3 Day Fast

While on a 3-day fast, you can expect to lose around one pound of body weight per day. If you have been eating a diet high in salt and processed foods, however, you might lose as much as three pounds per day. However, not all of this weight lost is from body fat.

Much of the weight you lose during a 3-day fast is actually water weight. Since you are in a state of simulated starvation, your body will also turn to its structures - not just fat - for sources of energy. Rapid weight loss results in a reduction in your muscle mass as well. If you want to lose weight mostly from fat, while keeping your muscles in shape, a slower method of weight loss would be preferable.²

One of the benefits to short-term fasting is that it causes your body to undergo a process known as autophagy. During autophagy, your cells break down old and possibly damaged components to recycle as energy or new building blocks. Research suggests that enhanced autophagy can increase life expectancy and protect against certain diseases like cancer and Alzheimer’s disease.^{1, 3}

You should always work under the guidance of your doctor if you are planning to fast for longer than three days. Even for three days or less, it might be a good idea to talk to your family doctor or a nutritionist. There are several health conditions that could make fasting dangerous, such as:^4-6

• Kidney disease
• Diabetes (type I or type II)
• Eating disorders
• Gastroesophageal reflux disease (GERD) or heartburn
• Gout
• Pregnancy
• Old age
• Low blood pressure (hypotension)

Do:

• Prepare yourself by eating lightly or fasting part of the day beforehand
• Drink plenty of water, since you normally get a lot of your daily water intake from food and caloric beverages
• Take it easy and get plenty of rest
• Stop fasting if you feel dizzy, faint, or experience other symptoms
• Break your fast with a light meal, such as a smoothie

Don’t:

• Exercise more than gentle walking
• Eat a large, heavy meal immediately after finishing your fast
• Fast if you are a child or teenager