What is Osteoporosis, Really?

What is Osteoporosis, Really?

I’ve been present for more bone density studies than I can count, and I’ve watched the same osteoporosis myths repeat in exam room after exam room. As the chiropractor and neuromusculoskeletal lead on a research team, I was responsible for the clinical assessment side: examining patients and correlating what a scan showed with what I could see and feel in someone’s structure, posture, and movement. That work, at a research foundation in New York, tied bone density to blood work, cognitive testing, and age. Some of it was published: parathyroid hormone, bone density, and a marker of brain processing speed called P300 latency, all moving together in the same patients.

A note on how this series is written. Three kinds of statements appear in these posts, and I’m keeping them visibly separate. Published research findings are attributed and cited so you can check them. Observations from my own clinical and research experience are labeled From practice. My opinions and working hypotheses are labeled Editorial. Where the evidence is strong, I’ll say so plainly. Where I’m reasoning ahead of the data, I’ll say that too. The value I add is in deciding which findings belong next to each other.

I’m using that research as the spine of a series. Osteoporosis touches more than one system in the body, and it isn’t a conversation for a single visit.

Every series needs a starting point. The starting point has to be the most basic question, asked honestly: what is osteoporosis, actually?

The Short Version

Bone is living tissue. It is constantly broken down by one set of cells and rebuilt by another. In youth, building wins. Peak bone mass, the most bone you will ever have, arrives in your twenties. After that the equation slowly tips the other way, and when it tips far enough, bone becomes porous: literally “osteo” (bone) “porosis” (porous). Fracture risk climbs, especially at the hip, spine, and wrist.

How fast that happens varies enormously between people. Genetics, nutrition, body weight, physical activity, reproductive hormone status, tobacco and alcohol, medications such as prednisone, and chronic diseases such as diabetes or rheumatoid arthritis all shape both your peak bone mass and your subsequent rate of loss. Bone loss accelerates for about a decade after menopause. Some people fracture relatively young. Others keep robust bone well into later life.[1]

Most people know roughly that much. What almost nobody is told is how the decision gets made that you “have” it.

The Number That Runs the Whole System

The diagnosis hinges on a T-score from a DXA scan (dual-energy X-ray absorptiometry), a quick, low-radiation scan usually of the lower spine and hip. The T-score compares your bone density to that of a healthy young adult.

  • −1.0 or better: normal
  • Between −1.0 and −2.5: osteopenia (lower than ideal, not osteoporosis)
  • −2.5 or below: osteoporosis

The number is genuinely useful. Each step down that scale multiplies fracture risk. But it was never meant to be the whole definition, and the guidelines themselves say so. If you break a hip or a spinal bone from something that shouldn’t break a bone (a fall from standing, a cough, lifting a grocery bag) that is osteoporosis, whatever your T-score says. So is osteopenia combined with a fragility fracture of the shoulder, pelvis, or wrist, or osteopenia combined with a high score on FRAX, the Fracture Risk Assessment Tool, an online calculator that estimates your 10-year fracture probability from age, weight, fracture history, smoking, steroid use, and related factors. FRAX is the most widely validated fracture prediction tool in the world, with versions for more than 70 countries.[7]

For many people, the first sign of osteoporosis is the fracture. A broken wrist, shoulder, pelvis, or hip after a minor fall is often the late-stage manifestation of a silent, continuous process that a scan could have detected years earlier.[1]

Bone can already be failing while the number still reads “not quite.” Bone can already be failing while the number still reads ‘not quite.’

Myth #1: If Nobody Has Flagged You, Your Bones Are Presumably Fine

 

This is the one I want to spend the most time on. It shapes an entire lifetime of decisions.

In the United States, routine screening is recommended for women 65 and older, and for postmenopausal women under 65 whose risk assessment says they need it earlier, according to the U.S. Preventive Services Task Force.[2] The systematic evidence review behind that recommendation looked specifically at what’s known about screening benefit and harm across age groups.[3] For men, the Task Force concluded the evidence is insufficient to say whether screening helps. That means unknown, not “don’t bother.”[2]

So for most women without a flagged risk factor, the first bone density scan of their life happens somewhere in their mid-sixties. Roughly four decades after peak bone mass was set.

Here’s the assumption buried in that timeline: that whatever number shows up at 65 represents decline from a healthy starting point. Without a baseline, there is no way to know that.

A woman gets her first scan, sees a lower number than she’d like, and reasonably concludes she has been losing bone. Maybe. Or maybe she never built adequate bone density in the first place, and 65 is simply the first time anyone looked.

From practice. In the research I worked on, we scanned people across a far wider age range than screening protocols contemplate: teenagers, people in their twenties. A meaningful number of those young people had never reached what would be considered an ideal density range to begin with. Their bone density was never built at that level. That observation comes from that cohort specifically, and it’s the reason I started asking the question in the first place.

Editorial: why isn’t a baseline standard? My read is that screening programs exist largely to identify people who would benefit from prescription drug therapy, and there is no established, reimbursable drug treatment for a 25-year-old with below-ideal bone density. Medicine tends to build screening around what it is prepared to do with the result. The system is structurally blind to the half of the problem you can still do something about. That gap is a design choice, not an oversight.

I want to be fair about it too. That logic isn’t corrupt, and no one has shown that mass-scanning healthy 25-year-olds prevents fractures. But fair doesn’t mean the blind spot goes away. Peak bone mass is set by your twenties, and everything after that is management of a declining asset. The window that matters most gets skipped entirely.[1]

If you are a parent, an athlete, someone with a history of disordered eating, someone who lost their period for a stretch, someone on long-term steroids, or someone with a family history of fractures or early osteoporosis, this is the myth to retire first. Knowing your starting point is not the same as being sick. It is information you can act on with food, weight-bearing loading, resistance training, vitamin D, and sleep, none of which require a prescription.

Myth #2: A Fracture Is a Bad Week, and Then You Heal

This is where osteoporosis stops being an abstraction about numbers.

Spine fractures: the ones you don’t notice. Vertebral fractures are the most common manifestation of osteoporosis, accounting for an estimated 700,000 of the 1.5 million osteoporotic fractures occurring annually in the United States. Two-thirds are undiagnosed or found incidentally, and only about a quarter to a third of them are recognized clinically when they happen. In people with osteoporosis, most result from ordinary behaviors: lifting light objects, sneezing, coughing, even turning over in bed.[4,5]

That silence is the problem. A spine fracture is not a self-contained event. It sets a cascade in motion.

It predicts the next one. A vertebral fracture raises the risk of subsequent hip and other fractures, and that increase is only partly explained by the lower bone density of the people who have them, which is precisely why its presence should change treatment decisions.[4] It also changes your shape permanently. Lost vertebral height doesn’t come back. The forward tipping becomes fixed, and each degree of forward tipping loads the front of the next vertebra a little harder.

From there, the world tends to shrink. The documented long-term consequences follow mainly from decreased mobility: chronic back pain, height loss and kyphosis, difficulty sleeping, reduced physical activity with subsequent muscular atrophy, more fractures, and continued loss of bone density. Decreased respiratory function is on that list too.[5]

There is a real mortality and dependency cost to all of it. After compression fracture, older women have increased nursing home admission rates and an annual mortality rate of up to 15%. Some of that reflects the frailty that produced the fracture rather than the fracture itself, but the trajectory is what matters to the person living it.[4,5]

A spine fracture tips the scale toward more bone loss, less movement, less muscle, and the next fracture. Less activity means less loading. Less loading means less bone. The fracture makes the disease that caused it worse.

Hip fracture: a different category. A hip fracture changes the trajectory of a life.

The numbers are stark. Worldwide, the median one-year mortality after hip fracture is 22%. In the U.S. between 2008 and 2017, one-year mortality was 26.9% in men and 18.5% in women. About 20% require long-term nursing facility care. About 25% sustain another fracture within the following year. Only 42% to 71% get back to their prior level of basic daily activities (dressing, bathing, walking) by six months. The average age at hip fracture is 81.[6]

Those are people who were, in most cases, managing their own lives the week before.

Editorial. That contrast is the whole reason I write about the spine the way I do. The vertebral fracture is the loud early warning for the quiet catastrophe that comes later, and it is the warning that most often goes unread. Two-thirds of them are never diagnosed at all.[5]

What About the Scan Itself?

This deserves its own post, so I’ll only outline it here.

The lumbar spine “score” on your report is not one measurement. It is an average, usually of four separate vertebrae measured individually and blended into one figure. Averaging is a reasonable engineering decision, and the guidelines contain real safeguards for when a level should be thrown out of the average. But averaging always costs information.

There is also a second image the same machine can capture in the same visit: vertebral fracture assessment, a side view of the spine used specifically to find those silent compression fractures. It uses far less radiation than a standard spine X-ray, has good sensitivity for moderate and severe fractures, predicts future fractures even after accounting for age and bone density, and is cost-effective. It appears in screening guidelines. It is still frequently not ordered.[7]

Editorial. How your result is actually produced, what gets averaged away, what that side image shows, and how all of it intersects with posture, alignment, and the structural integrity of the whole neuromuscular system is a full technical piece, and it’s coming. For now, the useful takeaway for a patient is smaller: ask to see your report, not just your score, and ask whether the spine images were reviewed.

Why This Isn’t Only About Bones

I was in the room for this part.

Our research wasn’t studying bone density in isolation. We were asking whether parathyroid hormone, a small gland’s regulator of calcium, was connected both to bone loss and to something happening upstream in the brain. In a study I co-authored, patients with higher parathyroid hormone had lower bone density and slower P300 latency, a measure of cognitive processing speed, than patients with lower levels.[8] I examined the patients behind those numbers myself, which is part of why this finding has stayed with me longer than most.

Bone and brain, correlated in the same patients, on the same day, from the same blood draw and the same scan.

Editorial. That’s a correlation in one group of people, not a proven cause, and I’ll treat it that way throughout the series. But it reframes the category. Osteoporosis was never purely a skeletal condition. It sits inside hormonal regulation: parathyroid, thyroid, vitamin D, calcium, sex hormones. And hormonal regulation doesn’t stop at the skeleton. It touches sleep. It touches cognition. It touches mood.

Where We’re Headed

This post is the foundation: what osteoporosis is, why waiting until 65 to look for the first time hides half the problem, and why a fracture is a turning point rather than an episode.

From here: the hormonal drivers of bone loss, a full walk-through of what a bone density report actually shows and what it averages away, posture and rounded upper back as something that may come before fracture rather than only after it, muscle as a measurable and largely ignored part of fracture risk, and the bone-brain connection the research pointed toward.

This post is the foundation: two osteoporosis myths worth retiring, why waiting until 65 to look for the first time hides half the problem, and why a fracture is a turning point rather than an episode.

References

  1. Ye C, Ebeling P, Kline G. Osteoporosis. Lancet. 2025;406(10514):1735-1748.
  2. US Preventive Services Task Force, Nicholson WK, Silverstein M, et al. Screening for Osteoporosis to Prevent Fractures: US Preventive Services Task Force Recommendation Statement. JAMA. 2025;333(6):498-508.
  3. Kahwati LC, Kistler CE, Booth G, et al. Screening for Osteoporosis to Prevent Fractures: A Systematic Evidence Review for the US Preventive Services Task Force. JAMA. 2025;333(6):509-523.
  4. Ensrud KE, Schousboe JT. Vertebral Fractures. N Engl J Med. 2011;364(17):1634-1642.
  5. Creech-Organ J, Organ B. Vertebral Compression Fractures. Am Fam Physician. 2026.
  6. Johannesdottir F, Roberts JE, Kiel DP, et al. Hip Fractures. JAMA. 2026.
  7. Ye C, Leslie WD, Morin SN, et al. Adjusting FRAX Estimates of Fracture Probability Based on a Positive Vertebral Fracture Assessment. JAMA Netw Open. 2023;6(7):e2323725.
  8. Braverman ER, Chen TJH, Chen ALC, Arcuri V, Kerner MM, Bajaj A, Carbajal J, Braverman D, Downs BW, Blum K. Age-Related Increases in Parathyroid Hormone May Be Antecedent to Both Osteoporosis and Dementia. BMC Endocr Disord. 2009;9:21. doi:10.1186/1472-6823-9-21.

Ready to understand what your spine and posture are telling you?
Dr. Bajaj sees patients in Westfield, NJ and New York City. Every new patient relationship begins with a comprehensive physical exam, an honest look at how your body is functioning and where it needs support.
Request an Appointment: https://wellrootedhealth.clientsecure.me
Call NJ: 908-588-7532 · NY: 212-655-5802 Email: info@gowellrooted.com