Alcohol can also react with stomach acid. Both of these will cause nausea and vomiting. In some cases, excessive alcohol consumption can also cause bleeding in the digestive tract. Eating disorders. An eating disorder is when a person adjusts their eating habits and behaviors based on an unhealthy body image. It can cause nausea and vomiting. Bulimia is an eating disorder in which a person induces vomiting deliberately to purge the stomach of any consumed food. People with anorexia may also feel nausea due to starvation and excess stomach acid.