The low fat, low saturated fat mantra has been chanted so loudly and so often that many people believe it must have solid scientific support (it does not). There will be a brief description of the historical development of the saturated fat-cholesterol hypothesis that begat the low fat doctrine in popular diet and nutrition circles and presentation of the scientific evidence that shows the inaccuracies and false assumptions of those hypotheses. Numerous studies in recent years have shown that saturated fatty acids, palmitic acid in particular, can increase levels of several inflammatory markers in vitro, although these studies have not shown exacerbation of inflammatory diseases in vivo. There will be some discussion of the role of saturated vs omega-3 and omega-6 polyunsaturated fatty acids in inflammatory syndromes, metabolic disorders and cardiovascular disease. The effect of high sugar diets on all of these metabolic consequences will also be discussed in the context of human health.