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Saturday 15 December 2018

We read this: "Your bones".

This is review of the book  “Your Bones”, a medical book aimed at the general public by Lara Pizzorno and with Jonathan V. Wright. The review was co-authored with Gabriela Cardillo; she provided the body, medical expertise, and main content and I edited and added the criticisms and asides at the end.

“Your Bones” by Lara Pizzorno and with Jonathan V. Wright is a medical book aimed at the general public. It has plenty of citations for its claims, but the language itself is as non-clinical as possible. Most non-trivial medical terms are explained clearly. "Your Bones" is, or at least the first couple of chapters of it are, a rebuke of a class of conventional drugs called bisphosphonates.

It starts with a description of the core mechanics behind osteoporosis and why women are at a much higher risk than men. In general, the trigger is hormonal changes during menopause, and in specific, it’s the resulting excessive action of osteoclasts in pruning sub-optimal bone, and diminished action of osteoblasts in creating new bone to replace it.

Bisphosphonates, the commercially prevailing class of drugs (called in the book ‘patent medicines’) only work to inhibit osteoclasts and ‘preserve old bone’ rather than promote the production of newer replacement bone. On top of the inherit incompleteness of this treatment, it also interferes with the growth of new bone by now allowing new places for it. Because of the heavy wear that the mandible / jawbone receives and the large amount of blood flow to the jaw, bisphosphonates accumulate (much like the bio-accumulation of mercury in predators) in the jaw and cause greater long-term bone damage there. So much so that the mandible completely dies in about 0.1% of long term users of bisphosphonate patent medicine.

Along with other side effects like esophageal cancer, one notable consequence of poisoning one’s osteoclasts is that the calcium from the dead or damaged bone is not reabsorbed into the body. This causes symptomatic hypocalcemia, which, as calcium is used in nerve impulses, can cause a host of dangerous symptoms related to nerves firing properly. These include seizures, dementia, and bronchospasm, and heart failure.

The main effect, as in the intended effect of bisphosphonate patent medicines is to prevent osteoporosis, but instead they somehow manage to increase the risk of fragility fractures, as well as increase the recovery time. This risk increases with the time that bisphosphonates have been taken. The time until use of bisphosphonates is responsible for such a fracture is a startlingly short five years. The reason that these drugs ever made it to market is that they do manage to have a statistically significant* benefit in the short term.

Rather than rely on patent medicine to maintain healthy bones, “Your Bones” refers to the COMB study, which recommends weighted exercise to put a regular, managable amount of stress** on your bones and muscles, as well as post-menopausal supplements of some key vitamins and minerals.

One surprising fact was that the effect of the micronutrient genistein seems to have a promotional effect on bone growth at the 30mg/day dosage found in traditional Japanese diets, but a mixed or inhibitory effect at the 80-200 mg/day level found in various supplements. That, along with other micronutrients found in a supplement called geniVida is credited in the book with a 2.3% gain in bone-mass density over the course of the six-month study on post-menopausal women, compared with a 1.1% loss in the placebo group.

One quote that resonated with me is “a “silver bullet” … can fix our disintegrating bones to a much more intelligent comprehensive paradigm that prescribes a healthy dose of all the nutrients our bones require plus regular weight-bearing exercise.”. In short, the authors are heralding a shift to holistic medicine.

I have two criticisms. First is the length of the introductory problem statement. After 60 pages, I was fully convinced that bisphosphonate-based drugs were terrible, a modern thadlidomite even. After those 60 pages, there was a 20-30 page going over yet more evidence of the same, that, I admit, I skimmed. It’s hard to imagine a reader that would get much from this extended introduction that they wouldn’t have already gotten halfway through. The harm in making an introduction this long is that delays the call to action, the proposed solution, and probably has led to some reader attrition before the part about natural supplements is even reached.

My second criticism has to do with the word ‘natural’. In the first couple of pages in the foreward, the authors espouse the evils of patented drugs for being unnatural. There’s even a generalization that “since our bodies were [made] from entirely natural materials, patent medicines are fundamentally incompatible with the design of the human body.”. Being natural doesn’t automatically make something better; arsenic is natural, cancer is natural, rice that produces vitamin A to prevent blindness is not. Bisphosphonates aren’t bad because they’re unnatural, they’re bad because they’re poisonous; introducting the naturalistic argument confuses the case against them.

*Aside about the drug discovery process: The statistical burden of proof for a drug to be cleared by North American drug authorities like the FDA is just that there is statistically significant evidence of an effect, which just means that you can show that the effect is measure. This isn’t the same as clinically significant – a drug can have a measurable effect, and that effect can still be too small to make a meaningful difference)

**Aside about exercise stress and osteoporosis: There have been some fascinating studies on astronauts and microgravity. Being in a weightless environment for a prolonged time appears to cause osteoporosis at a much faster rate than aging on earth. In such conditions and without weighted (or equivalently, resistance) exercise, bone is reabsorbed for its calcium aggressively. In this case, the body ends up with too much free calcium instead of too little. Among the suggested treatments were vibrating the entire body to mimic day-to-day terrestrial stresses.

These vibrating plates are also used to exercise horses.

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