What Is the Warrior Diet?

The warrior diet is a type of intermittent fasting protocol that involves extended periods of fasting and short periods of feasting.

The feasting portion of the warrior diet is quite literal — dieters are encouraged to eat 85% to 90% of their calories during this window, which can be up to 1,800 calories in one sitting for someone on a typical 2,000 calorie plan or up to 2,700 calories in one sitting for an active person who needs 3,000 calories per day.

What Experts Say

“The warrior diet is a stricter type of intermittent fasting, alternating between 20 hours of undereating and 4 hours of unlimited intake. Experts worry this diet may lead to nutrient deficiencies and warn that it is inappropriate for many groups (like athletes or pregnant women).”
Chrissy Carroll, RD, MPH


Fasting is nothing new, and the practice of fasting has a diverse, complex history. Perhaps the earliest records of fasting go back to ancient Greece when philosopher Pythagoras touted the virtues of fasting. Hippocrates and other prominent healers, like the Renaissance doctor Paracelsus, were also advocates of fasting.

Fasting has been a critical component of nearly all the world’s major religions — Judaism recognizes multiple fasting days throughout the year; Muslims fast during the holy month of Ramadan, and Christians observe a 40-day fast during Lent.

Fasting has also been used as a means for political protest, as evidenced by the Suffragette hunger strikes and Mahatma Gandhi's fasting episodes during the struggle for Indian independence. 

Now, fasting is a popular weight-loss or performance-enhancement protocol in the wellness world. Intermittent fasting, in particular, has skyrocketed in popularity because preliminary results from weight loss studies are positive.

The warrior diet is a type of intermittent fasting developed by Ori Hofmekler, a renowned author in the world of health and fitness. Hofmekler created the diet in 2001 after years of observing himself and his colleagues in the Israeli Special Forces.

It’s important to note that the warrior diet isn’t based on science in the clinical sense — instead, the warrior diet is based on Hofmekler’s own observations and opinions on the tactics he used to stay fit during his time in the military.

How It Works

The warrior diet involves fasting for 20 hours overnight and during the day, and then overeating during a four-hour window in the evening. This principle is based on the idea that our primitive ancestors spent their days hunting and gathering and would feast at night.

What To Eat

Technically, there aren’t any off-limits foods on the warrior diet. It’s encouraged that you consume nutrient-dense foods and get in plenty of fruits, vegetables, and protein, but you could just as easily reach for a pizza during your four-hour eating window.

Hofmekler suggests that your meals should be based on healthy fats and large portions of protein, specifically dairy protein sources such as cheese and yogurt. There’s no need to count calories on the warrior diet if you follow Hofmekler’s suggestions and focus on unprocessed foods.

Compliant Foods

Fruit and Vegetables: Try to consume a few servings of fruits and vegetables each day in order to ensure you get enough essential vitamins and minerals.

Grains: Whole-grain foods, such as sprouted wheat bread, quinoa, rice, bulgur and oatmeal are all great options to fuel up on during your eating window.

Dairy: The warrior diet particularly encourages dairy foods, especially raw and full-fat ones. Hofmekler is a fan of cheese, yogurt, and raw milk.

Protein: People on the warrior diet are urged to consume large amounts of protein. Protein is essential for maintaining and building muscle mass, a key goal outcome of the warrior diet.

Beverages: On the warrior diet, you can consume any zero-calorie beverages during your fasting window, and essentially anything you want during your feeding window. The diet recommends water, black coffee, and milk.

Non-compliant Foods

Again, there aren’t any foods that are totally off-limits for the warrior diet, but there are some foods you should try to keep to a minimum on any diet:

Sugary Processed Foods: Packaged sugary foods are one of the main culprits behind many chronic diseases, including diabetes and inflammatory bowel disorders. Try to keep added sugar to a minimum.

Salty Processed Foods: Even though they might seem healthier than sugary foods, salty snacks can be just as damaging to your blood sugar and other health markers. If you’re looking for something crunchy and savory, try veggies with hummus or guacamole. You can also make your own savory snacks at home.

Sugary Beverages: Try to keep your intake of soda, energy drinks, and juice with added sugars low. Sugary beverages are a leading cause of weight gain, tooth decay, and illness.

Recommended Timing

Timing is the key component of the warrior diet. The entire protocol is based around the idea that long periods of fasting and short windows of overeating lead to optimal health, fitness, and body composition.

During the 20-hour fasting period, you should consume only minimal calories. Hofmekler encourages dieters to sustain themselves on small portions of dairy, hard-boiled eggs, and raw produce. You can also drink zero-calorie beverages, including coffee, during the fasting period.

When it’s time for your feeding window, you can essentially eat however much of whatever you want until the four hours are over. You can determine your feeding window based on a timeframe that works well for you, but most people save their feast for the evening hours.

When it’s time for your feeding window, you can essentially eat however much of whatever you want until the four hours are over. You can determine your feeding window based on a timeframe that works well for you, but most people save their feast for the evening hours.

Resources and Tips

The best resource for the warrior diet is Hofmekler’s book on the subject. The Warrior Diet: Switch on Your Biological Powerhouse for High Energy, Explosive Strength and a Leaner, Harder Body covers all the bases of the warrior diet and provides details on how to get started and maintain the diet for the long-term.

There’s plenty of research on the health benefits of intermittent fasting in general, but there is very little evidence on the exact methods of the warrior diet. Keep this in mind when deciding whether or not to try the diet.


There aren’t any modifications to the warrior diet itself. If you deviate off of the 20:4 protocol, you wouldn’t be on the warrior diet anymore. However, there are many other intermittent fasting protocols that may be more beneficial and have more research behind them. 

Those include the 16:8 method, the 5:2 diet, Eat-Stop-Eat, and alternate-day fasting. See the Similar Diets section for more intermittent fasting protocols.

Pros and Cons

  • May aid weight loss

  • May improve blood sugar

  • May help with inflammation

  • May reduce risk of cognitive disease

  • Difficult to follow

  • May lead to binge eating

  • Inappropriate for many groups

  • Many potential side effects

  • Nutrient deficiencies

  • Lacks evidence


May Aid Weight Loss: Preliminary and short-term evidence links intermittent fasting to weight loss, including 20-hour cycles. Consistent alternate-day fasting has also been shown to help overweight people lose a substantial amount of body fat and decrease the risk of cardiovascular disease. Long-term studies in large diverse groups are needed to better understand the link between intermittent fasting and weight loss.

May Improve Blood Sugar: Fasting, in general, is strongly associated with improvements in blood sugar control and insulin sensitivity. This potential benefit can be lost, however, if you choose to eat high-carbohydrate or sugary foods during your feeding window. Also, there is not evidence directly linking 20:4 fasting to these benefits.

May Help With Inflammation: Inflammation is a leading cause of disease, including heart disease, diabetes, some cancers, bowel disorders and more. Research suggests that some types of intermittent fasting could be a good way to combat chronic inflammation. But again, there is not evidence directly linking the Warrior Diet or 20:4 fasting to these benefits.

May Reduce Risk of Cognitive Disease: Animal studies have found that intermittent fasting may have a protective effect against cognitive decline and diseases such as Alzheimer’s disease. The research in this area is fledgling, however, and more studies are needed to confirm this effect. Also the research was not conducting using the Warrior diet.


Difficult to Follow: While our paleolithic ancestors may have easily gone 20 hours without food, that’s not a norm in modern society and we aren’t conditioned to follow that pattern. Fasting for 20 hours every day is very difficult, and you may experience severe cravings, hunger and other symptoms. Severe cravings and high hunger cues could lead to overeating.

May Lead to Binge Eating: Although reduced calorie intake is common in many fasting protocols, it’s possible that you could consume too many calories during your four-hour on the warrior diet window due to cravings or feelings of deprivation. You may also experience obsessive thoughts about food during the fasting period.

Inappropriate for Many Groups: Many people should not follow the warrior diet, including women who are pregnant or nursing. People who have diabetes, and people who require food with his or her medications should also avoid this diet.

Many Potential Side Effects: Depriving your body of substantial calories can lead to fatigue, brain fog or difficulty focusing, “hanger”, mood swings, stress, anxiety, dizziness or lightheadedness, hormonal disruptions and more.

Nutrient Deficiencies: Because your eating is restricted to so few hours, it may be difficult to consume the recommended servings of fruits and vegetables, especially when you may be focused on more carb-heavy or protein-dense foods. Most research about intermittent fasting focusses on Ramadan, alternative days of caloric restriction, 16:8 protocol, and 5:2 protocol. 

Lacks evidence: There isn't strong evidence-based scientific studies legitimatizing the "Warrior diet" beyond the extrapolated concept of Intermittent fasting. More evidence is needed about this particular variation to know if it is effective and to understand any potential side effects or drawbacks.

How It Compares

USDA Recommendations

The federal dietary recommendations include five food groups: fruit, vegetables, grains, dairy, and protein. The key recommendations in the federal guidelines include:

  • A variety of vegetables from all of the subgroups—dark green, red and orange, legumes (beans and peas), starchy, and other
  • Fruits, especially whole fruits
  • Grains, at least half of which are whole grains
  • Fat-free or low-fat dairy, including milk, yogurt, cheese, and/or fortified soy beverages
  • A variety of protein foods, including seafood, lean meats and poultry, eggs, legumes (beans and peas), and nuts, seeds, and soy products
  • Oils
  • Limited saturated fats, trans fats, added sugars and sodium”

The warrior diet encourages dieters to eat raw fruits and vegetables, dairy, whole grains and protein, so on the surface, it seems this diet is consistent with the federal recommendation. However, dieters are really free to choose whatever foods they want, so there’s no guarantee that you will consume enough nutrients on the warrior diet. Additionally, it’s hard to consume the recommended amount of nutrient-dense foods in just four hours.


It’s important to know how many calories you should be consuming each day in order to reach your weight goals, whether your goal is to lose, maintain, or gain weight. Our Weight Loss Calorie Goal Calculator can help you determine your daily caloric needs.

Most people need around 2,000 calories per day. Smaller-framed women and children may need less; men and very active people may need more. Note that calorie needs are extremely individual: Age, height, weight and activity level all play a role in your caloric needs.

The warrior diet doesn’t specify calorie intake. In fact, Hofmekler discourages calorie counting and instead encourages dieters to simply focus on maintaining the 20:4 fasting ratio.

Similar Diets

The 16:8 Protocol: This is one of the most popular intermittent fasting methods. Followers of this method eat all of their calories for the day in an 8-hour window and fast for the remaining 16 hours of the day. The 16:8 method is popular for beginners because you should be asleep for about half of your 16 fasting hours.

The 5:2 Protocol: This method involves eating how you normally would on five days of the week, and eating only 500-600 calories on the other two days. This is another popular fasting protocol, but the fasting may cause binge eating.

Eat-Stop-Eat: Eat-Stop-Eat is an aptly named method that involves a complete 24-hour fast once or twice a week. For example, if you stop eating at 8 p.m. on Saturday night, you wouldn't eat again until 8 p.m. on Sunday night.

Alternate-day Fasting: When following this protocol, you would eat in an ongoing cycle: Fast one day, eat normally the next, and so on. Usually, fasting days on this protocol allow for 500-600 calories.

A Word From Verywell

Intermittent fasting can be an effective way to reach your health goals if done properly, but so can any other diet that encourages whole, nutritious foods. The key is choosing a diet that works for you for the long-term.

If you want to try intermittent fasting, the warrior diet is probably not the best place to start. Instead, try out more evidence-based methods the 16:8 protocol or 5:2 method. The warrior diet is tough to stick to especially for beginners and it lacks scientific evidence.

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