The Truth about Bisphosphonates (and Aromatase Inhibitors)

The Truth about Bisphosphonates (and Aromatase Inhibitors)

Bisphosphonates are widely touted as bone strengthening drugs, used in osteoporosis and oncology, but research shows they can actually worsen the brittle bone effects; as do Aromatase iInhibitors causing twice the problem if you use them together.

What are Bisphosphonates?

Bisphosphonates are described as a group of drugs that ‘slow down or prevent bone loss, strengthening bones’. Like most drugs, they are made from petrochemicals. And this is big business – trillions of dollars in size.

They are used in osteoporosis, Paget’s disease and in oncology, particularly with Aromatase inhibitors for breast cancer and to lower high calcium levels.

Best known are Zoledronic Acid, Alendronate, Etidronate, Risedronate, Ibandronate (1).

How do Bisphosphonates work?

Bone is made by osteoblasts, and this process necessitates calcium, magnesium, vitamin D and a little phosphorus.

The American Association for Bone Health states that “Mounting evidence shows that too little calcium in the diet (less than 500–600 mg a day) is harmful, but too much calcium (adding calcium supplements when the intake is already 1,000 mg) also may be harmful” (2).

The view is that 600 - 1000 mg of total calcium per day is adequate along with 800 IUs (20 mcg) of Vitamin D. If osteoporosis is the issue, the ABH recommends 1200 mg calcium, but up to 2,000 IUs (50 mcg) of vitamin D per day. Bear in mind that this is ‘total calcium consumed’ and a good helping of greens at dinner will provide about 800 mg of calcium. One serving of dairy is 300-500 mg of calcium. Bear in mind secondly, that there are a number of studies linking high calcium with heart issues.

At this point you might be expecting me to say that Bisphosphonates somehow stimulate osteoblasts. Sadly nothing could be further from the Truth.

Bisphosphonates and bone destruction

Bisphosphonates kill osteoclasts, which are cells that break down old bone; this process is critical to healthy bone renewal – the osteoclast enzymes break down bone so that the components can be re-used to make new bone. It’s called 'resorption'. This function is critical to the maintenance, repair and remodelling of bones, so that osteoblasts can make new bone. In that way your bones remain healthy and strong.

But when the Bisphosphonates kill off the osteoclasts, the new bone is still created - the bone adds cells but they are deficient and the new bone becomes brittle. Result? More fractures. The Medical Website state that Bisphosphonates are “associated with atypical femur fractures, osteonecrosis of the jaw and esophageal cancer. Experts recommend the need for bisphosphonate treatment should be reviewed every three to five years”. An atypical fracture is one where you were not in an accident (1).

FDA warnings

And here’s the rub. These drugs are supposed to be bone strengthening drugs, yet they cause fractures in the femur or hip. And this apparent flaw is well researched. In 2010, the FDA even ordered on pack warnings. Just so you know, it can take approximately 5 years before brittle bone occurs.

Aromatase Inhibitors are associated with fractures too

According to Dr. Edith A Perez and others in their Oncology journal review on aromatase inhibitors (3), “AIs are associated with significantly more osteoporotic fractures and greater bone mineral loss”.

Bone mineral loss? Isn’t that the same as you get with bisphosphonates?

Perez went on to say, “As anti-resorptive agents, oral and intravenous bisphosphonates such as alendronate (Fosamax), risedronate (Actonel), ibandronate (Boniva), pamidronate (Aredia), and zoledronic acid (Zometa) have efficacy in preventing postmenopausal osteoporosis, cancer treatment-related bone loss, or skeletal complications of metastatic disease”.

So anti-resorptive? Adding Bisphosphonates to stop bone breakdown when they block mineral resorption, isn’t this just doubling the problem?

Now let's see. I know, what we will use to prevent AIs causing brittle bones are Bisphosphonates which, err, cause brittle bones.

To confirm, this time from the Susan G. Komen breast cancer website – “Aromatase inhibitors cause a loss of bone density, which leads to higher rates of osteoporosis and bone fractures”. Ah, now I get it. Oncologists think that Bisphosphonates stop bone fractures in cases of Osteoporosis. They obviously haven’t read the on pack FDA warning.  

Logic suggests that you wouldn’t even think to give a woman a bisphosphonate if she was at risk of bone loss from Letrozole or Anastrozole. You'd merely be doubling the dilemma.

As the current 'science in practice' seems questionable, let’s turn to research for the answer.

Before I give you the evidence-based conclusions I just want to tell you that in bone health there is something called BMD – Bone Mineral Density. According to the American National Institutes of Health, Osteoporosis and related Bone Diseases Resource Centre, BMD is a measure of bone health. A BMD-T score compares your bone health to that of a young person. The norm is zero. Lower scores mean more risk of fractures.

ADRs can occur too – it’s where you need an Artificial Disc Replacement in your back because of brittle bones.

Meta Review – Ais and Bisphosphonates

Let’s look at a meta-review of different Bisphosphonates, following having AI drugs prescribed for women with breast cancer. The researchers selected 6 of the many studies from 1995 to 2013 as being the most reliable. Of the 6 studies some were for ‘normal’ BMD scores at the outset, while a second group were people with osteopenia at the outset of the trial. Let me quote:

  • A total of six eligible studies reported the BMD T score of LS at 12 months 

Excuse me, but why are we looking at only 12 months? As you read above, three – five years is the time frame for fractures?!

  • A group taking Zoledronic acid immediately vs a group delaying the start - Both had a significant decrease in BMD
  • 3 trials of risedronate and ibandronate also had a significant decrease in BMD
  • Conclusion. Third generation bisphosphonates have an effect on BMD of patients who are on treatment of AIs in breast cancer.

Yes, a negative one and that’s in the first 12 months!

  • Furthermore, the patients treated with immediate Zoledronic acid had a significantly high risk of musculoskeletal ADR’s than patients with delayed Zoledronic Acid.

Game, set and match!

Ways to prevent osteoporosis naturally

Let’s be clear. These drugs do not promote stronger bones. They all promote brittle bones; and a chunk of chalk and a paltry 400 IUs of vitamin D in Adcal from the oncologist is definitely NOT going to prevent this. In fact, it’s not even science, it’s little more than witchcraft, with no hard evidence in their support.

The DIY solution? Well, apart from the calcium, magnesium, phosphorus and vitamin D protocol above, you might add glutathione-promoting compounds – alpha lipoic acid, N-acetyl cysteine, selenium and green vegetable juices. You also could do weight-bearing exercise.

Well, that’s what the ABH people say. At last, people talking science sense!!



  2. American Bone Health
  3. ONCOLOGY Vol 20 No 9, Volume 20, Issue 9; Edith A Perez, MD., Katherine Weilbaecher, MD.
  5. Journal of Oncology, Hindawi, 26 March 2014, Poolerveetil Padikkai Anagha


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