First, you’ve prepared for a fast. (Pats on the back for saying no to happy hour after work.) Then you’ve actually gone through with the fast, conquering hunger pangs like you were getting paid, transcending your physical desires for a higher purpose. Go you! 

Then…

Well, you just eat and get on with your brand-spankin’-new life, right?

Turns out, breaking a fast is more than just cramming something delicious into your mouth when you’ve finally hit your eating window. This final phase is just as much a part of fasting as the preparation phase or even fasting itself. If you gloss over it, you could potentially reverse the benefits you’ve worked hard to earn, and you could also harm yourself.

So in this article, we’ll show you how to break a fast in a way that will amplify your results while keeping you safe and healthy!

We’ll cover the following topics:

• how long this ‘refeeding’ phase should last
• what your first meal should look like
• what to expect after you’ve broken your fast

How long should the refeeding phase last?

The refeeding phase is defined as the period after you’ve broken a fast in which you eat a modified diet.

This is a necessary part of fasting because fasting for just a few days can alter the hormones that regulate the amount of digestive enzymes and stomach acid available to help break down food.    

Studies in animals demonstrate a significant reduction of enzymes from the pancreas and intestines after as little as 36 hours of fasting, but return to normal within 24 hours of refeeding.^[1][2]  A small trial of 12 obese individuals also showed a significant reduction in digestive enzymes after 10 days of fasting.^[3]

Digging into a ‘steak’n’tater’ dinner under these conditions, then, would not only result in you carrying a lead brick in your stomach for the better part of a day, but it would stress your body and potentially interrupt the rejuvenative effects of fasting.

The rejuvenating effects of fasting largely depend on the food you eat after the fast.

As a general rule, the refeeding phase of a fast should last for half the duration of your fast.^[4] If you fasted ten days, for example, your refeeding period would be five days. (Two days of fasting would require one day of refeeding, and so on.) But what about intermittent fasters who go without food for only 12-24 hours?

The consensus is that intermittent fasters don’t have to worry about a refeeding phase. This is because the body doesn’t experience the same profound physiological changes that occur in prolonged fasts of 48 hours and longer. 

But no matter how long your fast for, you should always ‘break-fast’ with the right foods.

What foods should you break your fast with?

Until you’ve had a day or two of smaller, easy-to-digest meals, the following foods should be avoided after a prolonged fast:

• raw vegetables (including salad)
• nuts and nut butters
• dairy
• high-carb foods
• alcohol
• and junk foods like chips and cookies, etc.

These foods are inherently difficult to break down and digest, and may aggravate an already-weakened gut lining. And the same holds true for those who are just breaking an intermittent fast. But intermittent fasters typically don’t have to worry about excluding these foods for any meal other than the one they break their fast with.

Start with bone broth

One of the best foods to break a fast with is bone broth, which is high in amino acids (such as glutamine, glycine, and proline) that restore the gut lining.^[5] Try heating a cup or two with some added sea salt.

After thirty minutes to an hour of sipping your bone broth, feel free to eat a smaller-than-normal meal. Your digestive enzymes and stomach acid are revved up a bit from the bone broth at this point. Just make sure to avoid the foods in the list above, and to focus on higher proportions of fat and protein, and lower quantities of carbohydrates.

Focus on healthy plant-based fats such as avocados or coconut oil, and limited amounts of proteins from nuts and beans or fish and chicken.

The reason behind this is that your body’s insulin levels and blood glucose drop during a fast, which leads to many of fasting’s weight-loss and longevity benefits.^[6] So, the last thing you want to do is to shock your system with significantly elevated insulin and blood glucose levels: this can cause extreme tiredness, nausea, and increased fat storage.^[7]

Overeating (and eating too much of the wrong foods) after a prolonged fast or chronic calorie restriction is also known to cause a potentially fatal condition known as refeeding syndrome, which we’ll talk about later.^[8]

An ideal meal to break your fast would include some of the following: 

• Sautéed leafy greens such as spinach (generously patted with butter or olive oil)
• A 3-5 oz portion of wild-caught fish or chicken
• A small serving of wild rice or brown rice
• and a serving of cooked, low-glycemic veggies such as spaghetti squash or zucchini – with a splash of olive or avocado oil, of course

Generally, the longer you fast, the smaller you’ll want your first meal to be when breaking a fast. This can entail eating no more than a few bites of fruit after an extremely prolonged fast (21 days and longer), but most of our readers won’t have to worry about that. And again, you’ll want to maintain this lighter eating style for half as many days as your fast was.

In the days after you’ve broken your fast, you’ll want to incorporate fresh salads, pasture-raised meats, fruits and vegetables, smoothies, organic yogurt, whole grains, fish, and nut butters. Listen to your body, and if some foods make you feel bad, make a note of it, then switch back to foods that you know you can handle.

Finally, it’s essential that you eat enough food during your refeeding period.

Research shows that the organs in your body shrink during a fast and then enlarge after the refeeding period.^[9] This shrinking is theorized to occur in part due to the cellular cleansing (called autophagy) that happens in your fast – especially after Day 2 of a prolonged fast. Once the dead and damaged intracellular components are cleared out, the body ramps up its stem cell production, and the organs enlarge as part of the rejuvenation process.

But not eating enough quality food during this time could lead to less of the rejuvenating effect. If you’re experiencing unusual fatigue or headaches post-fast, try increasing your food and electrolyte intake.

What symptoms should you anticipate after a fast?

Rebound weight gain

One of the most exciting parts of a fast is looking at the scale to see how much weight you’ve lost. (In rare cases this can be upwards of four pounds for just a single day!) But over the next several days, you’ll almost certainly notice that a couple of those pounds creep back onto the scale…Does this mean your fast failed?

Absolutely not!

Much of the weight you lose in the first couple days of a fast is water weight. The body flushes out water to maintain electrolyte levels during your fast, and you’re also losing 20-30% of your regular water intake from the food you’re not eating. So when you start eating again, you gain most of that water weight back.^[10]

This can seem like a slap in the face from the fasting gods, but it’s totally normal. You still lost between 1-2 pounds of fat per day. And if you stick with healthy eating habits and get daily exercise, you’ll keep more of it off!

Bottom line: don’t obsess over the scale when you break your fast—trust in the process of fasting and the science behind its amazing weight-loss effects.

Diarrhea, constipation, and other stomach problems

It’s hard to believe that eating nothing could cause diarrhea or other gastrointestinal issues. But if this happens to you, don’t be surprised. Fasting is known to cause significant shifts in the intestinal microbiome.^[11] So if you have a severely imbalanced gut, you’re likely to experience some GI upheaval as you come back into a balanced state of intestinal flora.

Some amount of gastric distress is expected once you’ve broken your fast, also. Your system might be too sensitive for certain foods, or to the amount you’ve eaten, which can cause diarrhea, constipation, and other symptoms in the days after you’ve reintroduced food. Another reason to break your fast slowly and cautiously!

If you become dehydrated or experience dizziness or fever along with your GI symptoms, consult your doctor right away.

Fatigue

Even though your stomach is resting during a fast, your body is working at a frenzied pace to make you healthy, fit, and youthful.[12] (Yes, fasting may indeed reduce biomarkers for aging.) So a large part of the fatigue you experience during and after a fast may be due to the energy that’s being used for processes like cellular autophagy and rejuvenation.

So if you’re feeling less than 100% of your natural energy in the refeeding period, don’t push yourself. Keep your exercise to a minimum – avoiding all intense workouts such as heavy weightlifting – and schedule more breaks (even naps!) than you’re used to taking. Your body will thank you in the days after!

In Conclusion: thoughts on how to break your fast

Even though there is still work involved in this final fasting phase, the results will be worth it.

After you finish your fast, your cells may be rejuvenated, your mental capabilities and energy may be higher, and your waistline will be slimmer! And if you break your fast with the right meal, and you choose the right foods for a long enough refeeding period, you’ll maximize your results! Just be prepared for a few possibilities (including regaining some of the weight, and possibly fatigue) in your post-fasting life.  

As always, please consult your physician before you undertake any fast longer than a day, or if you plan on making any changes to your daily eating habits. And if you experience unusual or severe symptoms during your refeeding phase, consult with a doctor immediately or visit an emergency room.