The quote making up the title of this post comes from the case report described by Albino J Oliveira-Maia and colleagues  talking yet again about how coeliac disease - the archetypal autoimmune condition where dietary gluten is the baddie - may have effects well beyond just the physical.
Describing the experiences of a woman who was admitted to a psychiatry inpatient unit on the basis of "suicidal behaviours" who also "developed an agitated catatonic state", a mix of "antidepressants, anxiolytics, antipsychotics and electroconvulsive therapy" seemingly did very little to her state at/during admission we are told. Further, some diagnostic work-up beyond just her psychiatric features "allowed for the diagnosis of coeliac disease" and instigation of a gluten-free diet - the primary management option for coeliac disease - seemed to have something of a 'significant' effect on her psychiatric well-being as per that opening quote.
Am I particularly surprised by all of this? No. Regular readers will know that I've previously talked about gluten and psychiatry quite a few times on this blog (see here and see here for example) and there is other research out there in the peer-reviewed domain pertinent to discussions . Without trying to over-generalise a case report to anything further, there are a number of notable peer-reviewed papers that have suggested that diet can affect psychiatry and this addition merely adds to the haul.
If I did perhaps have to go into further detail on how something like suicidal behaviours might link into gluten and coeliac disease (CD) I would perhaps draw your attention to how gluten does seem to be a 'mood affector' when it comes to at least some cases of CD (see here) and the link between something like depression and suicidality. I'm sure however that this is not the final word on any such link and please, don't generalise with any sweeping suggestions about how all depression is somehow caused solely by gluten. Depression is a very complicated entity.
More research is of course indicated but I do wonder how many more case reports on previously unidentified coeliac disease (or non-coeliac gluten sensitivity even?) and similar psychiatric symptoms there may be out there? Time for more screening of vulnerable populations perhaps...
 Oliveira-Maia AJ. et al. Case of coeliac disease presenting in the psychiatry ward. BMJ Case Rep. 2016 Dec 21;2016. pii: bcr2016216825.
 Ludvigsson JF. et al. Increased suicide risk in coeliac disease--a Swedish nationwide cohort study. Dig Liver Dis. 2011 Aug;43(8):616-22.
Oliveira-Maia AJ, Andrade I, & Barahona-Corrêa JB (2016). Case of coeliac disease presenting in the psychiatry ward. BMJ case reports, 2016 PMID: 28003229