What is Fasting? Is it a Safe Way to Lose Weight?

person stepping on a scale Fasting is when you consume very little or no food and drink for a period of time. There are many different types of fasting. Some fasts allow you to have small amounts of liquids and some allow small amounts solid foods. 

Should I fast to lose weight? 

No. When you fast, your metabolism (the rate that your body burns energy) slows down.  A slower metabolism means that when you go back to your usual way of eating, you are likely to gain weight. After you fast, you will also feel hungrier and be more likely to overeat. Fasting for long periods of time is also not safe and can be life-threatening.  When you fast for a long time, you may:

  • Become dehydrated
  • Get headaches
  • Become weak and dizzy
  • Be low in nutrients
  • Lose muscle
  • Have lower immune function

Bottom line

Before you begin a weight loss program, speak with a health care professional.  Ask your doctor to refer you to a Registered Dietitian to discuss a healthy approach to weight management. 

Last Update – December 11, 2018

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