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With suicide rates continuing to climb, the challenges around suicide prevention often seem insurmountable. Yet research, clinical experience and case studies highlight how suicide is often a manifestation of functional imbalances, disturbances that can be addressed and treated. As the following case study clearly documents, some cases of suicidal ideation can be rooted in nutritional deficiencies. As Psychiatry Redefined has been teaching for years, by recognizing and addressing the biological factors that cause or contribute to suicide, we can save lives.

A Case Report

A Case of Thiamine Deficiency

A 58-year old woman was hospitalized with severe depression symptoms and a recent suicide attempt (Ishida 2023). She was currently being treated for endometrial cancer with pelvic dissemination and lung metastasis. After the suicide attempt, upon examination, she was suspected of having major depressive disorder.

Her symptoms included heart palpitations, dyspnea, anorexia and insomnia. Due to her poor dietary intake, an infusion of thiamine, or vitamin B1, was administered.

To the surprise of the treating staff, one hour post infusion, her suicidal ideation completely resolved. In addition, the palpitations, dyspnea, anorexia and insomnia all improved. Based on the outcome, thiamine deficiency was believed to have been causing the symptoms of severe depression with suicidal ideation–a simple nutritional deficiency with symptoms that reversed rapidly once addressed appropriately.

Thiamine and Beriberi

Thiamine deficiency, or beriberi, can cause peripheral neuropathy, heart failure, vertigo, double vision and memory loss (Wiley 2022). Thiamine is a required nutrient for energy production in the brain and its absence can cause the build up of toxic metabolic byproducts. This in turn can manifest as Woernicke’s encephalopathy.

While alcohol is the most common cause, other factors, including dietary insufficiency or repeated vomiting can also predispose to the condition. The most common symptoms are mental status changes, weakness or paralysis of the eye muscles and an uncoordinated gait. Unfortunately, numerous cases do not present with classical symptoms and approximately 85% are only identified after death from the condition (Torvik 1991).

For patients with beriberi, mental status changes can include delirium, confusion, reduced alertness, irritability and altered consciousness (Oudman 2021). While increased risks of thiamine deficiency have been documented among patients with mental illness (Estevez 2023), they are often considered secondary to poor eating habits and not a primary cause or factor in the psychiatric diagnosis.

Considering how poorly beriberi is even recognized and treated in patients, it would seem likely that additional cases are being misidentified as depression, or other mental illness, with the underlying thiamine deficiency untreated.

Biological Origins of Suicidal Behavior

This case dramatically highlights how biochemistry can underlie mental illness. Suicidal thoughts can be a manifestation of brain circuitry gone awry from nutritional deficiencies or other biological factors. As we’ve been teaching in our suicide prevention course for years, research shows that suicide often has biochemical underpinnings.

When biological imbalances and deficiencies are identified, suicide can become a more manageable condition – reducing risks, improving outcomes, and saving lives. 

Thiamine is one component in a list that includes cholesterol, lithium, inflammation, folate, vitamin D and omega-3 fatty acids which can all help to mitigate suicide risks when assessed and addressed appropriately. My own personal experience with thousands of patients has shown the power of a Functional approach for suicide prevention. With the proper tools, we can make a difference. With proper treatment, we will save lives.

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Estevez TP, Casasnovas CE, Aslanova M, Rizk D, Safin DS. Diagnosis of Wernicke’s Encephalopathy in Patients With a Psychiatric History: A Case Series and Literature Review. Prim Care Companion CNS Disord. 2023;25(4):22nr03447. Published 2023 Jul 20. doi:10.4088/PCC.22nr03447

Ishida M, Sato S, Sato I, et al. What can cause cancer patients to attempt suicide? Thiamine deficiency mimicking the symptoms of major depressive disorder [published online ahead of print, 2023 Jul 27]. Palliat Support Care. 2023;1-4. doi:10.1017/S1478951523001128

Oudman E, Wijnia JW, Oey MJ, van Dam M, Postma A. Wernicke-Korsakoff syndrome despite no alcohol abuse: A summary of systematic reports. J Neurol Sci. 2021;426:117482. doi:10.1016/j.jns.2021.117482

Torvik A. Wernicke’s encephalopathy–prevalence and clinical spectrum. Alcohol Alcohol Suppl. 1991;1:381-384.

Wiley KD, Gupta M. Vitamin B1 (Thiamine) Deficiency. In: StatPearls. Treasure Island (FL): StatPearls Publishing; July 17, 2023.