Bone starts thinning before the last period, which makes midlife the time to act

Key takeaways

• In a federally funded study of U.S. women, a scan-based measure of spine bone quality began falling about 1.5 years before the final period, then dropped about 1.16% a year⁴.
• Since January 2025, the U.S. Preventive Services Task Force has advised a bone density test for all women 65 and older, and for younger women past menopause when a risk check shows higher risk².
• In three large trials, screening older women prevented about 5 hip fractures for every 1,000 screened over four to five years².
• In the Women’s Health Initiative trial, 8.6% of women taking estrogen plus a progestin broke a bone over about 5.6 years, compared with 11.1% on placebo⁷.
• Strontium in some bone supplements makes a bone density scan read higher than the bone really is, and the effect may last for years after you stop¹.

A friend hugged a 61-year-old woman a little too tightly, and her breastbone broke. Two University of Pennsylvania doctors described her case in a short report at a 2021 hospital medicine meeting¹.

Her bone density scan showed osteoporosis in her spine, with a T-score of −3.5¹. A T-score compares your bone density with a healthy young adult’s, and a score of −2.5 or lower at the hip or spine is in the osteoporosis range².

Under today’s Task Force rules, routine scans for every woman start at 65². Before that, the Task Force advises a scan for a woman her age when a risk check flags her².

Her story took a strange turn later. But the first part holds the lesson: bone can thin a lot before 65, much of it in a short window around the last period. Muscle slips in the same years, which makes your late 40s and 50s the best time to act.

Bone loss starts before the last period, then runs fast for a few years

The Study of Women’s Health Across the Nation, or SWAN, a National Institutes of Health project, has followed U.S. women from before menopause into the years after it⁴⁵.

Bone turnover, the constant breakdown and rebuilding of bone, speeds up about two years before the final period and levels off about 1.5 years after it, a 2025 paper summarizing that work notes³. Density drops fastest at the spine and the femoral neck, the top of the thighbone at the hip, in a window that opens about a year before the last period and runs until two years after³.

In some women, density falls by more than one full T-score unit over the four years around the final period, SWAN researchers wrote in 2023⁵.

Bone quality changes, too. In a 2020 SWAN analysis of 705 Black, Japanese and White women, researchers tracked the trabecular bone score, a DXA-based measure of the spine’s inner lattice⁴. It held steady until about 1.5 years before the last period, then fell 1.16% a year⁴. Starting two years after, the decline slowed to 0.89% a year⁴.

Over the 10 years around the last period, the score fell 6.3% for a typical White woman and 4.9% for Black women⁴.

The losses add up. In an Australian study published in 2025, among women not using hormone therapy, 37.4% had low hip bone mass within five years of menopause³. The share was 45.3% at five to 10 years and 63.9% after 10³. By our math, that’s nearly 2 in 3 women a decade out.

Women using hormone therapy lost less bone at most sites, though the study was observational³.

Muscle slips in the same window, and it may matter for fractures

In a 2023 SWAN report, researchers measured the body composition of 539 women from two years before the final period to two years after⁵. Lean mass, which is mostly muscle, dipped less than 1% on average, but some women lost far more⁵.

Women who lost more lean mass tended to end that stretch with lower density at the femoral neck⁵. Over the next 14.6 years on average, 64 of the 539 women broke a bone, about 1 in 8 by our math⁵.

For each additional 6.9% of lean mass lost, fracture risk was 63% higher, even after accounting for bone density⁵. The study was observational, and the authors reported no conflicts⁵. It suggests muscle deserves the same midlife attention as bone.

Estrogen may matter for muscle as well. Finnish researchers studied 15 pairs of identical twin sisters aged 54 to 62⁶. In each pair, one twin had used hormone therapy for about seven years on average and the other hadn’t⁶. Identical twins share their genes, which helps rule out inherited differences.

The twins on hormones walked 7% faster at top speed and had about 8% more thigh muscle relative to thigh size⁶. They also jumped about 16% higher, a test of muscle power, though that result was borderline: its margin of error stretched down to no difference at all⁶. Grip and knee strength didn’t differ⁶.

Fifteen pairs is tiny, and a snapshot isn’t a trial, so treat this as an early clue⁶. Our muscle articles cover strength tests and protein needs.

The Task Force’s two-step test for women under 65

The U.S. Preventive Services Task Force is an independent panel of prevention experts. Its January 14, 2025 update covers adults 40 and older who haven’t been diagnosed with osteoporosis or had a fragility fracture, a break caused by falling from standing height or less².

• Women 65 and older: get a bone density test, usually a DXA scan of the hip and spine (grade B)².
• Women past menopause who are younger than 65: get screened if they’re at increased risk (grade B)².
• Men: the evidence is insufficient to recommend for or against (an “I” statement)².

For younger women, the Task Force spells out two steps². First, check for risk factors: low body weight, a parent who broke a hip, smoking, or drinking too much alcohol. Steroid medicines and diabetes treated with insulin may also raise risk².

Second, a woman with at least one risk factor gets a risk tool, such as FRAX, OST or ORAI. A scan follows if the tool shows higher risk². The Task Force set no FRAX cutoff².

In three European trials of more than 42,000 women whose median age was 71 to 76, screening meant 5 fewer hip fractures per 1,000 women over 3.7 to 5 years². By our math, that’s 1 hip fracture prevented for every 200 women screened. Harms looked small: in one trial, screened women were no more anxious than others².

Most fragility fractures happen in people whose T-scores are above the osteoporosis line, the Task Force notes². That’s why risk factors count, too.

Guideline groups don’t agree. In 2023, the Canadian Task Force on Preventive Health Care recommended against screening women under 65². In 2020, the American Association of Clinical Endocrinologists said all women 50 and older should have their fracture risk evaluated².

Race adds a wrinkle. Race-specific versions of FRAX always give Asian, Black and Hispanic people lower estimates than White people with the same inputs, which the Task Force warned could lead to unequal treatment offers².

After a first scan, timing depends on the result. In studies the Task Force reviewed, it took almost 17 years for 1 in 10 women with normal density to develop osteoporosis, versus about 5 years for women whose T-scores started at −1.50 to −1.99².

Men’s bones age too, with less evidence to guide them

Among U.S. adults aged 50 to 64, 3.3% of men had osteoporosis, compared with 13.1% of women². By our math, that’s about 1 man in 30 versus 1 woman in 8.

No trial has tested screening men, which is why the Task Force gave an “I” grade rather than advice against it².

In 1,199 men with low bone density, zoledronic acid, a bone drug given by IV, cut new spine fractures seen on X-rays from 4.6% to 1.5%². By our math, that’s about 31 fewer per 1,000 men. Other fractures didn’t fall significantly².

After a fragility fracture, the extra risk of death is greater for men than for women, the Task Force notes². Some groups advise scanning men over 70². Our estrogen and testosterone articles cover how both hormones matter for men’s bones.

Hormone therapy protects bone while you take it

Estrogen’s effect on bone was tested in the Women’s Health Initiative (WHI), a large U.S. trial. In the arm reported in JAMA in 2003, 16,608 women aged 50 to 79 with a uterus took estrogen plus a progestin or a placebo for about 5.6 years⁷. Their average age was 63⁷.

Outcome	Hormones	Placebo	By our math
Hip fractures per 10,000 women a year	11	16	5 fewer per 10,000 women each year
Women with any fracture	8.6%	11.1%	About 1 fewer woman with a fracture for every 40 treated
Change in hip bone density at 3 years	+3.7%	+0.14%	A gain on hormones, almost none on placebo

Source: WHI fracture report⁷.

The fracture benefit appeared whether women’s starting risk was high or low⁷. But in 2003 the authors concluded it didn’t outweigh the trial’s other risks overall, even for women at high fracture risk⁷. A 2013 follow-up of 27,347 women in both WHI hormone trials found that most benefits and risks faded after women stopped⁸. Those authors said hormone therapy suits symptom relief for some women, but not chronic disease prevention⁸.

The FDA counts estrogen, with or without a progestin, among the medicines approved to treat or prevent osteoporosis². Hormone therapy labels began changing in February 2026, as our menopause sleep article explains.

For bone, hormone therapy helps while you use it. Whether it fits you depends on your symptoms, age and history, a choice to make with a clinician. If your fracture risk is already high, our bone medicine article counts what each drug does.

A supplement can make your scan look better than your bones

Back to the woman with the broken breastbone. She declined the usual osteoporosis medicines and worked with an integrative medicine doctor, taking calcium, vitamin D and other supplements¹.

Three years later, her spine T-score had climbed to −1.6, and both hip numbers were normal¹. Her doctors reported gains of 31.7% at the spine and 20% at the hip¹.

Too remarkable. One of her supplements contained 680 mg of elemental strontium¹. Strontium is a mineral that settles into bone and blocks X-rays more than calcium does, so a DXA scan reads the bone as denser than it is¹. The authors wrote that the false boost may last up to 10 years after someone stops, and urged doctors to ask about strontium when density jumps fast¹.

Strontium also has a drug history. A prescription form, strontium ranelate, marketed in Europe as Protelos and Osseor, was authorized there to reduce spine and hip fractures⁹.

But in pooled trials of about 7,500 women, 1.7% on the drug had heart attacks, compared with 1.1% on placebo⁹. By our math, that’s about 6 extra per 1,000 women. Blood clots affected 1.9% versus 1.3%⁹.

In February 2014, the European Medicines Agency’s drug committee recommended limiting it to people with severe osteoporosis who can’t use other medicines⁹. It also recommended barring it for anyone with past or current heart or circulation disease or uncontrolled high blood pressure⁹. The agency’s safety committee had wanted it suspended outright⁹.

Protelos and Osseor are no longer authorized in the European Union. In April 2020, the European Commission withdrew both at the request of their maker, Servier, which cited commercial reasons¹⁰.

Strontium isn’t among the FDA-approved osteoporosis drugs the Task Force lists². The European fracture data came from the prescription compound and say nothing about a store-bought supplement. What a supplement clearly can do is cloud the scan you rely on. Our collagen and creatine articles cover two other products sold for bone and muscle.

The midlife bone and muscle plan

We built this plan from the sources in this article. It hasn’t been tested as a package.

Step	What to do	What the evidence says	Source
1. List your risk factors	Note low body weight, a parent’s hip fracture, smoking, heavy drinking, steroid medicines or insulin-treated diabetes	The Task Force’s starting points for women under 65	2
2. Run a risk check	Try the weight-and-age check, or ask your clinician for FRAX	Tools decide who under 65 needs a scan	2
3. Get scanned on time	All women at 65; younger women past menopause if a tool flags them; men can ask about their own risk	Screening older women cut hip fractures; men’s evidence is thin	2
4. Load bone, build muscle	Heavier lifting and, if cleared, short bursts of impact on 2 or 3 days a week	Small trials raised bone density	Our bone-loading article
5. Feed bone and muscle	Protein foods at each meal; calcium from food first	Food sidesteps questions about calcium pills	Our protein and calcium articles
6. Ask about hormone therapy if you have symptoms	Weigh fracture protection against your own risks	Fewer fractures while used; benefit faded after stopping	78
7. Show your supplements	Tell your clinician and the scan center about any strontium	Strontium falsely raises DXA readings	1

Prevention is at the heart of natural health, and bone rewards it. The steps with the widest reach, working your muscles hard, eating real food and not smoking, need no prescription. A scan doesn’t betray that approach. Like a soil test, it tells you whether your habits are enough.

Talk with a clinician sooner if:

• You break a bone falling from standing height or lower. The Task Force’s screening advice is for people who haven’t had such a break².
• You take steroid medicines long term or have a condition, such as an overactive thyroid or cancer, that affects bone. The screening advice doesn’t cover you².
• A scan shows osteoporosis. The Task Force says such women need further evaluation and counseling².

What the evidence shows

Approach	Evidence level	What the research shows
Bone density screening for women 65 and older	Strong evidence	About 5 fewer hip fractures per 1,000 screened in three trials2
Screening women under 65 after a risk check prevents fractures	Promising but early	Task Force grade B, but the screening trials enrolled women in their 70s2
Routine screening for men	Not enough evidence	No screening trials in men2
Hormone therapy to prevent fractures	Strong evidence	Fewer hip and total fractures in a large trial; benefit faded after stopping78
Hormone therapy to preserve muscle power	Promising but early	One small twin study; strength tests didn’t differ6
Prescription strontium ranelate as a routine bone drug	Evidence says no, or unsafe	Prevented fractures but raised heart attack and clot risk; tight limits recommended in Europe in 20149
Strontium supplements	Not enough evidence	We found no fracture trials of store-bought strontium, and it inflates scan results1

Questions readers ask

The bottom line

Bone loss doesn’t wait for 65. It speeds up in the years around the last period, and muscle slips at the same time. For women under 65, the 2025 Task Force rules start with a simple risk check, and a scan follows when the check shows higher risk.

What protects you is a mix: strong muscles, real food, no smoking, a scan when it’s due, and medicine or hormone therapy when your risk or symptoms call for it. Be wary of any supplement that promises dramatic scan gains. A better number isn’t always a stronger bone.

Related reading

• Heavy lifts and jumps build bone in ways walking alone mostly doesn’t
• The real odds after a broken hip, when few people get bone medicine
• Scanned muscle mass failed a major health test that strength and walking speed passed
• Calcium Pills Have Raised Heart Questions Since 2010. Food Calcium Hasn’t
• One man’s bones proved estrogen matters for men as well as women

Sources

1. Dharia T, Christensen K (University of Pennsylvania). “Strontium: Not All It’s Cracked Up to Be.” Clinical vignette, SHM Converge 2021, Abstract 405. Society of Hospital Medicine abstracts, 2021. shmabstracts.org
2. U.S. Preventive Services Task Force. “Osteoporosis to Prevent Fractures: Screening.” Final recommendation statement, January 14, 2025 (published in JAMA, 2025;333(6):498–508). uspreventiveservicestaskforce.org
3. Holloway-Kew KL, et al. “Patterns of Bone Mineral Density Loss at Multiple Skeletal Sites Following Recent Menopause in Users and Non-Users of Menopausal Hormone Therapy.” Calcified Tissue International, 2025;116:80. link.springer.com
4. Cauley JA, Finkelstein JS, Greendale GA, et al. “Trabecular Bone Score Declines During the Menopause Transition: The Study of Women’s Health Across the Nation (SWAN).” 2020;105 (CDC Stacks record). stacks.cdc.gov
5. Shieh A, Karlamangla AS, Karvonen-Gutierrez CA, Greendale GA. “Menopause-Related Changes in Body Composition Are Associated With Subsequent Bone Mineral Density and Fractures: Study of Women’s Health Across the Nation.” Journal of Bone and Mineral Research, 2023;38(3):395–402. pubmed.ncbi.nlm.nih.gov
6. Ronkainen PHA, Kovanen V, Alén M, et al. “Postmenopausal hormone replacement therapy modifies skeletal muscle composition and function: a study with monozygotic twin pairs.” Journal of Applied Physiology, 2009;107(1):25–33 (University of Jyväskylä repository record). jyx.jyu.fi
7. Cauley JA, Robbins J, Chen Z, et al. “Effects of Estrogen Plus Progestin on Risk of Fracture and Bone Mineral Density: The Women’s Health Initiative Randomized Trial.” JAMA, 2003;290(13):1729–1738. pubmed.ncbi.nlm.nih.gov
8. Manson JE, et al. “Menopausal Hormone Therapy and Health Outcomes During the Intervention and Extended Poststopping Phases of the Women’s Health Initiative Randomized Trials.” JAMA, 2013;310(13):1353–1368. pubmed.ncbi.nlm.nih.gov
9. European Medicines Agency. “European Medicines Agency recommends that Protelos/Osseor remain available but with further restrictions.” Press release, February 21, 2014. ema.europa.eu
10. European Medicines Agency. “Public statement on Protelos: Withdrawal of the marketing authorisation in the European Union” and the matching statement on Osseor. May 4, 2020. ema.europa.eu and ema.europa.eu