An illustrated guide · through 2026

Understanding bone health — beyond density.

The scans that see more, and the real causes — iron, body weight, hormones & light. A plain-language guide that keeps the science intact. Written with women at the center; useful to everyone.

Get the free guideExplore the science ↓
~1 in 2
women over 50 will break a bone from fragile bone
Bone Health & Osteoporosis Foundation, Fast Facts (2024)
~3 in 4
fragility fractures strike people not classed “osteoporotic” by density
≈70–75% occur above the osteoporosis threshold — NORA (Siris 2004); reaffirmed by Mayo Clin Proc 2024
0–100
the REMS Fragility Score for bone quality
Adami et al., Aging Clin Exp Res 2023; systematic review, Diagnostics 2025
Josi Clary
Josi Clary
Bone-health coaching & education
Quality
not just quantity
~1 in 2
women over 50 will break a bone from fragile bone
Bone Health & Osteoporosis Foundation, Fast Facts (2024, US figure)
up to 1 in 4
men over 50 — so this matters for everyone
Bone Health & Osteoporosis Foundation, Fast Facts (2024, US figure)
~3 in 4
fragility fractures strike people density alone calls “not osteoporotic”
≈70–75% occur above the osteoporosis threshold — NORA (Siris 2004); reaffirmed Mayo Clin Proc 2024
1 in 300
carry higher-risk hereditary iron overload
HFE (C282Y) homozygosity in people of N. European descent; Osteoporosis Int.
How to read this

Honest about the evidence

Throughout, every claim is tagged so you can tell solid ground from open questions.

Established

Strong, repeated evidence in humans. You can rely on this.

Emerging

A real mechanism with growing support, but the human evidence is still incomplete. Reasonable to act on the low-risk parts.

Promising / debated

Genuine support and active scientific disagreement. Worth knowing and using thoughtfully — not yet the final word.

Why this centers on women

Menopause changes bone fastest

After menopause, the drop in estrogen makes women lose bone faster than men, and women face more fragility fractures over a lifetime. So this guide foregrounds the female experience — menopause, estrogen, very low body weight.

♂ Relevant for men too

Where a point applies equally to men, you'll see this marker — and the biology, including the iron and hormone stories, is shared by both. Up to 1 in 4 men over 50 will fracture from fragile bone.

01 · The big idea

Bone health is more than “density”

Density tells you how much bone there is. It does not tell you how well that bone is built — the honeycomb lattice inside, the protein scaffolding, the overall shape. Quality, not just quantity, decides whether a bone breaks.

Interactive · The central idea
Same mineral, very different strength

The green dots (mineral) stay the same — so density is constant. Only the internal architecture changes. Drag to rebuild the lattice, then press load.

same
Density (mineral)
44/100
Structural strength
High
Fracture risk

This is why relying on density alone misses most of the people who eventually fracture — around 70–75% of fragility fractures happen to people who aren’t “osteoporotic” on a scan — and why the newer scans that measure quality (Section 3) have drawn so much interest.

“Density tells you how much bone there is. Quality tells you whether it will hold.Aim to understand both.”

02 · Foundations

How your bones actually work

Bone is not dead scaffolding — it's living tissue, constantly torn down and rebuilt in a process called remodeling. Almost every cause of osteoporosis works by tipping one balance.

Interactive · Foundations
The daily balance

Builders (+) lay down bone; removers (–) clear it. Choose a cause and watch it tip the same scale.

60%
Relative bone
Steady
Direction
Even
Who's winning

Builders and removers keep pace. Bone is maintained.

03 · Diagnosis

Seeing what DEXA misses

If bone strength is about quality as well as quantity, then how we measure bone matters enormously. Here are the main tools — from the familiar standard to the newer technologies — with REMS in depth.

Interactive · Diagnosis
Why DEXA can read “falsely reassuring”

A flat X-ray adds up everything in its path. Toggle the artifacts and watch the DEXA score inflate — while REMS, reading echoes, holds to the true bone signal.

high ↑
DEXA can read
true ✓
REMS reads
57/100
REMS Fragility Score

The honest counterweight: DEXA remains the diagnostic gold standard, and most physicians won't change medication on REMS alone. REMS is best used as a complement — especially where arthritis, calcification, or very low body weight make DEXA least reliable.

At a glance: how the main tools compare

FeatureDEXATBSREMS
Main outputDensity, T-scoreTexture add-onDensity + Fragility Score
Quality info?LimitedYes (texture)Yes (Fragility Score)
RadiationLow-dose X-rayUses DEXA imageNone (ultrasound)
SitesSpine, hipSpineSpine, hip
Fooled by artifacts?Yes (often)PartlyResistant
Portable?No—Yes
StatusGold standardAccepted add-onPromising, debated
Best roleDiagnosis & treatmentRefine riskComplement; monitor; artifact / thin cases

The richest picture combines a DEXA (diagnosis) with a quality measure (TBS and/or REMS's Fragility Score) and a FRAX risk estimate. These tools are layers, not rivals.

03·5 · Josi's conviction

The full picture beats a single number

This is the idea Josi is most excited about: don't settle for one test. She's in favor of layering REMS + DEXA + biomarkers + movement together — quantity, quality, risk, root causes, and function — for the clearest, safest read on your bones.

Interactive · Josi's approach
See the whole picture, not one number

No single test tells the whole story. Layer the lenses together — the way Josi believes bone health should be assessed — and the picture gets clear.

Full picture ✓

These tools are layers, not rivals. DEXA remains the diagnostic standard; REMS and TBS add the quality density misses; FRAX frames the risk; biomarkers reveal the root causes; movement decides the outcome. Bring the whole picture to your doctor.

VW
Dr. Vonda Wright
Orthopedic surgeon · advocate for
women's musculoskeletal longevity
The mission Josi leans into

Moving mountains for women's health

Dr. Vonda Wright — an orthopedic surgeon and one of the most prominent voices on active aging — has made it her mission to close the research gap in women's musculoskeletal health. Her message is the one Josi returns to most: the menopausal body has been under-studied for far too long, and bone, muscle, and mobility are the pillars of a long, strong life.

“Don't wait to be diagnosed. Get the full picture — and act early.”

It's why Josi wants the whole picture — REMS + DEXA + biomarkers, movement and strength together — rather than a single number. And it's why she supports Move the Mountain at the Buck Institute, the campaign advancing exactly this science.

Support Move the Mountain ↗See the full-picture approach

Dr. Vonda Wright is featured here for educational and informational purposes. Her name is used descriptively and this does not imply her endorsement, sponsorship, or affiliation. Josi Clary Coaching is independent of, and not affiliated with, Dr. Wright or the Buck Institute.

04–05 · Causes

What weakens bone — including the overlooked

The familiar causes are real: estrogen loss after menopause (and low testosterone in men), aging, too little calcium/vitamin D/protein or loading, and certain medications. But two causes rarely make the standard conversation — and both can be missed for years.

An overlooked cause · Iron
Excess iron attacks bone three ways at once

The body needs iron, but too much is toxic to bone — and the science behind why matured sharply in just the last two years.

Emerging
Feexcess iron
1
Direct toxicity
Ferroptosis — an iron-driven form of cell death — kills the builder cells (osteoblasts) while revving up the removers.
2
Hormone disruption
Iron overload lowers protective sex hormones — estrogen and testosterone — removing a brake on bone loss.
3
Oxidative stress
Iron fuels internal “rusting” that damages cells throughout bone — the shared hub that ties the causes together.
Hemochromatosis — when this isn't hypothetical

Hereditary iron overload is not rare — roughly 1 in 300 people of Northern European descent carry the higher-risk version. In studied groups, a quarter to a third had outright osteoporosis. A simple, inexpensive blood panel — ferritin and transferrin saturation (plus HFE genetic testing if high) — can reveal a cause of bone loss that would otherwise go unexplained for years.♂ Often affects men earlier

06 · Body weight

Why being very thin carries its own risk

Most conversation about weight focuses on carrying too much. For bone, the opposite end deserves equal attention. Being significantly underweight is a well-established, independent risk factor for fracture — several forces, all pushing one direction.

↓ Estrogen

After menopause, body fat is a main source of estrogen. Very thin means little of this protective tissue.

↓ Mechanical loading

Less body weight means a weaker daily 'build' signal to bone.

↓ Muscle

Low weight tracks with muscle loss — more falls, and less cushioning over the hip when one happens.

↓ Nutrient reserve

You cannot build strong bone without enough protein, minerals, and energy.

↓ Leptin & signals

Fat tissue makes hormones such as leptin that appear to support bone; very low fat means low levels.

A nuance about scans

In a very lean person a DEXA score can understate true risk. A number that looks "not too bad" shouldn't be falsely reassuring — exactly where a quality measure (TBS / REMS) and FRAX add value.

07 · Hormones

Estrogen & the menopause window

Because estrogen keeps the remover cells in check, the menopausal drop is the single biggest reason women lose bone rapidly in the years right after menopause — the window where protection matters most.

Interactive · Hormones
The menopause window

Estrogen falls first; bone density follows, fastest in the early years after menopause. Drag across the timeline.

Early post-menopause
Life phase
42%
Estrogen (relative)
76%
Bone density (relative)

Established  This is why hormone-based approaches exist — and why the timing and delivery of any therapy is a careful, individualized conversation with a physician.♂ In men, low testosterone acts similarly

Established

Menopausal hormone therapy reliably preserves bone and reduces fractures. Whether it suits you depends on age, time since menopause, history, and delivery — a decision to make with a physician, not from a guide.

Emerging

Delivery route matters: transdermal (patch/gel) and oral estrogen differ in risk profiles, and FDA-approved "body-identical" hormones differ from custom compounded preparations. Worth raising specifically.

08 · The unifying idea

The common thread: oxidative stress

Excess iron, the loss of estrogen, ordinary aging, and a disrupted body clock all converge on one thing inside bone: oxidative stress — a kind of internal "rusting." Much of what protects bone works by keeping this fire low.

Interactive · The unifying idea
One shared hub ties the causes together

Toggle each cause. Separate-seeming problems feed the same fire — and much of what protects bone works by keeping that fire low.

EmergingYou need not act on this directly — it's the idea that connects the whole guide.
09 · Nutrition

Diet: what genuinely helps

For someone underweight, the priorities flip from the usual "eat less" messaging. The dominant problem is shortage, not excess.

Established

Enough total food

For a very thin person, simply eating enough so the body isn't breaking down its own muscle and bone comes before everything else.

Established

Protein

Bone is roughly half protein by volume. Aim higher than the minimum — about 1.0–1.2 g per kg (≈ 0.45–0.55 g per lb) of body weight daily, spread across meals.

Established

Calcium & vitamin D

The foundation; vitamin D lets the body absorb calcium. Deficiency turns up again and again in bone loss.

Emerging

Supporting cast

Magnesium, vitamin K2 (steers calcium into bone, not soft tissue), and adequate — not excessive — vitamin A.

The iron paradox — please read before adding iron

This is the single most important caution in the guide. A thin, tired older person is often told to "build up" with iron-rich red meat and vitamin C. But if that person has iron overload, this advice flips and becomes harmful to bone. Don't take iron unless a deficiency is confirmed; go easy on heme iron; avoid pairing vitamin C with iron-rich meals. The bottom line: get the iron blood tests before anyone starts pushing iron.

10–11 · Light, rhythm & movement

Loading is signal; light is fuel

Bone strengthens when loaded — and one light–bone link is rock-solid while others are still unsettled. Keep them separate, and load safely.

Established

Sunlight → vitamin D

UVB lets the body make vitamin D, essential for absorbing calcium and mineralizing bone. For many indoor or frail people, a supplement is the practical route.

Emerging

Your body clock

Bone turnover follows a 24-hour rhythm; disrupting it (shift work, poor sleep, light at night) is linked to worse bone. Get morning daylight; keep nights dark.

Promising / debated

Wavelength protocols

Claims that specific light "powers" bone beyond vitamin D are unproven. Take the curiosity seriously; hold the specific prescriptions loosely.

Interactive · Movement
Load becomes signal

Deform bone and it generates faint electricity; the embedded cells read it as a cue to build. It's part of why loading tells bone to keep itself strong.

1.44 mV
Signal generated
1350 µε
Microstrain
Cell: quiet
Response

Established  Weight-bearing and progressive strength training signal bone to maintain and build itself. Promising / debated  Some vibration and electrical therapies aim to tap this same language — worth watching, not yet settled.

Interactive · Movement
Impact → bone signal

Bone listens to peak force, not minutes. A few crisp landings can cross a threshold that hours of gentle activity never reach.

3.4×
Peak force (bodyweights)
476 lbf
Peak force · (2119 N)
Signal sent
≈ 1856 µε
Load safely

Impact and heavy resistance are powerful for bone — but if you have low bone density, a prior fracture, or you're frail, this belongs in a supervised, progressive program cleared by your physician or physiotherapist. Balance training and removing home fall-hazards matter just as much: many fractures are a fall problem as much as a bone problem.

12 · Be your own advocate

Questions & tests to raise with a doctor

None of this replaces a clinician who can see your actual numbers. But these are concrete, low-cost things you can ask about by name.

TBS (Trabecular Bone Score) re-reads your existing DEXA image to estimate bone-quality texture — no extra scan or radiation. If your center offers it, it's worth requesting.

13 · Treatment landscape

Two levers: build more, or remove less

Medicines don't replace bone in a simple way — they tip the build-versus-remove balance to reduce fractures. A doctor matches the choice to the person's risk.

Remove less

Antiresorptives

Bisphosphonates and denosumab slow bone breakdown — the long-standing backbone. Established

Build more

Anabolic agents

Teriparatide and abaloparatide actively stimulate new bone. Established

Both

Romosozumab

Builds bone and slows breakdown. For very high risk, often build first, then lock in gains. Carries a heart-related warning — cardiovascular history is reviewed first. Established

On the horizon. Emerging  Researchers are pursuing broader bone-formation pathways and treatments aimed at the iron / oxidative-stress process itself. A late-2025 regulatory change in how trials are judged is expected to speed new drugs along.

✓ Take action

A simple starting checklist

If you take nothing else from this guide, these steps capture the heart of it.

Tap each step as you go — a simple starting plan.

0 / 7 done
Test yourself

Do you speak bone?

Five questions drawn straight from the guide. Each answer teaches the idea behind it.

Test yourself · 1 / 5Score 0

A DEXA scan measures how much mineral is in bone. What does that number NOT capture?

From the Journal

Longform, evidence-graded reporting

Josi's writing on the science behind the headlines.

Analysis · Diagnosis

The Fracture Factor

The scan we trust to catch fragile bones misses most of the people who break them. The reason is a line drawn thirty years ago for bookkeeping — and everything it leaves out.

By Josi Clary · 2026 · 11 min read →
Analysis · Bone Health

The Weight Is Coming Off Faster Than Ever. Almost Nobody Is Watching the Bone.

A hormone discovered by accident in 1994 explains why the body fights weight loss so hard — and why the newest drugs that finally win that fight can quietly send the invoice to your skeleton.

By Josi Clary · 2026 · 12 min read →
Josi Clary
About

Josi Clary

Josi's aim is plain: give you a clear, well-researched understanding of your own body, so you can ask sharper questions and make better decisions about your health.

This resource grew out of her Understanding Bone Health guide — written with women at the center, because the menopausal years change bone the fastest, though it matters for everyone. It doesn't water down the science, and it says plainly where the evidence is solid and where it's still being argued over. No scare tactics, no hype.

Get the free guideSupport the mission
Free · the full 30-page guide

The complete Understanding Bone Health guide

An illustrated, plain-language deep dive — the anatomy of strong bone, the scans that see more, the iron and hormone stories, and a simple starting checklist. Written for a real person, not a doctor, and honest about what the science does and doesn't yet know. It's Josi's gift to you.

  • Evidence-graded: Established · Emerging · Promising/debated
  • Centered on women's health — essential for men, too
  • The exact questions and tests to bring to your own doctor

Send me the guide

Enter your email and the PDF is yours instantly.

By requesting the guide you agree to our Privacy Policy and to receive occasional emails (unsubscribe anytime). Educational only · not medical advice · no spam.

The scale of it

A global problem, still under the radar

Few diseases touch so many of us as we age — and most of it is silent until a bone breaks.

500 million
people worldwide are living with osteoporosis
International Osteoporosis Foundation (estimate for 2025)
13.5 million
fragility fractures are expected worldwide every year
International Osteoporosis Foundation (estimate for 2025)
Move the Mountain · Buck Institute

Help move mountains for women's health.

Josi stands behind Move the Mountain — the Buck Institute's mission, championed by Dr. Vonda Wright, to close the research gap in women's healthy aging. Bone, muscle, and mobility decide whether we stay strong and independent for life — and for too long the science of the menopausal body has been under-studied. Your gift funds the research that changes that.

  • Funds leading research into women's musculoskeletal longevity
  • Backs the "full picture" approach Josi believes in
  • 100% of your gift goes to the Buck Institute

Give to the mission

Choose an amount to see its impact, then give securely at the Buck Institute.

$50 — Supports research into why women lose bone and muscle faster after menopause.

Give $50 at the Buck Institute ↗

You'll be taken to buckinstitute.org to complete your gift securely.

Donations are made directly to the Buck Institute, a separate registered nonprofit, on its own website and subject to its terms and privacy policy. Josi Clary Coaching does not process, collect, or retain any part of your gift, and receives no commission. Please consult the Buck Institute regarding the tax treatment of your donation. See our Terms of Use.

Reference · FAQ

Go deeper

Not today. REMS density correlates strongly with DEXA and has been FDA-cleared since 2018, and a 5-year study found its Fragility Score predicted fractures. But an active 2025–2026 debate notes that much of REMS density variation can be explained by age and weight, and it's operator-dependent. DEXA remains the gold standard for diagnosis and treatment decisions. The fair takeaway: REMS is a valuable complement, especially where DEXA struggles.

Important — educational, not medical advice. This resource is for general education only and cannot account for any individual's full health picture. Please use it to inform a conversation with a qualified physician, who can interpret your own results and tailor a plan to you. Evidence labels reflect the general state of research and may evolve. Sources include peer-reviewed research on REMS (Aging Clin Exp Res, 2023–2024; Calcified Tissue Int, 2024), ferroptosis and bone (Biology, 2025), iron overload and hemochromatosis (Osteoporosis Int), underweight and fracture risk (Scientific Reports, 2023), protein for bone (Frontiers in Nutrition, 2024), and melatonin and bone (J Pineal Research, 2025).