Mediterranean Diet - Friend or Foe?
With recent headlines suggesting "flaws" in one of the most popular and seemingly healthful diet patterns to date, the Mediterranean Diet, are we left to call it a day and banish avocado, fish, and vegetables from our health radar?
Prompting this recent upheaval now making some doubt what they once believed to be the holy grail of nutrition is the retraction of a 2013 study published in the New England Journal of Medicine. The study emphasized the role of the Mediterranean diet in reducing the incidence of heart attack and stroke.
Before jumping to conclusions, let's read beyond the headlines, understand the basis for the retraction, and determine whether the issue at hand is really the Mediterranean Diet.
Here's what we know: The Mediterranean Diet is known today as a heart-healthy eating pattern dating back to the eating styles of Ancient Romans and Greeks. It emphasizes such foods as fish and seafood, olive oil, plant-based foods like fruits and vegetables, and perhaps the occasional glass of red wine. It would be immoral to say that such an eating pattern is restrictive. For this reason, as a dietitian, I have always welcomed this approach. Its balance and emphasis on lifestyle rather than single foods, is perhaps also why the Mediterranean Diet has withstood the test of time over other single-minded diets or fads. It is not a diet, rather a way of life as the Greek work "diaita" denotes.
Here's what we also know: A retraction of a paper implies that the validity of the research study is being questioned. The basis for this questioning can depend on multiple factors, ranging from human error to academic or ethical misconduct.
The detector of the flaw in the study at hand, Dr. Carlisle of Torbay Hospital in England, found that one study site did not follow proper randomization procedures, thus failing to adhere to true randomized controlled trial standards. In other words, other members of the study subjects' households may have been included, and so the trial would not exactly be random as the name suggests. Results from reanalysis by the New England Journal of Medicine were not far off from the original. A revision paper is to be released with both results. The other major change in the revision will be verbiage - rather than stating that the heart-health benefits observed in the study were a direct result of the Mediterranean Diet, the revised version will note that subjects who followed the diet experienced fewer heart-related events.
So what should we make of this?
For starters, it is important to remember that this particular study was one of many. There still exists a substantial body of evidence in support of the health benefits of this dietary pattern. This evidence is backed by other strong, randomized controlled studies which investigate the diet's role in the reduction of heart-related events, its effect on cardiovascular markers like blood pressure or vascular inflammation, and even its role in the prevention of Type 2 Diabetes. There is also a ton of ongoing research supporting the health profile and benefits of foods emphasized by the Mediterranean eating pattern.
Moral of the story - let us be wary of human error, but also of reductionist headlines.
More importantly, let us carry on with a healthful, balanced, and of course delicious approach to eating and living.