KS is caused by a lack of thiamine in the brain. Thiamine (vitamin B1) is absorbed in the small intestine and is used in many places in the body. It is a water-soluble vitamin, so the body does not store it in large amounts, which means we need thiamine on a regular basis. Substances such as alcohol and certain medications can inhibit the absorption process, putting a person at risk for several issues, including weight loss, muscle weakness, cardiac issues, peripheral neuropathy, brain swelling (Wernicke's encephalopathy), and KS. Anything that causes a significant impact on nutrition or the small intestine can result in a thiamine deficiency, including (but not limited to) excessive vomiting, starvation/malnutrition, and bariatric surgery. Certain parts of the brain rely on thiamine for cell metabolism, so these parts may sustain damage if thiamine is depleted. There is currently no way to predict if, how, or when a person can develop KS. While risk factors include things like alcohol use, diet, and genetic factors, some can tolerate low or varying thiamine levels, while others develop KS very quickly.