Blog | Wednesday, November 14, 2012

A skeptical look at weight loss, exercise and preventing strokes

A theme woven throughout the Whistleblower blog is skepticism. I endorse and rely upon this in my medical practice and in my life. I admit that there were times that I argued a point that was not truly my own at the dinner table simply to stimulate the minds of my progeny. As the kids are not readers of this blog, I trust that actual readers will be protective of this knowledge that if released could sow a storm of familial strife.

I am reluctant to incorporate new medical breakthroughs into my practice until enough time has passed to convince me that these medicines or treatments are truly safe and effective. Often, the test of time exposes the vulnerabilities and hazards of new remedies for old maladies. This is to be expected. Once a new medicine is released into the marketplace, its true risks may not be known until thousands of patients have taken it.

On other occasions, new science retires old treatments. When I was a younger physician during the Pleistocene Epoch when I used to take my pet triceratops out for a walk, we gave nearly all women hormone replacement as a guard against the heartbreak of bone breaking osteoporosis. Now, a physician who would make such a recommendation would be labeled as a medical fossil from the Jurassic Period, and would be labeled as a medical dinosaur and would be encouraged to limit his practice to administering influenza vaccines.

In medicine, and beyond, don't believe stuff that sounds as if it should be true. This is one of the dangers of the surrogate marker, a medical research sleight of hand that tries to substitute an outcome of limiting meaning for another that the researcher wants to be true.

Of course, it's a fact that there is excess obesity in the United States and in many other countries. Weight loss has become a national crusade that has even entered corporate America who increasingly incorporate weight loss and fitness into their wellness programs.

It is also a fact that obesity is associated with many medical conditions such as heart disease, arthritis, strokes and cancer. Many folks, however, confuse a medical association from actual causality. For example, exercising in a gym may be associated with better health, but these workouts may not be the cause of the desirable outcome. Gym freaks may be healthier because of their diet or lifestyle. They may have access to higher quality medical care. So the headline, "Gym Users Have Fewer Heart Attacks," is rather misleading.

It is taken as fact that weight loss, which is associated with many diseases, will reduce the risk of these diseases, but is this really true? I know that even posing this question constitutes medical heresy, a charge that has been leveled against me from time to time. The New York Times reported that a study of weight loss was stopped two years ahead of schedule because an aggressive program of diet and exercise did not reduce heart attacks, strokes or cardiac mortality even though the study group lost 5% of their weight, a significant amount.

Those who are biased over the true medical value of weight loss will criticize the study. Medical skeptics, however, will gloat about it on their blogs.

This post by Michael Kirsch, MD, FACP, appeared at MD Whistleblower. Dr. Kirsch is a full time practicing physician and writer who addresses the joys and challenges of medical practice, including controversies in the doctor-patient relationship, medical ethics and measuring medical quality. When he's not writing, he's performing colonoscopies.