Refeed After 3 Day Fast: 7 Rules To Follow & What To Eat

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The most important part of fasting is actually fasting, right? Absolutely not! The most important part of fasting is actually the refeeding process following the fast because if we’re not executing the refeed properly we can increase our risk of adverse health effects and intense discomfort.

What Should You Eat After A 3 Day Fast? After a 3 day fast, we should start by introducing liquids, and gradually transition to solid food as tolerated.

Foods that are low in refined sugar, low in sodium, and are easy to digest should be prioritized to avoid overwhelming the digestive system.

After reading this article you’ll learn:

What Happens To Your Body After A 3 Day Fast

After a 3 day fasts, our bodies will have depleted all our glycogen stores, which is typically our body’s primary source of energy. So instead, we will be breaking down fat and muscle for energy.

In the early stages of fasting, we will be burning the glycogen fuel that our body has stored up in the muscles and liver, but once we run out of stored glycogen our body will have to rely on its tissues to produce the energy necessary to perform basic bodily functions. 

The process of using our tissue as an energy source is called “Autophagy”.

This process can be beneficial for those hoping to burn fat that their body has stored, however, there is also the chance that our body will have to tap into our muscle tissue for energy.

When we start breaking down muscle tissue for energy, we’re doing more harm than good.

Muscle is valuable to have because the more muscle we have, the higher our metabolism will be, which means that just by having muscle we’ll burn more calories throughout the day.

So when we start breaking down muscle for energy, we slow down our metabolism and burn fewer calories throughout the day. This is not the move if our goal is to lose weight and/or fat mass. 

Stored fat tissue will typically be used first for energy before muscle tissue; therefore the more body fat we have, the less likely it is that we will have to tap into our muscle tissue but it is something to keep in mind if we’re someone who doesn’t have much fat to rely on.

Refeeding After A 3 Day Fast: 7 Rules To Follow

Following a 3 day fast we need to follow these 7 rules:

  1. Replace Lost Electrolytes
  2. Keep Your Calorie Intake Low For 1-2 Days
  3. Start With Liquids Before Solids
  4. Avoid Overhydration
  5. Prioritize Protein & Fats Over Carbohydrates Initially
  6. Take Daily Supplements
  7. Avoid Alcohol
  • If you’ve fasted for 5 days (not 3 days), then check out my article: Refeed After 5 Day Fast. My recommendations are slightly different for longer fasting periods.

1. Replace Lost Electrolytes

When fasting for long periods we throw off our electrolyte balance, and if we start consuming food again without replenishing these electrolytes we can increase our risk of refeeding syndrome.

Refeeding syndrome is a condition that occurs when our body’s balance of fluid and electrolytes is thrown off. 

In mild cases, we could expect excessive swelling (edema) and muscular fatigue. However, in more severe cases it can result in respiratory dysfunction, neurological symptoms, and cardiovascular issues.

Refeeding syndrome occurs when the level of electrolytes (magnesium, potassium, and phosphorus) in our blood becomes dangerously low. This happens when we go from a fasted state to all of a sudden consuming lots of food – particularly carbohydrates.

A large intake of carbohydrates immediately following a fast is the main culprit of refeeding syndrome because when we eat carbs our body releases insulin to signal to the cells in our body to start pulling the sugar from these carbs, and electrolytes from the bloodstream to the cells. 

This is dangerous because our level of electrolytes would already be low from fasting, so when the insulin gives the signal to the cells to start pulling it from the bloodstream, it leaves us with dangerously low levels of electrolytes, which causes all the potential respiratory, cardiac, and neurological issues.

To reduce our risk of refeeding syndrome we should replace lost electrolytes as soon as possible following the fast. This can be done by taking an electrolyte supplement.

We should also limit the number of carbs we eat initially, but more on that later….

2. Keep Your Calorie Intake Low For 1-2 Days

After fasting we need to build back up slowly to avoid digestive upset and to reduce the risk of refeeding syndrome, for these reasons we should limit our intake to 50% of our normal intake initially.

To avoid overwhelming the digestive system and to prevent insulin spikes, it is recommended to keep calories at 50% of our normal intake, which is around 12.5 to 17.5 calories per kilogram of bodyweight.

I recommend sticking to this level of intake for at least 2 days following a fast.

For example: If I weigh 71kg, then my calorie range for the first 2 days of refeeding would be 888 to 1243 calories.

I recommend sticking to the lower end of this calorie range on the first day of refeeding, and perhaps moving towards the higher end of the range for the second day of refeeding.

If after 2 days we’re symptom-free, then we can gradually increase our intake back up to a normal range. Typically we could expect to be eating back at our normal calorie range after 3 to 4 days of refeeding.

3. Start With Liquids Before Solids

After a fast, our ability to digest foods will be slightly impaired because the digestive processes will have halted, therefore starting with liquids rather than solids gives the body a chance to catch up.

liquid intake

I recommend starting with liquid calories for the first 1 to 2 days after a fast to initiate the refeeding process because liquids are easier to digest than solid foods as they require fewer digestive enzymes to break down the food.

Our digestive enzymes (the things that help break down our food) for each macronutrient will be decreased because when we’re not consuming carbs, fats, and proteins their corresponding digestive enzymes will decrease.

After all, the body has no use for them while we’re fasting.

It will take some time for these digestive enzymes to ramp back up, so we can help them out initially by sticking to easily digestible liquids, which will also help to prevent digestive upset.

4. Avoid Overhydration

We should also limit our water intake when we’re refeeding because our concentrations of electrolytes in the blood will already be diminished, and if we overhydrate then we will dilute our blood even further.

We will not require as much water as we typically would when we’re refeeding because we will already be consuming more liquids for easier digestion, which will give us a solid amount of fluid already.

We should keep our water intake relatively low to avoid overhydration, which would increase our risk of refeeding syndrome.

5. Prioritize Proteins & Fats Over Carbohydrates Initially

When we’re refeeding we should prioritize more proteins and fats rather than carbs because they do not spike insulin the way that carbohydrates do.


It’s important to use most of our calorie allotment while refeeding towards proteins and fats.

I recommend consuming 0.4 to 0.75 grams of protein per kilogram of body weight to ensure that we’re getting enough protein to stop breaking down muscle tissue and start doing damage control.

For example: If I weigh 71kg then I should be consuming at least 29 to 53 grams of protein while my calories are at 50% of my normal intake.

Once we’ve our protein covered our next priority is our fat intake, simply because it does not spike insulin and therefore does not affect our electrolyte balance as carbohydrates do. 

Carbohydrates can still be consumed but I recommend keeping them relatively low and sticking to carbohydrates sources that are unprocessed, easily digestible, and ideally low FODMAP.

Low FODMAP foods are foods that do not ferment in the gut and contain insoluble fiber. These types of carbs are recommended initially because they can help prevent symptoms of Irritable Bowel Syndrome (IBS) which tend to be experienced after a fast when refeeding.

We don’t need to stick to Low FODMAP foods for long, on day 3 of refeeding we can start including all types of carbohydrates again because foods that ferment are important for our digestive system when we’re back to normal eating.

6. Take Daily Supplements

It is recommended to take an electrolyte supplement while fasting to reduce our risk of refeeding syndrome, or at least supplement them immediately after. We should also consider a digestive enzyme while our digestive system reboots.

We should be taking supplements the entire time that we’re fasting because it’s dangerous to let certain nutrients (electrolytes) drop below a certain level. 

However, if we didn’t supplement during our fast then it’s crucial to supplement immediately after fasting before ramping up our food intake.

Another beneficial supplement that we could incorporate is a digestive enzyme that we could take with our meals to help with digestion while our body re-adjusts and tries to ramp back up after not having to produce its digestive enzymes while we were fasting.

7. Avoid Alcohol

We must avoid alcohol altogether when we’re refeeding from our fast because our body will not be able to metabolize the alcohol like it normally would when we’re well-fed, and it can lead to health complications.

If we were to consume alcohol while underfed we could experience extreme digestion issues because alcohol makes digestion harder, and our digestive system will already be impaired from fasting alone.

In addition, consuming alcohol when refeeding increases our risk of alcoholic ketoacidosis because our body will be in a state of starvation and not prepared to handle the alcohol even if it’s not in excess.

Foods To Avoid After A 3 Day Fast

After a 72 hour fast we should avoid:

  • Processed Foods
  • Alcohol
  • Foods that are difficult to digest

Avoid Processed Foods

Processed Foods

Processed foods contain more refined sugar and sodium, both of which are counterproductive when we’re refeeding because they both increase our risk of refeeding syndrome.

Avoid Alcohol

Alcohol is one of our worst enemies when we’re refeeding because it impairs our digestion and increases our risk of alcoholic ketoacidosis which can cause abdominal pain, irregular breathing, nausea, vomiting, and dizziness.

Avoid Foods That Are Difficult To Digest

We should avoid foods that are more difficult to digest like High FODMAP foods (dairy, garlic, onion, wheat, legumes) when we first begin the refeeding process because they can cause symptoms of IBS such as abdominal pain, bloating, diarrhea and/or constipation.

Refeed Meal Plan Following A 72 Hour Fast

The following is an example meal plan for a 71kg individual:

Day 1 of Refeed:

Column 1Column 2
Supplement:Electrolyte Supplement
Calorie target (up to 12.5 cals/kg BW):888 calories
Protein target (0.4-0.75 grams/kg BW):29-53 grams
Sodium:Under 1000mg
Water Intake: Minimal
Food Composition:Liquid

Sample Day

Meal 1:

  • 2 cups low-sodium bone broth

Meal 2:

  • Avocado Protein Shake (blend: ½ avocado, 1 scoop protein, water)

Meal 3:

  •  2 cups low-sodium bone broth + 1 tbsp olive oil

Day 2 of Refeed:

Column 1Column 2
Supplement:Electrolyte Supplement
Calorie target (17 cals/kg BW): 1207 calories
Protein target (0.4-0.75 grams/kg BW):29-53 grams
Sodium:Under 1000mg
Water Intake: Minimal
Food Composition:50% liquid, 50% solid

Sample Day

Meal 1:

  • 2 cups low-sodium bone broth

Meal 2:

  • 4 oz steak
  • 1 cup steamed broccoli
  • ½ tbsp olive oil

Meal 3:

  • 2 Eggs
  • 1 cup steamed Spinach + 1 tbsp olive oil

Meal 4:

  • Strawberry Avocado Protein Smoothie
    • blend 1 cup strawberries, ½ avocado, 1 scoop protein, water

Day 3 of Refeed:

Column 1Column 2
Supplement:Electrolyte Supplement
Calorie target (at least 20 cals/kg BW):at least 1420 calories
Protein target (1.5-2 grams/kg BW):107-142 grams
Sodium:Under 2000mg
Water Intake: Moderate (~0.5-1L)
Food Composition:solids

Sample Day

Meal 1:

  • 2 eggs
  • 1 oz brie or feta
  • 1 cup strawberries

Meal 2:

  • 4oz steak
  • 1 cup steamed broccoli
  • ½ cup cooked potatoes
  • Roasted with 1tbsp olive oil, or mashed with 1 tbsp butter

Meal 3:

  • 4 oz salmon (or other fatty fish)
  • 1 cup steamed spinach + ½ tbsp olive oil
  • ¼ cup quinoa

Meal 4:

  • 1 egg
  • ½ avocado

Day 4 of Refeed:

Back to normal eating habits!!

Final Thoughts

Being cautious after a fast and slowly building back up to normal eating habits is going to produce the best results and reduce your risk of adverse health effects!

Check out our other refeeding articles:

About The Author

Amanda Parker

Amanda Parker is an author, nutrition coach, and Certified Naturopath.  She works with bodybuilders, Olympic weightlifters, and powerlifters to increase performance through nutrition and lifestyle coaching.

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