Bone mineral density (BMD) scanning using dual-energy X-ray absorptiometry (DXA, commonly referred to as DEXA) scanning is big business. Around the world, hundreds of millions of older women (and many men too), on the basis of their scan results, are prescribed potent drugs including bisphosphonates (Fosamax, Actonel, Reclast) and monoclonal antibodies (Prolia, Evenity), that come with a laundry list of adverse effects.
But bone density testing has been repeatedly demonstrated to be next to useless at predicting an individual’s risk of fracture.
Here’s what the British Columbia Office of Health Technology Assessment had to say, in their review of the evidence for the effectiveness of BMD testing:
“Research evidence does not support either whole population or selective bone mineral density (BMD) testing of well women at or near menopause as a means to predict future fractures.”
Does Evidence Support the Selective Use of Bone Mineral Density Testing in Well Women?
The Swedish Council on Technology Assessment in Health Care reached the same conclusion:
“There is no scientific evidence to support the use of bone density measurement as a screening method in healthy, middle-aged individuals.”
Osteoporosis-prevention, diagnosis and treatment. A systematic literature review
The UK’s National Institute for Health and Care Excellence (NICE – how terribly British) recommends against routine measurement of bone mineral density for screening purposes. Instead, NICE recommends that practitioners “consider referring for BMD [measurement] with DXA”, only after a clinical risk factor assessment tool – either FRAX or QFracture – has indicated heightened risk of fracture.
NICE points out that
“Currently, there are no definitive studies in primary or secondary care evaluating whether the addition of BMD to FRAX improves the accuracy of the predicted fracture risk.”
But in the face of widespread scientific agreement that BMD scanning is NOT an effective screening tool (that is, a tool for assessing the future risk of fractures in a person who has not yet had a low-trauma fracture i.e. breaking a bone in circumstances where it wouldn’t be expected to break) it is still heavily promoted.
Most of my post-menopausal clients – no matter how fit, strong and active they are, and despite never having had a low-trauma fracture – have been urged by their doctors to have a ‘baseline’ BMD scan. This use of BMD scanning is exactly what all the government bodies quoted above advise against: screening of healthy, asymptomatic individuals.
As a result of this initial scan, a number of my clients have been told they have ‘osteopaenia’1, are at increased risk of bone fracture in the future, and should immediately start taking calcium pills and consider taking bisphosphonate drugs or monoclonal antibodies.
I have taken many calls from clients who previously thought of themselves as healthy and strong, and are now in tears as they describe how the doctor told them they have the bones of a 70-year-old, and could end up stooped over from vertebral fractures, or breaking a hip just by stepping off the kerb.
After this devastating news, these women are often afraid to take part in vigorous activity, when the scientific evidence shows that is exactly what they should keep on doing (or start doing), in order to maintain strong bones and avoid fracture!
Let’s explore the myths that make up the Great Osteoporosis Scam.
Myth #1: Osteoporosis = low bone mineral density.
Fact: In the past, osteoporosis was defined as “an enlargement of the spaces of bone (Haversian canals) whereby a porous appearance is produced”. Only a person who had already suffered a low-trauma fracture was diagnosed with osteoporosis – that is, it was a disease with definite symptoms.
The invention and proliferation of DXA (dual x-ray absorptiometry) machines, which allow doctors to measure the density of mineral content in their patients’ bones, completely changed the definition of osteoporosis.
Now osteoporosis is a condition (usually without any symptoms whatsoever) defined with reference to the bone mineral content of an ‘average’ healthy 25-year-old white woman. A person whose BMD is more than 2.5 ‘standard deviations’ (a statistical measure of variance) below this ‘average’ person is said to have osteoporosis, while being 1-2.5 standard deviations below that average earns you a diagnosis of osteopaenia.
It is important to realise that DXA scans do not detect the enlarged spaces in bone that characterise osteoporosis; they merely measure your BMD and compare it to a ‘norm’ based on a 25-year-old white woman. This leads on to Myth # 2.
Myth #2: The reference standards for osteoporosis and osteopaenia are based on good science.
Fact: The diagnostic standards quoted above were arbitrarily set by a World Health Organisation (WHO) working party with significant conflicts of interest.
The WHO working party convened in Rome in 1992. A fascinating program made by US National Public Radio describes the completely unscientific process that they used to set the diagnostic criteria for osteoporosis:
“The question before the experts in Rome then was this: Since after the age of 30 all bones lose density, how much bone loss was normal? And, how much put women at risk and therefore should be considered a disease?
Anna Tosteson is a professor of medicine at the Dartmouth Institute for Health Policy and Clinical Practice and Dartmouth Medical School who attended the meeting. She says that over a two- or three-day period the experts in the room went back and forth and back and forth, looking at research and trying to decide precisely where on a graph of diminishing bone density to draw a line.
“Ultimately it was just a matter of, ‘Well … it has to be drawn somewhere,’ ” Tosteson says. “And as I recall, it was very hot in the meeting room, and people were in shirt sleeves and, you know, it was time to kind of move on, if you will. And, I can’t quite frankly remember who it was who stood up and drew the picture and said, ‘Well, let’s just do this.’ “
So there in the hotel room someone literally stood up, drew a line through a graph depicting diminishing bone density and decreed: Every woman on one side of this line has a disease.
Then a new question arose: How do you categorize the women who are just on the other side of that line?
To address this issue, Tosteson says, the experts — more or less off the cuff — decided to use the term osteopenia. Tosteson says they created the category mostly because they thought it might be useful for public health researchers who like clear categories for their studies. They never imagined, she says, that people would come to think of osteopenia as a disease in itself to be treated. The chairman of the meeting, John Kanis, of the WHO Collaborating Centre for Metabolic Bone Diseases, says the same thing.”
As the NPR piece makes clear, the push to redefine osteoporosis by reference to DXA measurements of bone mineral density emerged from an unholy alliance between the pharmaceutical industry and the makers of DXA scanning equipment.
Specifically, Merck, the manufacturers of Fosamax, an osteoporosis drug that was selling poorly due to the low numbers of people diagnosed with osteoporosis, established a nonprofit, the Bone Measurement Institute, which successfully lobbied for insurance coverage of bone mineral density testing Once DXA scanners became profitable, diagnoses of osteoporosis and osteopaenia skyrocketed, and Fosamax went from a fizzer to a blockbuster drug.
Additionally, the WHO study group was partially funded by three major drug companies which produce drugs to treat osteoporosis. Obviously, it was in their interests to define osteopaenia and osteoporosis in such a way that eventually, the majority of women (and a significant proportion of men) would fit the diagnosis.
The reference standard of the ‘average’ healthy 25-year-old does not take into account either build – people with a smaller build quite naturally have lower bone mineral density, and this does not increase their risk of fracture; or race – there are dramatic differences in average bone mass between ethnic groups. For example, a study of Hawaiian, Filipino, Japanese and Caucasian women found there was significant variance between different ethnicities. (Notably, there was also 50–100 per cent variance in bone mass in individuals within all four ethnic groups.)
Myth #3: if you have low BMD you are automatically at increased risk of fracture.
Fact: BMD is a poor predictor of fracture risk, with both low sensitivity and low specificity.
In a blistering critique of the widespread use of DXA scanning, S. Pors Nielsen, of the Department of Clinical Physiology and Nuclear Medicine, Hillerød Hospital, Denmark, crisply summarised the key limitations of this technology, and the T scores based on it which are used to guide recommendations for prescription of osteoporosis drugs:
“BMD is not an ideal measure of true bone density; it is not an ideal measure of bone strength; it does not predict fractures well; and it has inherent problems of accuracy. The limitations of BMD, based on the physical deficiencies of DXA, are further obscured by the introduction of T-scores.”
The Fallacy of BMD: A Critical Review of the Diagnostic Use of Dual X-ray Absorptiometry
Many low-impact fractures occur in people with normal or high BMD, while many people with low BMD will never suffer a fracture:
“BMD measurements are poor predictors of whether individual women will suffer future fractures. In fact, most women will be misclassified if they are sorted according to BMD scores. Regardless of the threshold chosen, most women who will suffer a hip fracture (the most consequential fracture) will be classified as normal when compared with the mean (average) BMD of women the same age.
If women more than one standard deviation (SD) below the mean are classified as being at increased risk for fractures, then 70% of the women who will eventually suffer fractures will not come from the group identified as being at risk. At the same time, only half of the 30% of women labeled as being at increased risk will have a fracture. The other half will receive unnecessary treatment. Selecting women below two SD will not solve the problem: 87% of fractures will be missed, and 5% of those selected will not suffer fractures.”Does Evidence Support the Selective Use of Bone Mineral Density Testing in Well Women?
Reduced bone mineral density is just one risk factor for low-trauma bone fracture. The undeniable fact is that most people who suffer such fractures have multiple risk factors for poor bone health and/or heightened risk of falling, including:
Being elderly (over 85);
Being inactive (which reduces muscle strength, balance and co-ordination, thus increasing the risk of falling);
Suffering from dementia or Parkinson’s disease (which also affect balance and co-ordination);
Suffering from cancer, chronic liver disease, or diseases that cause malabsorption;
Smoking cigarettes;
Drinking alcohol regularly;
Taking medications that affect balance, co-ordination or alertness such as sleeping pills and anticonvulsants, or that impair bone health such as antidepressants, proton pump inhibitors and glucocorticoids; and/or
Having failing vision (which increases the risk of tripping).
The risk assessment tools that NICE recommends (FRAX and QFracture) take these factors into account.
Myth # 4: A high intake of calcium, especially from dairy products, prevents osteoporosis.
Fact: There is no reliable evidence for the dairy industry’s claim that consuming dairy products is good for your bones.
In a 2020 systematic review and meta-analysis, cohort studies – considered the strongest form of epidemiological study design – did not find any protective effect of milk and dairy intake on risk of osteoporosis and hip fracture, while “every additional 200-gram milk intake per day was associated with a 9% greater risk of hip fracture”.
Previous meta-analyses have reported similar findings: no evidence of protective effects of milk consumption, and no link between low milk consumption and hip fracture risk.
As for calcium, a meta-analysis of multiple large cohort studies and randomised clinical trials found that calcium intake does not affect fracture risk in either women or men; calcium supplementation does not reduce fracture risk; and calcium supplementation without vitamin D may actually increase hip fracture risk.
Ok, so that’s the industry-sponsored myths dispatched with! Now for the most important part:
How to keep your bones strong and healthy – for life
Exercise regularly
When you do any kind of physical activity that puts some stress on your bones, cells within the bone sense this stress and respond by making the bone stronger and denser. Such weight-bearing exercise (including walking, dancing, jogging, weightlifting, stair-climbing and racquet sports) causes the bones to retain density and resistance to fractures, throughout life. You need a variety of exercises or activities that put stress on different parts of the body, to keep all your bones healthy.
Exercise also increases muscle strength and coordination, helping to maintain balance and avoid falls.
Optimise your vitamin D level
Vitamin D has long been known to be a crucial factor in bone health, both promoting intestinal absorption of dietary calcium, and preventing parathyroid hormone-induced breakdown of bone.
A meta-analysis of 11 observational studies, involving over 39 000 participants, found that for each increase of 10 ng/mL (ie, 25 nmol/L) in serum vitamin D concentration, the relative risk of any fracture was reduced by 7 per cent, and the risk of hip fracture by 20 per cent.
But while low-dose vitamin D supplements are probably ineffective for fracture prevention, high-dose supplements may be outright harmful:
“High vitamin D doses, either at monthly (60,000-100,000 IU) or daily intervals (>4000 IU), appear to be harmful with regard to falls, fracture risk and BMD, especially for people without vitamin D deficiency and at low fracture risk.”
Vitamin D supplementation and fracture risk: Evidence for a U-shaped effect
The best way to secure an optimal vitamin D level is from judicious sunlight exposure, just the way nature intended. Getting sunlight on our skin produces a host of photoproducts besides vitamin D production, including:
Nitric oxide, which has beneficial effects on cardiovascular function;
Serotonin, a neurotransmitter involved in mood, cognition, regulation of eating behaviour, anxiety, aggression, pain, sexual activity, and sleep;
Endorphins, which induce mood enhancement and relaxation, reduce depression and provide pain relief; and
Melatonin, which regulates circadian rhythm and also has potent anti-oxidant properties.
The Vitamin D Society has useful tips on getting a safe amount of sunlight exposure without risking harmful sunburn.
The dminder app takes this to the next level, giving customised recommendations for safe sun exposure based on latitude, time of year, skin type, age, weight and other factors that influence vitamin D production.
Get adequate vitamin K
Vitamin K, which is found mainly in green, leafy vegetables, contributes significantly to calcium regulation and bone formation. The Nurses’ Health Study found that women who ate more green, leafy vegetables (even lettuce!) had a 70 per cent lower risk of hip fracture than those with the lowest intake of vitamin K-rich foods.
Low blood levels of vitamin K have consistently been found to correlate with increased risk of fracture in different populations.
On the other hand, s
upplementation trials have yielded mixed results, so at this stage, I recommend getting your vitamin K from food rather than pills.
So, there you have it. Maintaining healthy bones for life largely comes down to diet and lifestyle choices that are in your hands (and in your feet, if you count exercise).
To make matters worse, bisphosphonates increase the risk of so called “atypical” femur fracture, hence even if they work to prevent neck of femur fracture, the outcome regarding femoral fractures would be six or half a dozen. I’m beginning to think most of allopathic medicine is just outright fraud.
What about the effect of fluoride on the bones? I had been lead to understand that a lot of what is diagnosed as osteoporosis (whether by the DEXA scans or other means) is in fact skeletal fluorosis. I wonder what your understanding of this is, Robyn? Thank you... Mary