The metabolic syndrome is a very common condition, characterised by insulin resistance, dyslipidaemia, abdominal obesity and hypertension, that is associated with a high risk of type 2 diabetes mellitus (T2DM) and CVD. Obesity is a key aetiological factor in the development of the metabolic syndrome. In light of the increasing prevalence of obesity, there is a high requirement to reduce the impact of the adverse health effects associated with the metabolic syndrome. The aetiological role of nutrient-derived metabolic stressors, in particular fatty acids, in the development of obesity and the metabolic syndrome is explored. Also, the evidence that pro-inflammatory stressors may predispose to obesity-induced insulin resistance is reviewed. The present paper explores the concept that reducing the impact of metabolic and inflammatory stressors may reduce the adverse health effects of obesity and slow the progression towards the metabolic syndrome and T2DM. Evidence from human dietary intervention studies that have investigated the potential therapeutic effects of dietary fatty acid modification is explored. The present review highlights the requirement to take account of genetic background, within the context of nutrient regulation of gene expression and individual responsiveness to dietary therapy. This approach will further the understanding of the interaction between fatty acids in the pathogenesis and progression of the metabolic syndrome.