To prevent headaches, hunger pangs, fatigue, and other side effects, drink plenty of water. Pound a big glass right when you wake up and drink throughout your fast.
Caffeine can also help, so sip on black coffee or green tea. If you're fasting for longer periods of time, putting a little pink Himalayan sea salt in your water can also prevent feeling foggy-headed. Going for a walk or light stretching can also make you feel better.
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