In a watershed 1980 paper in the New England Journal of Medicine, Fries described the reserve of function in the body’s organs that, in youth, is well above what is needed for average everyday living. It’s like a savings account of extra biological capability that we can draw on when we need to—say, when we confront trauma, injury, or illness. At a

1. Assimilation and Elimination.

3. Defense.

our skeleton is remodeled every five to seven years.

Animal studies, like those by Dr. Michael Skinner of Washington State University, have shown that exposure to environmental toxins can result in epigenetic changes transmissible to the next generation and can create increased incidence of chronic disease.

But functional medicine isn’t concerned solely with health problems; it isn’t looking at the connection between your outside world and your inside physiology just to rid your body of its health problem. Rather, its systems approach is a way of finding the proper match between your genetic uniqueness and your environment, lifestyle, and behavior so

Blood pressure, percentage of body fat, the level of glucose or triglycerides or cholesterol in our blood, the way that cholesterol is packaged in LDL or HDL forms: these are just some of the more common biomarkers, all of them signals that indicate how our genes are being translated into physiological, physical, and mental functions—gauges of our

The standard test measures the amount of glucose in the blood after an overnight fast; an elevated level is a hallmark of the disease. But it is possible for a person in the early stages of diabetes to produce a normal result on the fasting blood sugar test. A more telling measure is to determine how well the body can metabolize glucose; this can b

Using the systems approach, functional medicine practitioners don’t stop looking if they can’t find a specific defective organ that can be “repaired” through acute care. They keep on going, exploring the entire physiological network to find the place or places where genetic expression has been altered by environmental factors. What they are looking