How Long Does It Take to Change Dietary Habits?

The diets in these countries also shifted over time towards more westernized diets, and maybe that could also relate to the effects of not seeing differences between countries here. How long do we have to provide these dietary changes to really induce a change, for example, in the gut microbiome? Whether that needs long-standing patterns or short-term interventions? That's not really known yet. So, indeed, we need intervention studies to reproof what we see here.