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Intermittent Fasting Foods to Eat and Limit


Figuring out what to eat during your eating window can be tricky when you’re fasting. After all, intermittent fasting focuses on when instead of what you eat. However, fasting foods can also impact your results — like weight loss and blood sugar control — and not just the abstinence from eating.

In this article, you’ll learn the best foods for intermittent fasting, including various types of meat, seafood, and fresh produce. It’s always a good idea to pair your fasting protocol with a healthy diet.

What is Fasting?

Fasting is the practice of avoiding any food or drink containing calories for a specified period, which can range from 12 hours to 36 hours or more (*). There are two categories that fall under the broad term “fasting” — intermittent fasting and prolonged fasting.

Intermittent fasting (IF) is more tolerable because you can simply skip a meal or fast up to 36 hours, which is more advanced. On the other hand, prolonged fasting lasts anywhere from 48 hours or even longer.

Your body goes through a series of changes during fasting, starting with the depletion of your stored glycogen and fat. A metabolic switch happens in which you now rely on ketones for energy instead of glucose (*).

Research shows that this has several benefits, including fat loss, increasing the effectiveness of cancer treatment, reducing inflammation, and other anti-aging benefits (* , *, *).

When combined with a low-carb or keto diet and an exercise regimen, fasting leads to greater benefits and may even help you attain metabolic flexibility, which boosts health and performance.

Can You Eat While Fasting?

Except for fat fasting, which is a type of intermittent fasting in which you eat only high-fat foods to reach ketosis — the answer is no — foods are not allowed during a fast. Anything that contains calories, including drinks with cream and sugar, will technically break your fast.

Drinks with zero calories, on the other hand, are allowed during a fast. Water and calorie-free electrolyte drinks (such as Perfect Keto Electrolytes) are encouraged to prevent dehydration. Drinking black coffee or tea is also acceptable and these may keep you alert and focused, although note that caffeine is a diuretic, which can increase fluid loss.

Foods to Eat While Fasting

What can you eat when fasting? For the next sections, we’re going to explore different foods for fasting that are good for you. They’re easy to digest and low on the glycemic index (GI). These low-GI foods won’t spike your blood sugar when you have them during your eating window.

Meat, Eggs, and Poultry

Animal-based foods are excellent sources of protein, which has very little effect on your blood sugar levels. Egg yolks and fatty cuts of meat (like pork belly and chicken thighs) provide healthy fats that enhance nutrient absorption.

  • Beef
  • Pork
  • Chicken
  • Turkey
  • Lamb
  • Goat
  • Pheasant
  • Bison
  • Venison
  • Eggs (chicken, duck, turkey, goose, quail)

Fish and Seafood

Fish and seafood are also great because they provide protein with essential amino acids to prevent muscle loss, absorb nutrients, and produce hormones. They serve as sources of omega-3 fatty acids as well, which protect you from various diseases.

  • Salmon
  • Tilapia
  • Mackerel
  • Fish eggs
  • Herring
  • Shrimp
  • Crab
  • Lobster
  • Mussels
  • Oysters

Fruits and Vegetables

Certain fruits and veggies are better options for breaking a fast because they’re low in carbohydrates and fiber. Eating too much fiber right after fasting may cause gas, bloating, and cramping. We would recommend these, and make sure that vegetables are peeled and cooked:

  • Watermelon
  • Cantaloupe
  • Asparagus
  • String beans
  • Cucumbers (without seeds)
  • Mushrooms
  • Baby spinach
  • Zucchini


Having something to drink can curb hunger. Some are even known to suppress appetite naturally. Aside from plain water, you may want to try these drinks:

  • Coffee
  • Sparkling water
  • Lemon-infused water (slices of lemon in a pitcher of water)
  • Tea (black tea, green tea, oolong tea) without sweetener
  • Black coffee without sweetener or cream
  • Calorie-free electrolytes


Doing frequent fasts without fueling with nutrient-dense foods when you break these fasts will increase your risk of nutrient deficiencies. Taking supplements will help on your fasting days. Make sure they don’t contain added sugars.

These supplements are generally okay for fasting. You can also take them right before starting a fast:

  • Coffee
  • Multivitamins
  • Creatine (in capsule form, usually for pre-workout)
  • Probiotics
  • Water-soluble vitamins (vitamin C and B complex)
foods to eat while fasting

Foods to Limit During a Fast

Intermittent fasting will boost your health and give your digestive system a break, but it should not be used as an excuse to binge on refined carbohydrates and highly processed foods when you’re done fasting.

Avoid the following:

  • White bread and bagels
  • White rice
  • Pasta
  • Breakfast cereals
  • Desserts, such as cakes, cookies, and ice cream
  • Processed meats
  • Soda
  • Fruit juices, smoothies, and shakes high in sugar

These foods do not provide long-lasting energy by causing swings in your blood sugar levels. Additionally, they negatively impact your health by triggering an inflammatory response (*). Break your fast with options that are good for you.


Here are common questions and answers on the topic of fasting foods.

How do I manage my hunger during a fast?

There are many ways to help yourself not feel hungry while fasting, such as staying hydrated with water and zero-calorie electrolytes.

Try other distraction methods as well. Immerse yourself in a challenging task or activity, such as learning a new skill. Also, keeping food out of sight will help you to stop thinking about food.

Can I eat snacks on a fast?

Since snacks contain calories, they will technically break your fast. So the answer is no — you cannot eat snacks while fasting.

However, if you end the fast during snack time (for example, at 3 pm), excellent snack options include eggs, bone broth, and a low-carb protein shake (e.g. whey protein isolate).

Can I workout during a fast?

Absolutely. It’s fine to continue your workouts even without food. However, it may be a good idea to modify them by reducing their intensity and duration, especially since fasting can make you feel hungry and sluggish — if you’re not used to it yet.

For example, instead of running, try brisk walking. Or instead of lifting weights, switch to a low-impact bodyweight workout. Read our separate guide on combining intermittent fasting and exercise.

The Bottom Line

A successful fast also entails being mindful of the foods you consume when you break that fast, a.k.a. your feeding window. The best foods to break intermittent fasting are low in carbohydrates and provide substantial amounts of protein and fat.

Eggs, animal foods, and non-starchy vegetables and fruits won’t just prevent blood sugar spikes, but also nourish your body with lots of vitamins and minerals, and support weight loss. Keep your meals healthy during your feeding window.

Remember to avoid sugary and high-carb foods. White bread, white rice, cookies, candies, cereals, fruit juices, soda, and french fries will only leave you feeling sluggish. Plus, they might trigger binge eating and unhealthy cravings for the rest of the day.

Regardless of your fasting plan, following these guidelines will help you stay on track.

6 References

Longo V et al. Fasting: Molecular Mechanisms and Clinical Applications. 2014 January 16

de Cabo R et al. Effects of Intermittent Fasting on Health, Aging, and Disease. 2019 December 26

Dowis K et al. The Potential Health Benefits of the Ketogenic Diet: A Narrative Review. 2021 May 13

Tiwari S et al. Effect of fasting on cancer: A narrative review of scientific evidence. 2022 August 10

Zhou R et al. The influence of fasting and caloric restriction on inflammation levels in humans. 2021 April 16

Cleveland Clinic. 5 Foods That Can Cause Inflammation. 2020 June 15

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