References: Diet & the gut

The key studies and reviews behind these pathways – organised by page, so you can see exactly what each claim on the site is based on.

Turnbaugh, P.J., Ley, R.E., Hamady, M., Fraser-Liggett, C.M., Knight, R. & Gordon, J.I. (2007). “The Human Microbiome Project.” Nature, 449(7164), 804–810. The 2007 project this page describes as the major turning point in mapping the gut’s trillions of bacteria in detail.
Carabotti, M., Scirocco, A., Maselli, M.A. & Severi, C. (2015). “The gut-brain axis: interactions between enteric microbiota, central and enteric nervous systems.” Annals of Gastroenterology, 28(2), 203–209. The evidence behind this page’s account of the gut producing much of the body’s serotonin and the vagus nerve carrying signals between gut and brain.
Jacka, F.N., O’Neil, A., Opie, R., et al. (2017). “A randomised controlled trial of dietary improvement for adults with major depression (the ‘SMILES’ trial).” BMC Medicine, 15, 23. A landmark randomised trial supporting this page’s claim that dietary pattern is associated with mood, among the more solid human evidence in a field otherwise dominated by animal studies.
Liu, R.T., Walsh, R.F.L. & Sheehan, A.E. (2019). “Prebiotics and probiotics for depression and anxiety: A systematic review and meta-analysis of controlled clinical trials.” Neuroscience & Biobehavioral Reviews, 102, 13–23. The evidence behind this page’s caveat that probiotic research remains too mixed and short-term to confidently recommend a specific product over general dietary pattern.