What does “normal” really mean when it comes to lab tests?

Naturopathic and functional medicine practitioners often interpret conventional labs more carefully than just a binary determination of “normal/abnoral”. There is good reason for this. A more careful look at lab values can an ammount to a life preserver for medical refugees who are castaways from strict interpretations.

Shoe size is a good analogy regarding lab interpretation. Most labs define “normal” as the average result of a pool of asymptomatic patients plus or minus 2 standard deviations. This covers about 90% of the “normal” population. If you were to use this standard to determine what the average shoe size was, it would probably be somewhere between 6 and 12. Given biological individuality, it becomes rather absurd to suggest that you could give any human being a shoe between size 6 and 12 and expect it to fit. Continue reading “What does “normal” really mean when it comes to lab tests?”