title: Evidence from prospective cohort studies did not support the introduction of dietary fat guidelines in 1977 and 1983: a systematic review.
abstract: OBJECTIVE
  National dietary guidelines were introduced in 1977 and 1983, by the USA and UK governments to reduce coronary heart disease (CHD) mortality by reducing dietary fat intake. Our 2015 systematic review examined randomised controlled trial (RCT) evidence available to the dietary committees at the time; we found no support for the recommendations to restrict dietary fat. What epidemiological evidence was available to the dietary guideline committees in 1983?
  
  
  METHODS
  A systematic review of prospective cohort studies, published prior to 1983, which examined the relationship between dietary fat, serum cholesterol and the development of CHD.
  
  
  RESULTS
  Across 6 studies, involving 31 445 participants, there were 1521 deaths from all-causes and 360 deaths from CHD during the mean follow-up of 7.5±6.2 years. The death rates were 4.8% and 1.1% from all-causes and CHD respectively. One study included men with previous heart disease. The death rate from CHD for those with, and without previous myocardial infarction was 20.9% and 1.0% respectively. None of the six studies found a significant relationship between CHD deaths and total dietary fat intake. One of the six studies found a correlation between CHD deaths and saturated dietary fat intake across countries; none found a relationship between CHD deaths and saturated dietary fat in the same population.
  
  
  CONCLUSIONS
  1983 dietary recommendations for 220 million US and 56 million UK citizens lacked supporting evidence from RCT or prospective cohort studies. The extant research had been undertaken exclusively on males, so lacked generalisability for population-wide guidelines.
authors.affiliation: Institute of Clinical Exercise and Health Science, University of the West of Scotland, Hamilton, Lanarkshire, UK.
authors.forename: Zoë
authors.initials: Z
authors.lastname: Harcombe
authors.affiliation: Institute of Clinical Exercise and Health Science, University of the West of Scotland, Hamilton, Lanarkshire, UK.
authors.forename: Julien S
authors.initials: JS
authors.lastname: Baker
authors.affiliation: University of South Wales, Pontypridd, UK.
authors.forename: Bruce
authors.initials: B
authors.lastname: Davies
mesh_terms: D003327:Coronary Disease / Q000453:epidemiology* / Q000517:prevention & control; D004032:Diet; D004041:Dietary Fats / Q000008:administration & dosage*; D006801:Humans; D009203:Myocardial Infarction / Q000453:epidemiology; D016032:Randomized Controlled Trials as Topic; D064167:Recommended Dietary Allowances; D006113:United Kingdom; D014481:United States
chemical_list: D004041:Dietary Fats
keywords: Cholesterol; Cohort study; Dietary; Heart disease; Public health