Evidence reviewBone & muscleEvidence Tier I

How Does Osteoporosis Develop and What Are the Most Effective Prevention Strategies?

Osteoporosis develops through an imbalance between bone formation and resorption, accelerated by oestrogen loss, vitamin D deficiency, and physical inactivity — but is largely preventable through weight-bearing exercise, adequate calcium and vitamin D, and fall prevention.

Dr. Amelia Stone, MD, Endocrinology
May 21, 2026
2 min read

The short answer

Osteoporosis affects approximately 200 million people worldwide and is the leading cause of fragility fractures in older adults. It develops when bone resorption outpaces bone formation — a process accelerated by oestrogen loss at menopause, vitamin D deficiency, physical inactivity, and smoking. Hip fractures in particular are associated with a 20–30% mortality rate within one year.

What the evidence actually shows

The NIA notes that osteoporosis is a condition in which bones become weak and brittle, increasing the risk of fractures. Bone density peaks in the late 20s and declines thereafter, with accelerated loss in women after menopause. A 2016 meta-analysis by Weaver et al. in Osteoporosis International found that calcium supplementation (1,000–1,200 mg/day) combined with vitamin D (800 IU/day) reduced hip fracture risk by 16% and total fracture risk by 8% in older adults. A 2017 meta-analysis by Zhao et al. in JAMA Internal Medicine found that resistance training increased bone mineral density at the spine by 1.03% and at the hip by 0.68% — modest but clinically meaningful effects.

"Calcium and vitamin D supplementation reduced hip fracture risk by 16% in older adults."

Weaver et al., Osteoporosis International 2016

What the major health authorities say

The NIA recommends adequate calcium (1,000–1,200 mg/day for adults over 50) and vitamin D (800–1,000 IU/day), weight-bearing exercise, and fall prevention as the primary strategies for osteoporosis prevention. MedlinePlus identifies osteoporosis as a major public health concern and notes that it is often called a 'silent disease' because bone loss occurs without symptoms until a fracture occurs. DEXA scanning is recommended for all women over 65 and men over 70, and earlier for those with risk factors.

Practical implications

The most impactful osteoporosis prevention strategies are: weight-bearing exercise (walking, jogging, dancing, resistance training) which directly stimulates bone formation; adequate calcium from food sources (dairy, fortified plant milks, leafy greens, tinned fish with bones); vitamin D supplementation (800–1,000 IU/day for most adults over 65); and avoiding smoking and excessive alcohol. For individuals with established osteoporosis (T-score ≤ −2.5 on DEXA), pharmacological treatment with bisphosphonates (alendronate, risedronate) reduces fracture risk by 40–50%.

Vitaei verdict

Osteoporosis is largely preventable with weight-bearing exercise, adequate calcium and vitamin D, and fall prevention. DEXA screening identifies those who need pharmacological treatment.

Where reasonable people still disagree

  • Whether calcium supplementation (as opposed to dietary calcium) increases cardiovascular risk — a concern raised by some meta-analyses but not confirmed in others.
  • The optimal duration of bisphosphonate therapy and whether drug holidays are appropriate after 3–5 years of treatment.
  • Whether vitamin K2 supplementation provides meaningful additional benefit for bone health beyond calcium and vitamin D.