For the last three months I am taking a litre of warm water in empty stomach and after half an hour I drink a glass of warm water mixed with the juice of a whole lemon and a teaspoon full of honey everyday. Since then my problem of hyperacidity and heartburn is reduced and the usual headache related with such problems is vanished. And my appetite is also increased. Now I am feeling quite ok. But my question is prolonged taking of a whole lemon everyday in empty stomach is safe? Are there any side effect for maintaining this practice for a whole life? Please tell me the usefulness of this practice.