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Are some diets “mass murder”?

BMJ 2014; 349 doi: https://doi.org/10.1136/bmj.g7654 (Published 15 December 2014) Cite this as: BMJ 2014;349:g7654

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Unfortunately this feature article is not based on solid and holistic scientific data and conveys wrong signal to readers. Many claims are drawn from the named best-seller and unfortunately exaggerating diet books. Books are not subject to any kind of rigorous scientific fact-checking and consequently should not be considered as reliable proof of evidence.

What is healthy and what is not, is determined by quantity and quality of dietary studies in humans. It's clear that we need more randomized morbidity and mortality studies. But until they are done (if ever) we must rely on best available evidence and this often means prospective cohorts, case-control studies and randomized surrogate marker studies.

A recent exhaustive review of systematic reviews and meta-analyses comprised these study types. The review contained all major systematic reviews published between 1950-2013, in all 304 reviews, obviously more than 1000 individual studies. Obesity, type 2 diabetes, cardiovascular disease, cancers and 6 other diseases were under scrutiny. The authors concluded "… these results substantiate certain a priori nutritional recommendations... ". [1]. What is healthy food did not change after this robust review.

Following *officially recommended* diet is associated with substantially reduced risk of heart disease, cancer, type 2 diabetes and obesity in many other meta-analyses and pooled analyses of prospective cohorts as well. Details can be found in this slide deck: http://goo.gl/pMhMld

Saturated fat laden foods have not become healthy after a couple of best-seller books. http://goo.gl/gjzT8i

Healthy diet can be composed in many ways. Healthy diet can take a form DASH diet, paleolithic diet, low carbohydrate diet, Mediterranean diet, vegan diet, Nordic diet and so forth. It's the actual food choices that determine the health effects of a model.

"We need less debate about what diet is good for health, and much more attention directed at how best to move our cultures/societies in the direction of the well-established theme of optimal eating, for we remain mired a long way from it" Katz and Miller have aptly stated in their review on healthy diet models [2]

Katz and Meller could not be more right. If something is to blame, it is the very poor adherence to guidelines. For example, in Nordic countries <0,3% of the population has ideal diet and only 9-24% have somewhat healthy diet when dietary guidelines are set as benchmark [3]. As far as I know the situation is not better in UK, US or Germany.

In contrast to recommended diet, poor diet, ie. "Western diet pattern" has been associated with substantially increased risk of type 2 diabetes, coronary heart disease, obesity and cancer in many meta-analyses. Details can again be found here http://goo.gl/pMhMld

Are some diets are mass murder? Possibly. Junk food diet embraced in Western world is a potential suspect. Don't bark up the wrong tree.

1. Fardet A, Boirie Y. Associations between food and beverage groups and major diet-related chronic diseases: an exhaustive review of pooled/meta-analyses and systematic reviews. Nutr Rev 2014;72(12):741-62

2. Katz DL, Meller S. Can we say what diet is best for health? Annu Rev Public Health. 2014;35:83-103.

3. Nordic monitoring of diet, physical activity and overweight. First collection of data in all Nordic Countries 2011

Competing interests: No competing interests

17 December 2014
Reijo P Laatikainen
Dietician
Booston Oy Ltd, Viikinkaari 6, 00790 Helsinki, Finland