Magnesium daily requirement: 350 mg for adults, 300 mg for women, and increase for athletes. Long-term chronic diarrhea causes excessive excretion of magnesium, which can lead to magnesium deficiency. Magnesium deficiency mainly manifests restlessness, muscle twitching, loss of appetite, and convulsions in young children. Excessive intake of magnesium can cause vomiting, diarrhea, difficulty breathing, and impaired kidney and bladder function.