Interaction of alcohol’s direct toxic effects with malnutrition. In alcoholics, alcohol often replaces other nutrients (e.g., carbohydrates or proteins), resulting in insufficient intake of those nutrients (i.e., primary malnutrition), particularly because, under certain conditions, the calories provided by alcohol cannot be used effectively by the body—that is, they are “empty” calories. In addition, alcohol has direct toxic effects on the gastrointestinal tract and liver, leading to impaired digestion, reduced absorption of nutrients into the blood, and impaired utilization or increased degradation of those nutrients. These effects are referred to as secondary malnutrition and can contribute to the progression of liver damage.