Agreement: I AgreeBody: Dear Editor, Chronic inflammation in young people is correlated with a range of disease including obesity, type 2 diabetes mellitus, anxiety and depression [1]. A sub-optimal microbiome due to changes in diet is thought to be an important factor. A sub-optimal microbiome allows bacteria such as Staphylococcal aureus and the periodontal pathogens to become established within the mucosa (intra-mucosal microbiota). These bacteria have evolved genetic mechanisms to evade immune mediated rejection. The result is low grade cell damage leading to low grade chronic inflammation. S. aureus secretes superantigens which cause non-specific proliferation of T lymphocytes and the secretion of pro-inflammatory cytokines which cause further cell damage and a further increase in chronic inflammation. The resulting cell damage and the inflammatory response together contribute to a wide range of disease both mental and physical. We need large scale studies to assess S. aureus mucosal carriage throughout the age range, correlate this with disease and then assess how carriage can be reduced by dietary change. The composition of mother’s milk has evolved over millions of years to provide the infant with nutrition, immune information and to establish an optimal microbiome. But the consumption of lactose fermenting bacteria in cow’s milk has decreased in the UK and the USA over the last 50 years. This could be the missing ingredient in the modern diet and we need to see if the regular consumption of yoghurt can re-establish an optimal microbiome and reduce both S. aureus carriage and chronic inflammation. Reference: 1. Morris JA, Rigby RJ, Wray M, Taylor AM. The microbiome and the entropy paradox: an evolutionary perspective. Food & Nutrition Journal 2024;9:294 https://www.researchgate.net/publication/379311083_The_Microbiome_and_th... No competing Interests: YesThe following competing Interests: Electronic Publication Date: Sunday, September 21, 2025 - 10:41AI use: No, I have not used AIHighwire Comment Subject: What MAHA’s new Making Children Healthy Again report says—and what it doesn’tWorkflow State: ReleasedFull Title: Intra-mucosal microbiota: the key to chronic inflammation in the young Highwire Comment Response to: What MAHA’s new Making Children Healthy Again report says—and what it doesn’tCheck this box if you would like your letter to appear anonymously:: Last Name: MorrisFirst name and middle initial: JamesEmail: jamorris@doctors.org.ukAddress: Carnforth, Lancs Occupation: consultant pathologist (retired)BMJ: Additional Article Info: Rapid response