the most direct bone research. Glycinate is gentler on your stomach. Both are absorbed far better than oxide. The most important factor is taking an adequate dose consistently, whichever form you choose.
Intervention studies on magnesium and bone health have used citrate, carbonate, and oxide forms, and all showed benefits for both bone mineral density and fracture risk. (7) But absorption differs sharply between them:
Magnesium citrate vs. oxide:
Magnesium citrate is significantly more soluble and bioavailable than magnesium oxide, with urinary magnesium excretion after citrate being substantially higher than after oxide.
Magnesium citrate vs. glycinate:
A randomized, double-blind study found that magnesium citrate showed superior bioavailability after 60 days compared to magnesium oxide and amino-acid chelate, with citrate leading to the greatest mean serum magnesium concentration.
No study has directly compared glycinate against citrate for bone outcomes specifically. What we can say:
- All three forms have shown bone benefit in research.
- Citrate and glycinate are both better absorbed than oxide.
- Citrate has the most evidence specifically for bone health.
- Glycinate is gentler on the digestive system and less likely to cause loose stools.
- Oxide is the least expensive and the most poorly absorbed, but it has still shown bone benefit when combined with calcium.
Practical recommendation:
Choose citrate if you want the form with the most bone research and you don’t mind a mild laxative effect. Choose glycinate if you have a sensitive stomach. Either is a good choice. Consistency matters more than the label.
Magnesium Type Comparison
All types of magnesium shown here have demonstrated bone health benefits in research studies. Choose based on your priorities: citrate for maximum evidence, glycinate for sensitive stomachs, or oxide/carbonate for budget-friendly options. Discuss these options with a Registered Nutritionist.
Magnesium Type for Bone Health Rating System
- Bone Health Research Evidence: Evidence from clinical studies of bone density and fracture.
- Bioavailability: How well the body absorbs and uses magnesium.
- Digestive Tolerance: How gentle the magnesium type is on your stomach and intestines.
How to Read a Magnesium Label
Magnesium supplements are compounds. Magnesium is bonded to something else, and the number on the front of the bottle is often the weight of the whole compound, not the magnesium inside it.
This matters more than most people realize:
- 500 mg of magnesium oxide contains about 300 mg of elemental magnesium.
- 500 mg of magnesium citrate contains about 80 mg.
- 500 mg of magnesium glycinate contains about 70 mg.
Same number on the front. Very different amounts of magnesium.
Every dosage figure on this page refers to elemental magnesium. You will find it on the Supplement Facts panel, not on the front of the bottle.
This also explains a number that confuses people in the research. One study gave postmenopausal women with osteoporosis 1,830 mg of magnesium citrate daily for 30 days and found improvements in their bone turnover markers. (7) That sounds like an enormous dose. It is not. 1,830 mg of magnesium citrate contains about 290 mg of elemental magnesium.
How Much Magnesium for Osteoporosis and Osteopenia?
Before the numbers, a few things to keep in mind:
- These are guidelines, not prescriptions.
- Registered nutritionists often disagree on the right dose for a given person.
- Consider working with a registered nutritionist on a plan for your needs.
- Magnesium interacts with several medications. Speak with your pharmacist and your physician.
Recommended Dietary Allowance (RDA), from all sources including food:
- Adult men: 400 mg/day (ages 19 to 30), 420 mg/day (31 and over)
- Adult women: 310 mg/day (ages 19 to 30), 320 mg/day (31 and over)
For bone health, research supports a total intake in the range of 400 to 800 mg of magnesium daily from food and supplements combined, with postmenopausal women at the higher end.
Upper Limits (Supplements Only)
Upper limits apply to supplements only, and they differ by region:
United States: 350 mg per day of supplemental magnesium.
European Union: 250 mg per day.
Neither limit applies to the magnesium in your food. Healthy kidneys clear dietary magnesium efficiently. The limits exist because supplemental magnesium above these levels commonly causes diarrhea.
The practical approach is to build your intake from food first, then supplement to fill the gap, staying within the supplemental limit for your region unless your physician advises otherwise.
Calcium and Magnesium: Does Magnesium Deplete Calcium?
No. Magnesium does not deplete calcium. It directs it.
Magnesium acts as the gatekeeper, controlling the cell’s mineral ion channels. It allows calcium to enter muscle cells and nerve cells, where calcium creates an action potential, and then it opens the channel again to usher calcium back out. Without enough magnesium to guard these gates, calcium floods into cells and causes them to fire continuously until they die. This is what leads to muscle spasms, twitches, and cramping.
Magnesium also has an indirect role in calcium absorption. Magnesium is required for the synthesis and metabolism of vitamin D, and vitamin D drives calcium absorption, so a magnesium deficiency impairs calcium uptake even when calcium intake is adequate.
The right ratio:
A 2023 study published in The Journal of Nutrition found that a calcium-to-magnesium intake ratio within the range of 2.2:1 to 3.2:1 appeared most protective for bone health, associated with higher bone mineral density at all anatomical sites and lower odds of osteoporosis. (9) Anything above or below that range appears to harm bone health.
A practical guideline is 2:1. If you take 600 mg of calcium, pair it with 300 mg of magnesium. The problem in most Western diets is not too little calcium. It is the ratio.
Magnesium-Rich Foods
The best source of magnesium is food. Eating vegetables, nuts, and seeds gets you magnesium alongside the calcium you need, in something close to the right ratio.
- Pumpkin seeds (1 oz = 150 mg)
- Almonds (1 oz = 80 mg)
- Spinach, cooked (½ cup = 78 mg)
- Dark chocolate 70%+ (1 oz = 65 mg)
- Black beans (½ cup = 60 mg)
- Avocado (1 whole = 58 mg)
For most people the practical approach is to stop worrying about getting “enough” calcium, because most of us in the West get plenty, and to actively add magnesium-rich whole foods to every meal while reducing processed foods, which are low in magnesium.
If you want to know where you stand, a few days of logging in Cronometer or MyFitnessPal will tell you. For most people that is not necessary.
Exercise and Magnesium for Bone Health
We know that magnesium plays an important role in Bone health. But is it enough? Get my 7-day email course: the safest exercises to start after an osteoporosis diagnosis
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Who Should Not Take Magnesium
- Kidney function: Your kidneys are how your body clears magnesium. If they are not working at full capacity, magnesium can accumulate. This is not only kidney failure. Chronic kidney disease is enough, and it affects roughly a third of adults over 65, many of whom do not know they have it. If you are over 65, or you have diabetes or high blood pressure, ask your physician for your kidney function before you begin supplementing magnesium.
- Other contraindications: High-dose magnesium should not be given to people with heart block. People with myasthenia gravis should avoid intravenous magnesium.
- Medication interactions: Magnesium can reduce the absorption of several medications, including bisphosphonates used to treat osteoporosis (such as alendronate and risedronate) and tetracycline and quinolone antibiotics. Take magnesium at a different time of day from these medications, and check the timing with your pharmacist. Long-term use of proton pump inhibitors, and of loop or thiazide diuretics, can also deplete magnesium.
- Side effects: Too much supplemental magnesium causes diarrhea, nausea, and abdominal cramping. This is the reason the supplemental limit exists. Magnesium from food does not carry this risk in healthy people.
What Dr. Carolyn Dean Says About Magnesium and Bone
Dr. Dean has argued for magnesium’s importance for longer than almost anyone, and she frames it in a way I have found useful with my own clients.
On the structure of bone, she describes the soft tissue matrix as taking up 30 to 40% of your bone, with magnesium building the scaffolding onto which the calcium deposits. Her image for it: if you have a good foundation to build onto, you can build; without the foundation, you can’t build anything.
On strontium, which comes up constantly with my clients because supplement companies guarantee a DEXA improvement, Dr. Dean is unequivocal. She looked into it and never got behind it. Strontium makes up a minuscule fraction of natural bone, and using hundreds of milligrams for bone density, she says, is using it as a drug. She does not know whether the osteoclasts that remodel bone treat strontium the way they treat calcium, or whether it simply stays put and makes bone brittle. She walked away from it, and so do I.
On calcium supplements, Dr. Dean points to Dr. Bolland’s research from New Zealand, which found that healthy older women taking calcium supplements experienced an increased rate of vascular events. (8) Her advice, and mine, is to get your calcium from your diet where you can.
Where her recommendation differs from published guidance, it is worth being clear. Dr. Dean recommends taking calcium and magnesium in roughly equal amounts, and a supplemental magnesium dose in the range of 450 mg per day. Published guidelines are more conservative on both points: the research supports a calcium-to-magnesium ratio closer to 2:1 or 3:1, and supplemental magnesium above 350 mg per day (250 mg in the European Union) commonly causes digestive upset. I would stay within the published limits, and if you have reduced kidney function, diabetes, or high blood pressure, talk to your physician before supplementing at all.
One note on sources. Dr. Dean told me, in her own words, that she does her research and has a company, rather than dealing one-on-one with patients. That company sells a liquid magnesium she formulated, and she recommends liquid magnesium over the citrate and glycinate forms described above. I have set out the published research on absorption rather than her product guidance, and you can weigh both.
Summary: Building Bone Takes More Than Calcium
Bone health requires a set of nutrients working together:
- Magnesium, for collagen production and the soft tissue matrix
- Calcium, for mineralization, ideally from food
- Vitamin D, for calcium absorption
- Vitamin K2, to direct calcium into bone rather than soft tissue
- Vitamin C, to produce collagen
- Protein, for the bone matrix itself
Think of bone health as building a house. Calcium is like the bricks, but you need the mortar, the framework, the foundation, and skilled builders to create a structure that will last. Magnesium plays multiple roles in that construction.
For decades the bone conversation has been dominated by calcium and vitamin D, with magnesium relegated to a supporting role or ignored entirely. With 60% of your body’s magnesium residing in your bones and building the very foundation that calcium depends on, it deserves better than that.
The next time someone talks to you about bone health, ask them about magnesium.
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FAQs: Magnesium for Bone Health
Which magnesium is best for bone health?
Magnesium citrate has the most direct research evidence for bone health, while magnesium glycinate is better tolerated if you have a sensitive stomach. Both are absorbed considerably better than magnesium oxide, though oxide has still been shown to benefit bone density when combined with calcium. The most important factor is taking an adequate dose consistently, whichever form you choose.
Is magnesium good for bones?
Yes. About 60% of your body's magnesium is stored in your bones, where it helps build the collagen matrix that calcium bonds to, stimulates the osteoblasts that form new bone, and limits the osteoclast activity that breaks bone down. Lower magnesium intake correlates with reduced bone mineral density, particularly at the hip and femoral neck.
Which magnesium is best for bones and muscles?
Magnesium glycinate is a reasonable choice for both, as it is well absorbed and gentle on digestion. In muscle, magnesium acts as the gatekeeper on calcium ion channels: it allows calcium in to create a contraction, then opens the channel again so the muscle can relax. Without enough magnesium, calcium keeps entering the cell, which is why deficiency often shows up as cramps and twitches.
How much magnesium should I take for osteoporosis?
Research supports a total intake of 400 to 800 mg of magnesium daily from food and supplements combined, with postmenopausal women at the higher end of that range. Supplemental magnesium has a separate upper limit: 350 mg per day in the United States and 250 mg in the European Union. Because magnesium interacts with several medications and is unsafe for people with reduced kidney function, confirm your dose with your physician or pharmacist.
Does magnesium deplete calcium?
No. Magnesium does not deplete calcium; it regulates where calcium goes, opening and closing the cell's calcium channels so calcium can do its job and then leave. The real imbalance in modern diets runs the other way: we can take in as much as ten times more calcium than magnesium, when a ratio closer to 2:1 or 3:1 appears most protective for bone.
Does magnesium increase bone density?
It can, particularly alongside calcium. In a 1990 study of postmenopausal women on hormone therapy, combining 500 mg of calcium with 200 mg of magnesium produced an 11% increase in heel bone density over nine months, against 0.7% with dietary advice alone. Larger observational studies associate higher magnesium intake with greater bone mineral density at the hip and femoral neck.
Can magnesium help with osteopenia?
Magnesium supports the bone-building process that osteopenia disrupts, and correcting a deficiency removes one of the drivers of continued bone loss. Magnesium deficiency promotes osteopenia through two pathways: it disrupts parathyroid hormone signaling, and it impairs the synthesis and metabolism of vitamin D. Magnesium on its own will not reverse osteopenia. It works alongside exercise, calcium, vitamin D, and adequate protein.
What type of magnesium is best for calcium absorption?
Magnesium's role is less about absorbing calcium and more about directing it. Magnesium is required for the synthesis and metabolism of vitamin D, and vitamin D is what drives calcium absorption, so a magnesium deficiency indirectly impairs calcium uptake. Citrate and glycinate are the best absorbed everyday forms, and vitamin K2 is what then helps steer calcium into bone rather than into soft tissue.
Margaret Martin
Further Readings
References
- Castiglioni S, Cazzaniga A, Albisetti W, Maier JAM. Magnesium and
Osteoporosis: Current State of Knowledge and Future Research Directions.
Nutrients. 2013;5(8):3022-3033. doi:10.3390/nu5083022 - He LY, Zhang XM, Liu B, Tian Y, Ma WH. Effect of magnesium ion on human
osteoblast activity. Braz J Med Biol Res. 2016;49(7):e5257.
doi:10.1590/1414-431X20165257 - Belluci MM, Schoenmaker T, Rossa-Junior C, Orrico SRP, de Vries TJ,
Everts V. Magnesium deficiency results in an increased formation of
osteoclasts. J Nutr Biochem. 2013;24(8):1488-1498.
doi:10.1016/j.jnutbio.2012.12.008 - Rude RK, Kirchen ME, Gruber HE, Meyer MH, Luck JS, Crawford DL.
Magnesium deficiency-induced osteoporosis in the rat: Uncoupling of bone
formation and bone resorption. Magnes Res. 1999;12(4):257-267. - Abraham GE, Grewal H. A total dietary program emphasizing magnesium
instead of calcium. Effect on the mineral density of calcaneous bone in
postmenopausal women on hormonal therapy. J Reprod Med.
1990;35(5):503-507. - Groenendijk I, van Delft M, Versloot P, van Loon LJC, de Groot LCPGM.
Impact of magnesium on bone health in older adults: A systematic review
and meta-analysis. Bone. 2022;154:116233. doi:10.1016/j.bone.2021.116233 - Rondanelli M, Faliva MA, Tartara A, Gasparri C, Perna S, Infantino V,
Riva A, Petrangolini G, Peroni G. An update on magnesium and bone health.
Biometals. 2021 Aug;34(4):715-736. doi:10.1007/s10534-021-00305-0.
Epub 2021 May 6. PMID: 33959846; PMCID: PMC8313472. - Bolland MJ, Barber PA, Doughty RN, et al. Vascular events in healthy
older women receiving calcium supplementation: randomised controlled
trial. BMJ. 2008;336(7638):262-266. doi:10.1136/bmj.39440.525752.BE - Fouhy LE, Mangano KM, Zhang X, Hughes BD, Tucker KL, Noel SE. Association
between a Calcium-to-Magnesium Ratio and Osteoporosis among Puerto Rican
Adults. J Nutr. 2023 Sep;153(9):2642-2650. doi:10.1016/j.tjnut.2023.05.009.
Epub 2023 May 9. PMID: 37164266; PMCID: PMC10550845. - Researcher: Balance of Key Minerals Helps to Prevent Weak Bones.
UMASS Lowell.
https://www.uml.edu/news/stories/2023/research-osteoporosis.aspx - Liu Lin, Luo Pan, Wen Pengfei, Xu Peng. The role of magnesium in the
pathogenesis of osteoporosis. Frontiers in Endocrinology. Volume 15,
2024. https://www.frontiersin.org/journals/endocrinology/articles/10.3389/fendo.2024.1406248
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