In clients with alcoholism, which vitamin deficiency is most common?

• A. Riboflavin
• B. Thiamine
• C. Vitamin C
• D. Vitamin D

Answer: (B)

In alcoholism, thiamine (vitamin B1) deficiency is the most common nutritional problem because alcohol lowers intake, impairs absorption, disrupts liver storage, and increases urinary loss. Thiamine is a crucial cofactor for enzymes that convert carbohydrates into energy, which is especially important for brain cells that depend on glucose. When thiamine is lacking, brain energy production falters, leading to neurological symptoms. If not treated promptly, this can progress to Wernicke's encephalopathy, characterized by eye movement problems, gait ataxia, and confusion, and can advance to Korsakoff syndrome with severe memory impairment. Because thiamine deficiency can be life-threatening, it should be addressed quickly, and in acute care settings, thiamine is given before any glucose-containing therapy to prevent worsening of symptoms. Other vitamins such as riboflavin, vitamin C, or vitamin D can also be deficient in alcoholics, but they are less common or less immediately critical than thiamine.