Cochrane saturated fat reviews

Introduction

A report was published on May 19th called “Reduction in saturated fat intake for cardiovascular disease” (Ref 1). It’s important because it’s a Cochrane review and Cochrane publications are seen as the gold standard in academic research. My personal view is that Cochrane tainted its reputation with the treatment of Dr Peter Gøtzsche, who was a co-founder of the Cochrane Collaboration and the former leader of the Nordic Cochrane Center in Copenhagen, Denmark. Peter was ousted from the Cochrane board in 2018 and he documented the events related to this in his book called “Death of a Whistleblower and Cochrane’s Moral Collapse.”

Notwithstanding this, Cochrane reviews are still as good as we get and so this one deserves attention. The Cochrane reviews have also focused on systematic review and meta-analysis of randomised controlled trials, and not population studies, which also adds to the value of the publications. This latest one has already been touted as “The [fat] War is Over: The New Report Finds Sat Fat Causes Heart Disease” (Ref 2). That article was written by one of the vegan leaders with no sense of irony given that the single food highest in saturated fat on the planet is coconut oil – pure vegan. Anyway, let’s take a look at this latest report, but first, the background... (This note will serve as a definitive account of all the Cochrane reviews on dietary fat – total and saturated).

Background

The first thing to note is that the 2020 report is not new, and it says nothing new. This is the fourth substantive Cochrane review of dietary fat – it’s the second one to emphasise saturated fat in the title. The lead author on all of these is Dr Lee Hooper, who works at the University of East Anglia. Hooper first published a Cochrane systematic review of dietary fat studies in 2000 (Ref 3). This paper was called “Reduced or modified dietary fat for prevention of cardiovascular disease.” It was updated in two publications in 2001. First in one called “Reduced or modified dietary fat for preventing cardiovascular disease“ (Ref 4). Second in one called “Dietary fat intake and prevention of cardiovascular disease: systematic review” (Ref 5).

The 2001 paper was the definitive Cochrane report until 2011 when a revised review was conducted and published. This one was called “Reduced or modified dietary fat for preventing cardiovascular disease. Cochrane database of systematic reviews” (Ref 6). This was also updated the following year, 2012, with the same title (Ref 7).

The 2011/2012 report was then updated in 2015 with a report called “Reduction in saturated fat intake for cardiovascular disease” (Ref 8). Please note that dietary fat was dropped and replaced with saturated fat in the title and focus of this review. This reflected the 2015 US Dietary Guidelines, which went quiet on total fat, but continued the war on saturated fat.

I was particularly amused by the 2015 report because I might have had a hand in it being done. The first major paper from my PhD was published in February 2015 and it ‘went viral’, as the saying goes (Ref 9). It became the 64th most impactful paper in any discipline in 2015 (Ref 10). It concluded that there was no evidence base for the introduction of the two dietary fat guidelines introduced in the US in 1977 and in the UK in 1983 (no more than 30% of calories in the form of fat and no more than 10% of calories in the form of saturated fat).

The powers-that-be might have thought that this needed to be countered. The 2015 Cochrane report opened by referencing my paper, in the first sentence under the heading “Why it is important to do this review.”

Finally, we have the 2020 report published on May 19th. Let’s look at each of the four clusters of reports: 2000/2001; 2011/2012; 2015 and 2020…