We tend to associate fasting with giving up food. However, there may be health considerations, so if you have any concerns, are on regular medication or are diabetic it would be wise to consult your doctor before beginning any kind of fast from food. Even if you know you can fast safely from food, remember some simple safety points:
Drink plenty of fluids throughout the day. You may prefer to stay away from certain drinks such as tea/coffee, or fruit juices etc., but it's not advisable to fast from liquids altogether. Drinking several large glasses of still water will allow you to keep your fast while keeping healthy.
Break your fast carefully. The longer the fast, the more careful you need to be when re-introducing food. Make your first meal a light one.
Be careful about fasting if you need to do a lot of driving, or operate potentially dangerous machinery, as you may feel tired or even a little weak.
Commit your fast to the Lord. Remember that fasting is not about torturing yourself, or blackmailing God - it is a tool to focus your mind as you petition God about our nation.