Dem Bones Dem Bones

I have received a request to discuss the treatment for osteoporosis, so here are my two or three cents.  Feel free to make additional requests.  You can leave a comment on this blog or send an email to me at mpf9973@bjc.org.

During our younger years most of us take our bones for granted.  They carry us from place to place remarkably well.  They are quite resilient and only give way under a significant amount of stress.  As we get older that changes.  I have had a patient break their pelvis by nearly bending over to pick up a load of laundry.  Slips and falls can easily lead to broken hips, collar bones or arms.  The back bones can spontaneously implode on themselves like a stepped on soda can.  Not only are all these situations extremely painful, they are dangerous as well.  If an 80 year old falls and breaks a hip, there is a 50% chance that they will no longer be alive within six months.  It takes longer to heal at that age.  The immobility will predispose one to blood clots.  Pneumonia is more common.  The physical stress of the fracture may trigger a heart attack.  Muscle wasting occurs, making future falls even more likely.  This is the reason why physicians are so concerned about your bones.

Osteoblast: Bone Builder

Osteoclast: Bone Eater

The time to act is now, not after a fracture has happened.  By that time the bones are already brittle and weak.  To understand the different therapies used to improve bone strength, let me first explain bone metabolism.  One of the reasons why bone is so strong is that it is constantly being remodeled.  You can think of bones as scaffolding composed of calcium deposits.  There are two types of workers on the scaffolding, osteoblasts and osteoclasts. The osteoblast is the builder cell.  He is your brick mason, so to speak.  The osteoclast are the low paid college kids who come in and tear out the old bone that is showing signs of decay.  Think of calcium as the bricks used to build up the scaffolding.  The reason why people develop thin bones is because of an aberration in one of these three areas.  First, the youthful demolition workers may be over active.  Second, the deliberate mason builders may work too slow to match the demolition done by their younger counterparts.  Third, there may be a deficiency of material to work with (not enough calcium).  An example of the first are people given anti-inflammatory steroids such as prednisone.  This turns on the osteoclasts and bone destruction is accelerated.  Women in menopause who lack the estrogen of youth have a decrease in the activity of their osteoblasts (mason workers).  Patients with Celiac disease don't absorb calcium as well and lack the material used to make the bones.  The same is true for patients taking long term anti-acid suppressant medications or patients with vitamin D deficiency.  An overactive parathyroid gland will result in pulling calcium out of the bones and into the blood stream.  Understanding the cause of why someone's bones are thin is important so as to recommend how to counteract those effects.

The most important way to improve bone health is to be on them and be active.  There will never be a better solution than regular weight bearing exercise.  In as little as six weeks, well conditioned, young astronauts in space will begin to lose strength in their bones.  The same happens to anyone confined to bed for an illness.  Self imposed inactivity (nice way of saying "laziness") has similar effects.  When we are active and up on our feet our bones feel that pressure.  The mechanical reaction stimulates our osteoblasts to action and they get to work building more bone.  This won't do you any good if there is not adequate calcium to work with.  Calcium is mostly found in dairy products.  It is recommended that we obtain 1000-1200 mg of calcium a day.  Each serving of dairy contains approximately 300 mg of calcium.  The absorption of calcium is enhanced by the effects of vitamin D.  Vitamin D is activated by sun light.  As little as 10 minutes of sun exposure three days a week will suffice (see "Good Rays or Bad").  If you are not getting enough calcium through your diet, it is good to supplement that with a combination calcium-vit D tablet.  I recommend using 600 mg of calcium combined with 400 units of vitamin D, 1 or 2 tablets a day depending on your diet.  If you take a medication to block the acid in your stomach, using calcium citrate, which is absorbed better in an acid free environment than is calcium carbonate, which requires acid for absorption.

Regardless of what conditions affect your bones, adequate exercise, the appropriate diet and just enough sun exposure will help.  In a future post, I'll discuss how bone strength is measured and medications used to treat brittle bones.