Diarrhoea is the most common problem among people with HIV. HIV itself, along with malnutrition and some drugs, can cause diarrhoea. If water is not replaced as quickly as it is lost from the stool, it will lead to dehydration. Diarrhoea also weakens the gut, making it less able to absorb food and drugs. The vicious cycle carries on as the less food and drug absorbed, the more severe diarrhoea might become.
Nevertheless, diarrhoea will go away naturally if it is well managed. People often stop eating as they experience discomfort - but you must eat more than usual as you are not absorbing as much. Carefully wash and cook your food thoroughly to reduce the risks of further infection.