Our modern-day lifestyles within Westernised countries differ radically from our hominid hunter-gatherer ancestors. Accordingly, our genetic make-up is maladapted to our modern-day environs and lifestyles. Furthermore, our gut microbiota, that co-evolved with us over millions of years, and upon which our health utterly relies, have likely changed radically through our evolutionarily highly unusual modern-day lifestyles, a major component of which is our diet.
Our modern-day diets within European countries and North America are impoverished of fibre. One obvious factor relates to the highly processed diets that many people adopt. Underlying explanations for such a radical shift in dietary consumption in recent decades are likely multi-factorial. These include an abundance of cheap and highly processed food supplies within our supermarkets and a bias for such food production from many food companies. Further contributing factors include advertising for processed foods, cultural and societal changes, convenience of highly processed diets (with a reduced need for cooking from raw ingredients), highly abundant ‘fast-food’ outlets and the hedonic and potentially addictive effects of the unnatural sugar–fat combination that typifies many highly processed foods. One problem with highly processed foods is that their fibre content tends to be lower than meals prepared from raw ingredients. Rauber and colleagues reported on the consumption of ultra-processed foods within the UK, based on cross-sectional data from the UK National Diet and Nutrition Survey between 2008 and 2014. Based on a four-day food diary, it was shown that just 30.1% of calories originated from unprocessed or minimally processed foods, with the majority of calories (56.8%) coming from ultra-processed foods. Furthermore, whilst consumption of ultra-processed foods was associated with increased intake of carbohydrates, free sugars, saturated fats and sodium, consumption of ultra-processed foods also inversely correlated with dietary fibre intake. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7589116/#sec5-nutrients-12-03209title (OPTIMISATION OF DIETARY FIBRE FOR THE FUTURE 6.0)