Scientists argue guidelines should consider diet-changing microbiome mechanisms
Research illustrates the commonalities between microbiome and nutritional disciplines in relation to diseases, physiological states, and experimental approaches, they write.
This offers “clear testament to the profound effects of diet on human health” and is further demonstrated by the escalation of chronic diseases in non-industrialised populations that transition to a Western-style diet, they say.
The reviewers therefore propose microbiome-targeted nutritional strategies and an experimental framework for “systematic incorporation of the gut microbiome into future nutrition research".
“We apply this knowledge to inform discussions of nutrition controversies and advance innovative dietary strategies.”
The comprehensive review, published in Cell Host & Microbe, discusses national dietary guidelines from a microbiome perspective and evidence that demonstrates interactions between host gut microbiome, diet, and physiological mechanisms.
A healthy diet is crucial for disease management and in controlling levels of non-communicable chronic diseases. Microbes in the gastrointestinal tract contribute significantly to the proper functioning of host metabolism and immunology.
As such, “it is crucial to identify health-promoting or detrimental foods and dietary patterns and translate the evidence into dietary guidelines”, the researchers say.
“Mechanisms by which the microbiome influences pathophysiology have been identified. These discoveries provide a strong scientific rationale to incorporate the gut microbiome in nutrition research and dietary guidelines.”
An evaluation of dietary guidelines from 17 countries (in Europe, North and South America, Asia, Africa, and Australasia) reveal that whole-plant foods are recommended in all cases but, despite promotion of health benefits, consumption is consistently low in industrialised countries where populations favour processed food.
Guidelines broadly recommend fruit and vegetables as the main component of a healthy diet, and plant-based protein foods were promoted by Canada, Brazil, and the UK.
Fish consumption was encouraged for its high protein content and favourable fatty acids, along with a Mediterranean-style diet.
National governments are, however, waking up to the interconnections and synergistic effects of individual foods and dietary patterns, which has prompted changes to dietary guidelines, notably in America and Canada.
“Interactions among foods are relevant for their effects on the gut microbiome, and there has been significant interest in how dietary patterns, especially those with established health benefits such as the Mediterranean diet, influence host health via microbiome compositional and functional changes.”
Regardless, there are persistent food controversies that could be resolved with better insight of host-microbe interactions, reviewers say.
Conflicting views on health outcomes from excessive red meat and dairy consumption remain, as well as differing opinions on the merits or pitfalls of low-fat versus low-carbohydrate diets.
While agreement between nutrition and microbiome disciplines largely validate current dietary guidelines, the authors argue that further “systematic incorporation of knowledge on the molecular foundations by which nutrients influence host-microbe interactions has the potential to enhance and innovate human nutrition”.
These include evolutionary considerations, targeted microbiome restorative strategies, and precision nutrition.
The reviewers conclude that microbiome outcomes should be embedded in all aspects of nutrition science to strengthen the evidence base for dietary guidelines.
“Nutritional microbiology studies have potential to holistically inform aspects of healthy eating and thus contribute to the solution of diet-related disease prevention and management.”
Source: Cell Host & Microbe
Published: DOI: 10.1016/j.chom.2022.04.016
‘Rethinking healthy eating in light of the gut microbiome’
Anissa Armet et al.