Lactate-The bad boy of metabolism, or simply misunderstood?

Lactate has been studied in great depth, particularly in the field of exercise physiology, yet its role in metabolism remains in many ways an enigma to the physiologists, causes consternation to clinicians and confusion to those in training. The aim of this article is to marry what we know about lactate physiology with its clinical relevance and implications in everyday medical practise. The initial approach to this requires an understanding of basic lactate metabolism from which one can then examine the relevance of high blood lactate (hyperlactataemia); whether this is harmful or beneficial and how it relates to critical illness.