Osteoporosis Risk Factors

The Scale of the Problem in Canada

According to Osteoporosis Canada, over 2.3 million Canadians are currently living with osteoporosis. Public Health Agency of Canada data from 2015–2016 found that approximately 11.9% of Canadians aged 40 and older had diagnosed osteoporosis — about 80% of them women. That's the diagnosed number. The actual prevalence is higher, because many Canadians don't get screened until after a fracture.

Osteoporosis Canada reports that over 80% of all fractures in people aged 50+ are caused by osteoporosis. And yet most people receive no bone density assessment until they've already broken something. A hip fracture from a fall, a vertebral compression fracture from a minor stumble — these are often the first sign that bone loss has been underway for years.

The case for understanding your personal risk profile is simple: the interventions available before significant bone loss — lifestyle, nutrition, exercise, monitoring — are far more effective than those after. Risk awareness drives earlier screening and earlier action.

Non-Modifiable Risk Factors

These are the factors you were born with or that come with age. You can't change them. But knowing they apply to you should prompt earlier conversation with your GP about screening and prevention.

Age

Bone density peaks in the late twenties and early thirties, then holds roughly stable until the mid-forties. After that, gradual loss begins. In women, menopause accelerates this dramatically — up to 3–5% bone loss per year in the first 5–10 years post-menopause. Men lose bone more slowly but the decline is still real, particularly after 70. By 80, fracture risk is substantial for both sexes regardless of other factors.

Sex

Women face significantly higher osteoporosis risk than men, for two reasons. First, women generally have smaller, less dense bones to begin with. Second — and more important — estrogen is powerfully protective for bone, and its sharp decline at menopause removes that protection suddenly. Men have testosterone, which also helps maintain bone mass, but they don't experience a sudden hormonal shift equivalent to menopause. About 80% of the 2.3 million Canadians with osteoporosis are women.

Family History

A parent who had a hip fracture roughly doubles your own hip fracture risk, independent of bone density. This is so consistent that family history of hip fracture is a direct input in both the FRAX and CAROC fracture risk calculators. Genetics influence peak bone mass, bone architecture, and rate of bone loss — all of which are heritable to meaningful degrees.

If your mother or father broke a hip (particularly from a low-impact fall rather than a car accident), bring that up with your GP. It's a specific, actionable piece of information.

Ethnicity and Fracture Risk

This is an area where the data is real but complex, and worth understanding carefully. Caucasian and Asian women have higher rates of osteoporotic fracture than Black and Hispanic women at comparable bone density scores — partly because of differences in bone geometry (not just density), vitamin D metabolism, and muscle mass. The FRAX tool has been calibrated separately for Canadian populations using Canadian fracture data, which accounts for some of these differences.

Practically: if you're of South Asian, East Asian, or Caucasian heritage and have other risk factors, osteoporosis risk is something to take seriously relatively early. But no ethnic group is immune — osteoporosis occurs across all populations.

Early Menopause

Menopause before age 45 — whether natural or surgical (oophorectomy) — significantly accelerates bone loss by cutting off estrogen protection earlier in life. The earlier menopause occurs, the more bone loss can accumulate before the typical screening age of 65. Women with premature or early menopause should discuss bone density screening well before they hit the standard eligibility criteria.

Hypogonadism in Men

Low testosterone in men — whether from primary hypogonadism, pituitary disorders, or treatments like androgen deprivation therapy (used for prostate cancer) — causes bone loss through the same mechanism as estrogen loss in women. Men on long-term androgen deprivation therapy have substantially elevated fracture risk and should be on a bone protection strategy from the outset of treatment.

Prior Fragility Fracture

A fragility fracture — a fracture occurring from a fall from standing height or less, or from a mechanism that wouldn't break a healthy bone — is one of the strongest predictors of future fracture. The bone that broke is telling you something about the rest of your skeleton. Someone who's had a wrist fracture from a minor fall at age 55 has roughly twice the subsequent fracture risk of someone who hasn't. This is a major input in the FRAX calculator and should trigger bone density assessment at any age.

Modifiable Risk Factors

These are the factors within your control. Not all are equally impactful, and some (smoking, physical inactivity) matter far more than others (caffeine). But collectively, the modifiable factors represent the largest opportunity to change your trajectory.

Smoking

Smoking is one of the clearest modifiable risk factors for osteoporosis. The mechanisms are several: nicotine directly impairs osteoblast function, smoking reduces calcium absorption, it lowers estrogen levels in women, and it generally accelerates aging of multiple organ systems. The effect is dose-dependent — the more you smoke and the longer you've smoked, the greater the bone impact. Current smokers have meaningfully lower BMD than non-smokers; former smokers recover some of this deficit over time. There's no threshold below which smoking is safe for bone.

Heavy Alcohol Consumption

More than two standard drinks per day consistently, over time, impairs bone formation and reduces calcium absorption. Heavy drinkers also fall more frequently, compounding the fracture risk. The Osteoporosis Canada 2023 guidelines list alcohol consumption exceeding two drinks per day as a recognized risk factor. Moderate consumption (one drink/day for women, up to two for men) does not appear to significantly harm bone density, but heavy or binge drinking clearly does.

Physical Inactivity

Bone responds to mechanical load — remove the load and bone mass declines. Prolonged bed rest causes measurable bone loss within weeks. Sedentary lifestyles throughout adulthood result in lower peak bone mass and faster age-related decline. Weight-bearing exercise and resistance training are the most effective interventions for maintaining bone density at any age. See our bone density exercise program guide for specifics on what works and what doesn't.

Low Calcium Intake

Calcium is the primary mineral component of bone. Chronically inadequate calcium intake forces the body to draw calcium from the skeleton to maintain blood calcium levels — a process that happens continuously in the background of a low-calcium diet. The recommended intake is 1000 mg/day for most adults, rising to 1200 mg/day for women over 50 and men over 70. Many Canadians fall short, particularly those who avoid dairy or don't eat calcium-rich alternatives. See our calcium intake guide for food sources and supplementation guidance.

Vitamin D Deficiency

Vitamin D is essential for calcium absorption in the gut. Without adequate vitamin D, you can consume all the calcium in the world and still have impaired absorption. In Canada, this is structurally complicated by latitude: from roughly October to March, the sun angle is insufficient for skin vitamin D synthesis at any major Canadian city. Vitamin D deficiency is common among Canadians, particularly the elderly, people with darker skin tones, those who are rarely outdoors, and people in care facilities. The Osteoporosis Canada 2023 guidelines recommend minimum 400 IU supplemental vitamin D3 for adults over 50, with most clinicians recommending 800–2000 IU for those at bone health risk. See our vitamin D in Canada guide for full detail.

Low Body Weight

BMI below 20 is an independent risk factor for osteoporosis and fracture. Two mechanisms: low body weight means less mechanical load on the skeleton (bones don't build mass they don't need to support), and very low body weight is often associated with inadequate nutrition including calcium and protein. The FRAX calculator specifically incorporates body weight as an input.

Eating Disorders

Anorexia nervosa in particular causes severe bone loss, often irreversibly. The combination of severe caloric restriction, low estrogen (menstrual disruption is common), and nutritional deficiencies creates conditions for rapid bone mass loss at an age when bone should be accumulating. Many young women with a history of anorexia enter their thirties with the bone density of someone twenty years older. Bulimia can also impair bone health, though the effect is less severe than with anorexia. A history of eating disorder in early or middle life is a specific risk factor worth flagging to a physician.

Medications That Increase Osteoporosis Risk

This is the risk category most people aren't told about. Several commonly prescribed medications have documented negative effects on bone density. If you're on any of these long-term, you and your prescribing physician should have an explicit conversation about bone health monitoring.

Corticosteroids: The Most Important Category

Proton Pump Inhibitors (PPIs)

Some SSRIs (Antidepressants)

Aromatase Inhibitors

Other Medications Worth Noting

• Anticonvulsants (phenytoin, carbamazepine, valproic acid) — impair vitamin D metabolism, leading to secondary deficiency and bone loss with long-term use
• Androgen deprivation therapy (leuprolide/Lupron, bicalutamide) for prostate cancer — suppresses testosterone, causing bone loss equivalent to surgical castration in women
• Heparin (long-term use) — direct inhibition of osteoblast function; most relevant in prolonged anticoagulation scenarios
• Thiazolidinediones (pioglitazone, rosiglitazone) — older diabetes medications associated with increased fracture risk in women
• Medroxyprogesterone acetate (Depo-Provera contraceptive injection) — associated with bone density loss during use, though most is recovered after stopping

Secondary Causes of Osteoporosis

Secondary osteoporosis means bone loss driven by another medical condition rather than the primary aging process. These are often under-recognized because the underlying condition gets treated without attention to the bone consequences. Key secondary causes:

Celiac Disease and Inflammatory Bowel Disease

Any condition that impairs absorption in the small intestine compromises calcium and vitamin D absorption even when dietary intake is adequate. Celiac disease (gluten intolerance causing intestinal inflammation) and inflammatory bowel disease — particularly Crohn's disease, which can affect the duodenum where calcium absorption primarily occurs — both cause secondary osteoporosis. Undiagnosed celiac is particularly important: some patients present with osteoporosis as the first identified consequence of a condition they didn't know they had. Screening for celiac with a simple blood test (anti-tTG antibody) is warranted in anyone with unexplained low bone density.

Rheumatoid Arthritis

Rheumatoid arthritis increases osteoporosis risk through two routes. First, the chronic inflammatory state itself — elevated inflammatory cytokines accelerate osteoclast activity (bone resorption). Second, most RA patients are prescribed corticosteroids at some point, adding medication-related risk on top of the disease-related risk. RA patients should have active bone health monitoring as part of their rheumatology care.

Chronic Kidney Disease

The kidneys activate vitamin D (converting it from its storage form to its active hormonal form). In chronic kidney disease (CKD stages 3–5), this activation is impaired, leading to vitamin D deficiency and secondary hyperparathyroidism — a condition where the parathyroid glands over-produce PTH in an attempt to raise blood calcium, which they do by pulling calcium out of bone. The bone disease of CKD (renal osteodystrophy) is distinct enough from age-related osteoporosis that it's managed differently and requires nephrologist involvement.

Hyperthyroidism

Excess thyroid hormone accelerates bone remodeling — both formation and resorption — with resorption winning out at high levels. People with untreated hyperthyroidism (Graves' disease, thyroid adenoma) lose bone at an elevated rate. Importantly, over-treated hypothyroidism — where levothyroxine (Synthroid) dose is too high — has a similar effect, since that's essentially induced hyperthyroidism. TSH suppressed below the normal range on thyroid hormone replacement carries bone risk. Annual TSH monitoring while on thyroid medication is standard care, partly for this reason.

Other Conditions

• Primary hyperparathyroidism — elevated PTH from parathyroid gland overactivity draws calcium continuously from bone; often discovered incidentally on bloodwork
• Type 1 diabetes — associated with lower bone density, possibly through effects on osteoblast function
• Multiple myeloma and other bone marrow disorders — direct destruction of bone by malignant cells
• Chronic liver disease — impairs vitamin D storage and metabolism
• Premature ovarian insufficiency — estrogen deficiency before 40 with long consequences for bone

The FRAX Score: How Canadian Physicians Assess Fracture Risk

Bone density (T-score from a DEXA scan) tells you one thing: how dense your bones are relative to a young adult reference. It doesn't tell you the full fracture risk picture, because other factors matter too — your age, your prior fracture history, your medications, your family history. A 50-year-old and an 80-year-old with the same T-score have very different fracture risks. Enter FRAX.

What FRAX Is

FRAX (Fracture Risk Assessment Tool) is a WHO-developed tool that calculates your 10-year probability of a major osteoporotic fracture (hip, spine, wrist, or shoulder) based on a combination of clinical risk factors, with or without bone density data. It was developed using fracture data from multiple countries and has been calibrated for Canada specifically using Canadian fracture epidemiology data.

FRAX inputs include: age, sex, body weight, height, prior fragility fracture, parent hip fracture, current smoking, glucocorticoid use, rheumatoid arthritis, secondary osteoporosis, alcohol consumption, and optionally, femoral neck T-score from DEXA. The output is a percentage — for example, "this person has a 15% probability of a major fracture in the next 10 years."

CAROC: The Canadian Alternative

The Canadian Association of Radiologists and Osteoporosis Canada (CAROC) tool is a simpler Canadian-specific tool that categorizes fracture risk as low, moderate, or high based on age, sex, femoral neck T-score, and a few key risk factors (prior fragility fracture, glucocorticoid use). It produces a risk category rather than a percentage, and is integrated into many Canadian radiology reports when a DEXA scan is performed.

Both tools are calibrated to Canadian fracture rates and both are considered valid by the 2023 Osteoporosis Canada guidelines. Which one a physician uses depends partly on personal preference, partly on what's embedded in local clinical workflows.

How Canadian Physicians Use FRAX

The 2023 Osteoporosis Canada guidelines recommend fracture risk assessment for all adults over 50 using either FRAX or CAROC, with the result guiding decisions about who needs DEXA, who needs pharmacological treatment, and who can be managed with lifestyle measures alone.

• Low risk (FRAX <10% for major fracture): Lifestyle guidance, reassess in 5 years
• Moderate risk (FRAX 10–20%): Consider DEXA if not already done; pharmacological treatment may be warranted depending on other factors
• High risk (FRAX >20%, or hip fracture probability >3%): Pharmacological treatment generally recommended; DEXA to baseline and monitor response

You can run your own FRAX estimate at the WHO's FRAX tool at sheffield.ac.uk/FRAX (select Canada). It's a useful conversation-starter with your GP, not a replacement for clinical judgment.

What to Do With This Information

Reading through a risk factor list is useful precisely because it's actionable. A few practical steps:

Further Reading on This Site

• DEXA Scan in Canada: Coverage, Criteria, and Interpreting Your Results
• Bone Density Exercise Program: What to Do and How
• Osteoporosis Prevention in Canada: Full Guide
• Calcium Intake Guide for Canadians
• Vitamin D in Canadian Winter: Why Deficiency Is Common and What to Do
• Bone Health Over 50: What Changes and What Helps
• Bone Density Test in Canada: What to Expect