Knowledge for better food systems

Can we say what diet is best for health?

This paper provides a schema for categorizing all diets as either: low carbohydrate; fat, low glycemic; Mediterranean; mixed, balanced; Paleolithic; or vegan.  The researchers emphasize that the aim of the research is not to recommend one particular diet over another, but rather to highlight how disease prevention and increased public health is best realised.

The authors state that following the eating recommendation provided by Michael Pollan: “Food, not too much, mostly plants” gives a good foundation for this realising this goal. The authors further argue that using tools that help to guide discrete food choices made at a particular time can be helpful to achieving long term change. Ultimately, they conclude ‘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’.


Diet is established among the most important influences on health in modern societies. Injudicious diet figures among the leading causes of premature death and chronic disease. Optimal eating is associated with increased life expectancy, dramatic reduction in lifetime risk of all chronic disease, and amelioration of gene expression. In this context, claims abound for the competitive merits of various diets relative to one another. Whereas such claims, particularly when attached to commercial interests, emphasize distinctions, the fundamental of virtually all eating patterns associated with meaningful evidence of health benefit overlap substantially. There have been no rigorous, long-term studies comparing contenders for best diet laurels using methodology that precludes bias and confounding, and for many reasons such studies are unlikely. In the absence of such direct comparisons, claims for the established superiority of any one specific diet over others are exaggerated. The weight of evidence strongly supports a theme of healthful eating while allowing for variations on that theme. A diet of minimally processed foods close to nature, predominantly plants, is decisively associated with health promotion and disease prevention and is consistent with the salient components of seemingly distinct dietary approaches. Efforts to improve public health through diet are forestalled not for want of knowledge about the optimal feeding of Homo sapiens but for distractions associated with exaggerated claims, and our failure to convert what we reliably know into what we routinely do. Knowledge in this case is not, as of yet, power; would that it were so.


Katz, D.L. & Meller, S., 2014, Can We Say What Diet Is Best for Health?, Annu. Rev. Public Health, 35:83–103, doi:10.1146/annurev-publhealth-032013-182351

Read the full paper here.

See further resources on healthy diets on our website.

You can read related research by browsing the following categories of our research library:

Add comment

Member input

Plain text

This question is for testing whether or not you are a human visitor and to prevent automated spam submissions.


Will Nicholson's picture
Submitted by Will Nicholson on

In my opinion the Nuval scores correlate well with measures of sustainability such as carbon footprint, water footprint, ecological footprint, making this a good place to start for both healthy and sustainable eating habits.  Not sure how well the correlation works for highly processed foods though, and from a health perspective, moving people from processed foods to real food is the biggest challenge maybe?  Make some progress in that and more sustainable diets would be easier to achieve I think, but trying to get people to eat less processed food as well as eat sustainably (which loosely translate as "cook more at home, and eat less meat, more sustainable produce") is asking for 2 behaviour changes at the same time.




While some of the food system challenges facing humanity are local, in an interconnected world, adopting a global perspective is essential. Many environmental issues, such as climate change, need supranational commitments and action to be addressed effectively. Due to ever increasing global trade flows, prices of commodities are connected through space; a drought in Romania may thus increase the price of wheat in Zimbabwe.

View global articles


Doc Type