After been hammered with the low fat mantra during 30 years. Every child, adult men and women underwent a massive  experiment. People made a substantial reduction of saturated fat content of their diets in the hope of reducing the prevalence of cardiovascular disease (CVD). Currently, we know that this experiment was based on weak evidences as well as institutional and personal bias.
The saturated fat content of the diet is NOT associated with cardiovascular disease. A systematic review of 146 prospective cohort studies describing 361 subcohorts and 43 randomized clinical trials (RCT)  involving 51 subgroups did not find evidence supporting a causal link between dietary saturated fatty acids or total fat and Coronary Heart Disease (CHD)[1]. Likewise a meta-analysis of 21 studies prospective epidemiologic studies showed that there is no significant evidence for concluding that dietary saturated fat is associated with an increased risk of CHD or CVD [2].
The reduction of the percentage of fat in the diet does NOT reduce the incidence of cardiovascular disease. One meta-analysis, pooling 8 clinical trials described that replacement of some dietary saturated fat  with PUFA reduces CHD and  that the benefits associated with PUFA consumption increased with longer duration of the trials[3]. The Cochrane Collaboration is an international network of individuals and institutions that review and analyze the best clinical trials available on various subjects, and synthesize them into regularly updated systematic reviews. The information found in Cochrane is considered by many to be the Gold Standard. When the prevention of CVD through reduction or modification of dietary fat was addressed with a meta-analysis of 48 RCT, their review suggested that modification (not reduction), of at least two years duration and in studies of men (not of women), decreased the risk of cardiovascular events. More importantly, there were no clear effects of dietary fat changes on total mortality[4]. Where we stand now: Industrially produced trans fatty acids (TFAs) are consistently associated with a higher risk of CVD (on a gram-for-gram basis) and meta-analyses of cohort studies state that  saturated fat  intakes are not associated with CHD, stroke, or CVD.

[1] Mente A, de Koning L, Shannon HS, Anand SS. A systematic review of the evidence supporting a causal link between dietary factors and coronary heart disease. Archives of internal medicine. 2009 (PDF)
[2] Siri-Tarino PW, Sun Q, Hu FB, Krauss RM. Meta-analysis of prospective cohort studies evaluating the association of saturated fat with cardiovascular disease. The American journal of clinical nutrition  2010 (PDF)
[3] Mozaffarian D, Micha R, Wallace S. Effects on coronary heart disease of increasing polyunsaturated fat in place of saturated fat: a systematic review and meta-analysis of randomized controlled trials. PLoS medicine 2010 (PDF)
[4] Hooper L, Summerbell CD, Thompson R, Sills D, Roberts FG, Moore H, Davey Smith G. Reduced or modified dietary fat for preventing cardiovascular disease. Cochrane database of systematic reviews 2011 (PDF)

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