Globally, 107 million people are estimated to have an alcohol use disorder. Alcohol inhibits the absorption and usage of vital nutrients such as thiamin (vitamin B1), vitamin B12, folic acid, and zinc. Chronic alcohol abuse is associated with several neurological disorders, including Wernicke-Korsakoff syndrome (WKS). The deficiency of Thiamine, a vitamin essential for the metabolism and function of brain cells—is thought to be one factor contributing to the cognitive deficits and brain pathology characteristic of WKS. Excessive alcohol consumption may contribute to thiamine deficiency in several ways. Studies in human patients and animal models of WKS are attempting to identify brain structures affected by thiamine deficiency and to correlate them with the cognitive deficits observed in WKS patients. 

Thiamine or vitamin B1 is an essential vitamin that cannot be produced naturally in the human body. It is usually obtained from food sourced or dietary supplements and is absorbed by the small intestine. Thiamine stores may last up to 18 days, after which the excess would be excreted in the urine (1). Alcohol consumption had been deeply engraved into the current lifestyles of the world’s population, especially in the UK. Regular drinking habits have been evaluated to associate with the feeling of relaxation and the social norms of socialising to maintain friendships (2). With that, drinking has been justified as a choice and culture. Nonetheless, throughout the years, past studies have shown that alcohol consumption has led to various health complications and nutrient deficiency. 

Thiamine is an essential vitamin obtained from food or dietary supplements and is only stored for a limited duration of up to 18 days. The deficiency of thiamine happened to be very commonly correlated with alcohol dependence. This has become more of a concern to the community as an increase in excessive drinking has been reflected over the course of the COVID-19 pandemic due to elevated household stress levels (3). Thiamine is vastly associated with energy conversion and the coordination of the nervous systems. Therefore, if excessive alcohol consumption is prolonged, thiamine levels can deplete—potentially resulting in a wide range of clinical manifestations such as confusion, seizures, shortness of breath, brain disease, coma, etc. Moreover, mental disorders such as major depressive disorders and mood swings have also been highly associated with thiamine deficiency. 


Alcoholism is a chronic condition that can lead to a variety of physical and mental health problems, and thiamine plays a critical role in mitigating some of these negative outcomes. Alcoholism can interfere with the absorption and utilization of thiamine in the body, leading to a deficiency of this important vitamin. Thiamine is essential for the proper functioning of the nervous system and plays a key role in the metabolism of carbohydrates. It also helps to produce ATP, the primary energy source for the body’s cells. In individuals with alcoholism, thiamine deficiency can lead to a variety of serious conditions, including Wernicke-Korsakoff syndrome, which is characterized by confusion, memory loss, and other neurological symptoms. Thiamine deficiency can, moreover, cause cardiovascular problems, muscle weakness, and peripheral neuropathy.

The deficiency of this vitamin is vastly induced by alcohol’s role in interfering with thiamine absorption in the intestines and metabolism in the liver—both limiting the overall uptake of the body’s ideal thiamine requirements. Moreover, since alcohol is also a source of energy, heavy drinkers tend to have their appetites fulfilled as they obtain calories from alcohol alone; hence, the body continues to receive insufficient amounts of essential nutrients including thiamine (1). Even with appetite restored, people with alcohol dependence would opt for diets rich in carbohydrates and low in vitamins. 

Speaking of carbohydrate-rich diets, many of the food sources are highly processed and lack nutrients (4). For instance, originally stored in the bran of rice are B-complex vitamins: thiamine (B1), riboflavin (B2), nicotinic acid (B3), and pyridoxine (B6). Due to the high degree of food processing involved in turning brown rice into white rice, B-complex vitamins would be discarded alongside the rice bran. Since thiamine plays a key role in carbohydrate metabolism, a large uptake of carbohydrates without any thiamine replenishment will use up the thiamine stores—putting thiamine levels further at risk for deficiency.


In managing patients with an underlying history of alcohol dependency, the incorporation of thiamine-rich food into diets should be practiced. Additionally, support and alcohol detoxification regimens will usually be introduced to patients for efficient supplementation and significant health improvements. You should be able to consult with physicians of GPs regarding any clinical symptoms and struggles with alcohol dependency. Whole-blood tests may be recommended to assess thiamine status (5). 

Early prescription of thiamine therapy may also be encouraged since early treatment initiation may help prevent more severe neurological conditions from emerging or progressing. Thiamine supplementation by intravenous injection or by mouth has shown efficacy in treating people with alcohol dependency and withdrawal. It also acts as a prevention for serious conditions, such as Wernicke-Korsakoff syndrome, and improves overall health outcomes. For a more personalized dietary assessment and recommendations, be sure to check our website and reach out to one of our nutritionists. We will be more than happy to assist you on your journey to improving your quality of life.


  1. Osiezagha, K. et al. (2013) Thiamine Deficiency and Delirium. Available at: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3659035/ (Accessed 23 January 2023). 
  2. Parke, H. et al. (2018) “Understanding drinking among midlife men in the United Kingdom: A systematic review of qualitative studies,” Addictive Behaviors Reports, 8, pp. 85–94. Available at: https://doi.org/10.1016/j.abrep.2018.08.001 (Accessed 27 February 2023). 
  3. Hampton, T. (2022) Study holds warning on pandemic drinking, Harvard Gazette. Harvard Gazette. Available at: https://news.harvard.edu/gazette/story/2022/01/covid-related-drinking-linked-to-rise-in-liver-disease/ (Accessed 28 January 2023). 
  4. Zarei, I. et al. (2017) “Rice bran metabolome contains amino acids, vitamins & cofactors, and phytochemicals with medicinal and nutritional properties,” Rice, 10(1). Available at: https://doi.org/10.1186/s12284-017-0157-2 (Accessed 23 January 2023). 
  5. Jones, K.S. et al. (2020) “Erythrocyte transketolase activity coefficient (ETKAC) assay protocol for the assessment of thiamine status,” Annals of the New York Academy of Sciences, 1498(1), pp. 77–84. Available at: https://doi.org/10.1111/nyas.14547 (Accessed 30 January 2023). 

                 Article reviewed by Cosimo Simeone — Scientifically written by Angeline Lee, 

                                     Division of Medicine at University College London —

                                            Updated on March 7, 2023

Write a Reply or Comment

Your email address will not be published. Required fields are marked *