Bone Scan Myths

What Your DEXA Scan Can Tell You, What It Cannot, and Why Treating a Number Instead of a Human Being Can Backfire

If you have been told you need a bone drug because your DEXA scan says you have osteopenia or osteoporosis, you need to understand something important:

A DEXA scan measures bone mineral density. It does not measure the full biology of bone strength. It does not tell you why your bones are weakening. And it does not always distinguish true pathological bone loss from constitutional differences in body size, genetics, skeletal structure, or other forms of biochemical individuality.

That does not make DEXA worthless. It makes it limited.

The problem is that in the real world, many patients are funneled into treatment discussions that are solely based on the DEXA score. Yet current expert guidance says osteoporosis treatment should be individualized and should account for fracture history, fracture timing and severity, overall risk profile, and more than just the T-score.

The 2024 Bone Health & Osteoporosis Foundation (BHOF) task force specifically states that treatment should be tailored to the individual patient’s risk profile and argues against a one-size-fits-all “bisphosphonate first for everyone” model.

So let’s clear up some of the biggest myths.

Myth #1: A DEXA scan tells me whether my bones are truly strong

Not exactly.

DEXA is a 2-dimensional test that reports areal bone mineral density, but not bone strength.  This is a critical distinction because real bone strength depends on more than mineral quantity. It also depends on trabecular microarchitecture, cortical thickness, porosity, collagen integrity, turnover dynamics, and whether the bone is repairing microscopic damage normally. DEXA tests do not measure all of this.

Bottom line: A DEXA scan provides limited data about bone status, and should not be used as the sole determinant starting treatment with medication.

Myth #2: If my DEXA score is not in the osteoporosis range, my fracture risk is low

A large clinical reality is that many fractures occur in people who do not have osteoporosis by DEXA criteria.  Research has found that the majority of fragility fractures occur in patients with DEXA diagnosed osteopenia, not osteoporosis.

The University of Leeds-linked 2022 paper you mentioned gets at this problem in a very important way. In one study done at the University of Leeds, researchers found that almost half of fragility hip fractures occurred in women with femoral neck T-scores above -1.5, far from the classic osteoporosis cutoff of -2.5.

That means a “better-than-expected” DEXA result can still miss meaningful fracture risk.

Myth #3: DEXA accounts for biochemical individuality

It does not.

One of the biggest flaws in over relying on DEXA is that it tells you nothing about why your BMD is what it is.

Two people can have the same T-score and have completely different biological reasons for getting there. One may have celiac disease or gluten-triggered malabsorption. Another may have hyperparathyroidism. Another may be protein deficient. Another may have low vitamin D, low magnesium, low vitamin K intake, low estrogen, chronic inflammation, thyroid hormone overdosing, steroid exposure, or poor muscle mass. DEXA does not sort that out. It is a density measurement, not a root-cause evaluation.

This is where biochemical individuality matters. Bone is living tissue. It responds to digestion, absorption, inflammation, hormones, genetics, nutrient status, load-bearing exercise, and medication exposure. A printout cannot capture that complexity.

If you treat the number and ignore the biology, you may miss the real reason the bone is weak.

Myth #4: Bone density is mostly the same for people of the same age

No.

Bone mineral density varies substantially from person to person, and genetics play a major role. Reviews and genetic studies report that about 50% to 85% of the variance in BMD is heritable. In other words, inherited biology strongly influences skeletal density and geometry long before a person ever develops age-related bone loss.

This matters clinically because people do not all start from the same baseline. One person may naturally achieve a higher peak bone mass. Another may have a smaller frame and lower areal BMD but still not have the same structural weakness that the scan number seems to imply. Another may carry high-BMD genetic variants. Another may have a skeletal phenotype that makes interpretation more complex.

Age matters. Menopause matters. Inflammation matters. But the same raw DEXA number does not mean exactly the same thing in every human being.

Myth #5: A low DEXA score always means true pathological bone loss

Not always.

This is especially important in smaller-framed individuals.

Because DEXA measures areal density rather than true volumetric density, the result is influenced by bone size. Reviews note that areal BMD is susceptible to body and bone size and may overestimate fracture risk in individuals with a small body frame, who can register lower areal BMD simply because their bones are smaller.

The same concern has been raised by researchers on premenopausal women and other smaller-framed populations. Researchers note that DXA is affected by bone size and that low areal BMD in people with smaller bones raises an important question: are they truly low in volumetric density and bone strength, or are they being mischaracterized by the limitations of the measurement itself?

That means an osteoporotic or near-osteoporotic T-score does not always cleanly separate true disease from variation in frame size, inherited traits, or normal diversity. This is one reason a scan result should never be interpreted in a vacuum.

Myth #6: A high DEXA score always means healthy, fracture-resistant bone

Also false.

High BMD on DXA can be misleading. A major review notes that elevated BMD on routine scanning often reflects degenerative disease, and high values may also result from vascular calcification, spinal osteoarthritis, vertebral fracture changes, or other local artifacts and disorders. That means a “good” number can sometimes be falsely reassuring.

So low numbers can be misleading. High numbers can be misleading. Context matters.

Myth #7: DEXA scans are straightforward and objective, so they rarely mislead

This is wishful thinking.

Mistakes in acquisition, positioning, analysis, and interpretation are not rare. Reviews on clinical DXA use and technical pitfalls describe frequent problems involving patient positioning, scan analysis, artifacts, degenerative change, and reporting errors that can influence diagnosis and treatment decisions.

That means the machine may be precise, but the real-world test is still vulnerable to human and technical error.

Myth #8: If my DEXA says osteoporosis, medication is automatically the right next step

This is where modern medicine often gets it wrong.

Using a DEXA score as the main or only reason to prescribe medications is not good medicine.

Current guidance supports individualized treatment based on the patient’s overall risk profile, including site, number, and severity of prior fractures, plus BMD levels. It specifically says that instead of defaulting to first-line bisphosphonate treatment for all patients, initial therapy should be chosen based on how rapidly fracture risk needs to be reduced and how high the patient’s overall risk is.

In plain English, that means the standard “your scan is low, here is your bone drug” approach is too simplistic.

The problem with prescribing bone drugs from a DEXA-centered model

When medications are prescribed mainly from a scan number, several major problems can happen.

1. The true cause of bone loss may be missed

If the real problem is gluten sensitivity, celiac disease, low protein intake, vitamin D deficiency, magnesium depletion, medication-induced nutrient depletion, thyroid disease, sex hormone loss, chronic inflammation, or poor digestion, a bone drug does not solve the root cause. It may change the scan while leaving the biology uncorrected.

2. Long-term suppression of bone turnover can create new risks

This is where patients are often not adequately informed.

Bone is alive. Healthy bone is constantly being remodeled. Osteoclasts remove old or damaged bone. Osteoblasts lay down new bone. That turnover is not a design flaw. It is part of how bone repairs itself.

Long-term use of powerful antiresorptive drugs, especially bisphosphonates, suppresses remodeling. That can reduce common osteoporotic fracture risk in many patients, but with prolonged use it may also allow microdamage to accumulate and bone tissue to become older, more highly mineralized, and less tough. Reviews of atypical femur fractures describe this mechanism as one involving remodeling suppression, microdamage accumulation, and increased mineralization of older bone tissue.

This is why atypical femoral fractures have become a recognized long-term complication of prolonged bisphosphonate therapy. The paradox is that the scan may look denser while some aspects of tissue quality worsen.

4. Osteonecrosis of the jaw is a real complication, and it is likely undercounted

Medication-related osteonecrosis of the jaw, or MRONJ, is one of the most feared complications of antiresorptive therapy.

Yes, published estimates in osteoporosis-dose patients are often low. The AAOMS 2022 position paper reports low estimated risk ranges for osteoporosis patients using antiresorptives. But that does not mean the true burden is fully captured.

The literature is very clear that under-recognition and under-reporting have been a real issue. In fact, the AAOMS broadened the diagnostic definition in its 2014 update specifically to address evolving clinical observations and concerns about under-reporting. That change expanded the definition beyond visibly exposed bone alone to include bone that can be probed through a fistula.

This is an important distinction because narrow definitions miss cases. Delayed recognition misses cases. Poor awareness among clinicians misses cases. So when you hear that osteonecrosis is “rare,” you should understand that those numbers reflect documented cases, not necessarily every case that occurs in real-world practice. The safest, most evidence-based way to say it is that the true incidence is likely underestimated.

Rare does not mean impossible. And rare does not mean fully counted.

Why long-term bone drug use can increase fracture risk

This is one of the great ironies in osteoporosis care.

Many bone drugs are designed to reduce fractures.  But with long-term bisphosphonate exposure, a different problem can emerge.

When remodeling is suppressed too strongly for too long, bone can become over mineralized and brittle. More precisely, the tissue can become older, microdamage can accumulate, and the normal repair cycle can be impaired. That is why long-term use has been linked to atypical femoral fractures.

So while the average doctor informs the patient that “this drug builds stronger bones,” the deeper truth is more nuanced: some of these drugs can make the bone denser on paper while driving the production of poor quality bone more prone to fracture risk. This is not a reason to panic, but it is a reason to stop pretending that the DEXA score tells the whole story.

What a more intelligent bone evaluation looks like

A smarter approach to bone health asks better questions.

Instead of only asking, “What is the T-score?” the following questions should be asked:

• Have there been prior fractures?
• Is there evidence of silent vertebral compression fractures?
• Are you small-framed, making areal BMD less reliable?
• Are there signs of celiac disease, gluten sensitivity, malabsorption, or chronic gut inflammation?
• What is your overall nutritional status?
• Do you have a chronic inflammatory condition that contributes to bone issues?
• Do you have a abnormal hormone levels? – i.e. Parathyroid, thyroid, estrogen, testosterone, progesterone, DHEA, insulin, cortisol, etc.
• Are you taking steroids, acid blockers, SSRIs, anticonvulsants, thyroid medication, or other drugs that can affect bone?
• Are you building muscle and mechanically loading bone through appropriate exercise?
• Do you have lifestyle factors known to contribute to bone loss?  Smoking, alcohol, sedentary, etc.
• Do you get adequate sleep?
• Do you get adequate sun exposure (main source of vitamin D)?
• Are you overly stressed?

In addition, a more comprehensive laboratory assessment should also be part of your evaluation.  When these tests are used together, a more complete picture is painted, allowing for your doctor to create a more comprehensive bone evaluation, treatment, and monitoring program.

• Osteocalcin (blood)- A vitamin K dependent hormone derived from bone building cells that drives bone mineralization and density.  Elevated levels indicate increased bone breakdown.  (Discontinue use of biotin supplements at least 3 days before measuring.
• Alkaline Phosphatase (blood) – an enzyme made by bone cells.  Low levels may indicate poor bone building.  This marker is linked to insufficient zinc, magnesium, phosphorous, and protein.
• N-telopeptides (NTX – urine) – NTX are small collagen fragments from bone.  Elevated levels can indicate rapid bone breakdown and possible osteoporosis risk.
• Deoxypyridinoline (DPD – urine) – DPD is a peptide responsible for stabilizing type I collagen.  Elevated levels can indicate more rapid bone breakdown.  This peptide is dependent on sufficient vitamin C and copper.
• Intracellular Nutrient Analysis (INA-blood) – The INA test measures vitamins, minerals, amino acids, and other nutrients required for healthy bone formation and maintenance.  In my opinion, this test is the most important and comprehensive test to assess nutritional needs for bone health.

When all of the above is taken together, the doctor and patient are more empowered, more educated, and have a much deeper picture for what is necessary to support bone health.  That is how you move from scan-based medicine to root-cause medicine.

The bottom line

A DEXA scan has value. It can help identify low bone mass. It can help track change over time. It can contribute to fracture-risk assessment.

But it is not a complete bone-strength test. It does not account for biochemical individuality. It does not fully account for genetics. It does not fully correct for body size. It does not reveal the root cause of bone loss. It can miss structural fragility. It can be distorted by artifact. And when it becomes the primary driver of automatic medication prescribing, patients can be exposed to long-term complications while the underlying reason for their bone weakness remains untreated.

The real question is not just, “What does your scan say?”

The real question is, why are your bones weak in the first place, and what is the most intelligent way to restore bone strength without creating new problems?

That is the conversation more patients should be having with their doctors.

FAQ: Bone Scan Myths, DEXA Scan Limitations, and Bone Drug Risks

What does a DEXA scan really tell you about bone health?

A DEXA scan tells you how much mineral appears to be in your bones. That can be useful, but it does not tell you everything that matters about bone health. It does not directly measure bone quality, collagen integrity, repair capacity, or the root causes of bone loss.

What does a DEXA scan not tell you?

A DEXA scan does not tell you why your bone density is low. It cannot identify whether bone loss is being driven by gluten sensitivity, celiac disease, malabsorption, nutrient deficiencies, hormone imbalance, chronic inflammation, medication side effects, or poor digestion. That is one of the biggest DEXA scan limitations.

Is bone density the same as bone strength?

No. Bone density is not the same as bone strength. Bone strength also depends on microarchitecture, collagen quality, mineral balance, bone turnover, and the ability to repair microscopic damage. A DEXA scan may show density, but it does not fully show bone quality.

Can a DEXA scan miss fracture risk?

Yes. One of the major bone scan myths is that a person is only at risk if the DEXA scan shows osteoporosis. Many fragility fractures happen in people with osteopenia, not just in those with full osteoporosis by DEXA criteria. That means a DEXA scan can miss important fracture risk.

Why can DEXA scan results be misleading in small-framed people?

Because DEXA measures areal density rather than true volumetric density, people with smaller bones can appear to have lower bone density on paper even when their actual bone quality is not proportionately worse. This is one reason DEXA scan results can be misleading in smaller-framed individuals.

Can a DEXA scan misclassify osteoporosis?

Yes, in some cases it can. A low score does not always mean true pathological bone loss, and a higher score does not always mean healthy, fracture-resistant bone. Body size, inherited skeletal traits, degenerative changes, calcification, and scan artifacts can all affect interpretation.

Can a high DEXA score give false reassurance?

Yes. A higher DEXA score does not always mean stronger or healthier bone. Degenerative disease, osteoarthritis, calcification, vertebral changes, and other artifacts can make the score look better than the true clinical situation.

Are DEXA scans always accurate?

No. DEXA scans are useful, but they are not perfect. Positioning errors, scan-analysis errors, artifact, and interpretation mistakes can all influence the result. That means DEXA scans should not be treated as infallible or used without clinical context.

Should osteoporosis medication be prescribed based only on a DEXA score?

No. Prescribing osteoporosis medication based only on a DEXA score is too simplistic. Bone treatment decisions should also take into account fracture history, body frame, symptoms, lifestyle, gut health, nutrient status, hormones, inflammation, medication use, and the root causes of bone loss.

What are the problems with prescribing bone drugs based only on DEXA scan results?

The biggest problem is that the true cause of bone loss may be missed. If the real issue is gluten sensitivity, celiac disease, poor digestion, low protein intake, vitamin or mineral deficiencies, hormone imbalance, inflammation, or medication-induced bone loss, a bone drug does not solve the underlying problem. It may change the scan while leaving the biology uncorrected.

What are the long-term bisphosphonate side effects people should know about?

Long-term bisphosphonate side effects can include over suppression of bone turnover, accumulation of microdamage, aging of bone tissue, increased brittleness, and atypical femur fractures. Bone may look denser on paper while becoming more fragile in real life.

Can long-term bisphosphonate use increase fracture risk?

Yes. That is one of the great ironies of long-term osteoporosis drug use. When bone remodeling is suppressed too strongly for too long, bone can become over mineralized, older, and more brittle. This is why long-term use has been linked to atypical femoral fractures.

Is osteonecrosis of the jaw from bisphosphonates a real risk?

Yes. Osteonecrosis of the jaw is a real complication of antiresorptive therapy. It may also be undercounted because of under-recognition, narrow definitions, delayed diagnosis, and under-reporting. Rare does not mean impossible, and it does not always mean fully counted.

What are the real root causes of low bone density?

Low bone density can be driven by many different root causes, including gluten sensitivity, celiac disease, malabsorption, low protein intake, nutrient deficiencies, chronic inflammation, thyroid problems, sex hormone imbalance, stress, poor sleep, inactivity, smoking, alcohol use, and medication side effects.

How should bone health be evaluated beyond a DEXA scan?

A more complete bone health evaluation should look beyond the T-score. It should include fracture history, silent vertebral fracture risk, body frame size, digestive health, gluten sensitivity, nutritional status, inflammation, hormone levels, medication review, exercise habits, sleep, sun exposure, and stress burden.

What lab tests can help evaluate bone health more intelligently?

Helpful labs can include osteocalcin, alkaline phosphatase, urinary N-telopeptides, urinary deoxypyridinoline, and Intracellular Nutrient Analysis. These tests can help uncover poor bone building, accelerated bone breakdown, and nutritional insufficiencies that a DEXA scan cannot detect.

What is the biggest myth about bone density scans?

The biggest myth is that a bone density scan tells the whole story. It does not. A DEXA scan is one tool, and a limited one. The most important question is not just what the scan says, but why the bones are weak and what needs to be done to restore true bone strength.