Warrior Diet: Everything You Need to Know Before Starting

Meta description: Wondering how the Warrior Diet could help you to lose weight? Check out our guide to starting this fasting diet to find out all you need to know.

This article covers how to get started on the Warrior Diet, its health benefits, and some tips for success.

There is a whole plethora of intermittent fasting types to follow. The warrior diet can be considered an intermediate-level fasting type due to how long you have to fast on a given day.

Although the most popular method of this diet is to have an eating window in the evening, it is a flexible intermittent fasting style that can be adjusted to your own needs.

The Warrior Diet, or 20:4 diet, comes with many health benefits, including helping you to lose weight by reducing calorie intake, supporting blood sugar control, and reducing body fat.

  • What is the Warrior Diet?
  • How to do the Warrior Diet
  • What are the benefits of following a Warrior Diet?
  • What to eat and avoid during the Warrior Diet?
  • What are the downsides when following the Warrior Diet?

What Is a Warrior Diet?

The Warrior Diet or the 20:4 diet is a style of intermittent fasting that requires you to fast for 20 hours and then feast for 4 hours.

This type of fasting is aptly named the warrior diet because it’s based on warriors in history who would eat very little during the day and then feast in the evening, and it was first introduced as a concept to aid weight loss back in 2001.

There are different ways of following this plan but the most popular is to follow the 20:4 eating pattern, fasting for 20 hours, and eating for the remaining 4 hours.

This diet is thought to help people with weight loss but must be followed carefully to avoid overeating during the eating period, leading to weight gain.

How to Start the Warrior diet?

The 20:4 diet is a popular intermittent fasting style and there are a few ways to follow the Warrior Diet for the best results. We have summarized a few of them below.

If you’re just starting out with intermittent fasting, however, it might be best to start with a more beginner-friendly plan, such as the 16:8 method.

  1. Ease into a new fasting pattern 

When it comes to intermittent fasting, there is a tonne of different styles to try out but it is recommended that you begin with less challenging options.

You may begin intermittent fasting with the 12:12 diet or the 14:10 fast to allow your body to get used to the fast and build up a resistance to any of the side effects of intermittent fasting.

Jumping straight into the 20:4 diet may mean having to deal with some negative side effects and it is more likely you will have a negative experience.

Begin with less challenging fasts and build up to this kind of diet.

  1. Eat meals that are high in protein

During the eating window of the 20:4 diet, it is important that you eat lots of high-protein meals. Protein is essential for the body and can make you feel more energized.

Eating protein during this window will ensure that, during the fasting period, your body doesn’t burn muscle mass for energy and instead burns fat.

Eating high-protein meals can ensure that your body keeps burning fat as fuel to help reduce body weight and encourage the building of muscle mass when coupled with strength training.

  1. Control your hunger pangs by using appetite suppressants

A 20-hour fasting period is a long time to go without food, which means you will likely get hunger pangs and cravings during this time.

Appetite suppressants, such as our DoFasting Appetite Suppressant, to help you to overcome these feelings.

An appetite suppressant can help to keep hunger at bay and fills your stomach with fiber. This signals to the brain that it is time to stop eating, helping to eliminate cravings.

Additionally, appetite suppressants tend to have added nutrition to help your body function during fasting periods.

  1. Keep blood sugar levels balanced by consuming small portions of foods 

During the fasting period, there might be some issues with low blood sugar. Due to not eating for a long while, you could start to feel tired and dizzy. You can reduce these side effects by eating small portions of food.

You can consume small portions of things like hard-boiled eggs and cottage cheese to get you through the tough fasting period, however, eating even small portions of food will break most prolonged fasting benefits such as autophagy.

You should only resort to this if you’re feeling too uncomfortable with the side effects of fasting for an extended period of time.

  1. To fully improve the body’s ability to use fat for energy, follow the Warrior diet for 3 weeks

When it comes to what to eat when on this diet, there are three phases you can follow to ensure you get the most out of the diet and ensure you get all the nutrition you need.

Week 1 aim is to detox the body 

During phase one of the Warrior Diet meal plan, you should fast during the 20-hour fasting window. You should only consume unprocessed foods including vegetable juices, clear broth, cottage cheese, hard-boiled eggs, and raw vegetables and fruit.

When it comes time to eat, start out with a salad and dressing (the dressing should be oil, and vinegar-based), then follow it up with lots of plant proteins, wheat-free grains, and some cooked vegetables.

During this phase, you may eat grains and starches.

Phase 2 (week 2) aim is adapting to use fat as energy

During phase two, you should follow the same pattern of undereating, with clear broth, raw fruits, and vegetables, etc., and begin your eating period with the same kind of salad as before.

You should then consume lots of lean animal proteins, cooked veg, and at least one handful of nuts. You may not eat any grains or starches during this phase.

Phase 3 (week 3) aim is adapting to use carbs as energy

For phase three, you would cycle between high carbs and high protein meals. This means 1 - 2 days of high carbs and then 1 - 2 days of high protein and low carbs.

For the high carb days, you should undereat as normal, eating raw fruits and vegetables, hard-boiled eggs, etc., and begin your eating period with the same salad as on week one. 

You should then consume only small amounts of animal protein and one main carbohydrate food, like corn, potatoes, or pasta accompanied by cooked veg.

For the high protein and low carb days, undereat as normal and begin with the same salad, then eat between 8 - 16 ounces of animal protein with cooked, non-starchy veg.

You cannot eat grains or starches during the high protein period but you may consume tropical fruit as a dessert.

It is recommended that once you have completed this cycle, you go back to the beginning and start again, though some people choose to stay in phase three.

You should also accompany this eating pattern with multivitamins and exercise.

What Are the Benefits of Following the Warrior Diet?

This diet is so popular because of its many health and weight benefits. Compared to more beginner-friendly IF plans, the warrior diet can provide more noticeable results, and much faster.

Weight loss

The popularity of the diet comes from its incredible ability to help you lose weight in a healthy way. There are a few ways it aids people in losing weight.

To begin with, the 20:4 fast imposes a calorie restriction which is one of the best ways to promote weight loss.

The 4-hour eating window is a short space of time to consume food, meaning that overeating is unlikely. This means you’re more likely to be eating at a calorie deficit as you restrict your eating time to just four hours in the day.

Indeed, though binge eating is a possible negative of this diet, most people find that eating nutrient-dense foods in the four-hour eating window can encourage weight loss.

It is imperative that you eat as much natural, non-processed food in the 4-hour period as possible.

Another way that the 20:4 diet may help people with weight maintenance is that it can help to boost metabolism. It is thought that intermittent fasting can boost metabolism by at least 14%.

Fasting also may induce a metabolic switch in the body that forces it to utilize fat instead of blood sugar as fuel. This state is called ketosis.

Improves cognitive health

Some research suggests that intermittent fasting may help to boost cognitive health. The Warrior Diet is thought to be a good way to boost brain function.

The main way this diet is thought to boost brain health is by regulating inflammatory pathways in the brain.

There is also some evidence to suggest that intermittent fasting could protect against neurodegenerative diseases like Alzheimer's disease.

Though the research is promising, more studies may be needed on this subject.

Reduced inflammation in the body

Inflammation from oxidative stress is thought to wreak havoc on the body. It has been linked to a number of chronic conditions, including diabetes and heart disease.

Intermittent fasting has been shown to reduce inflammation in the body and help to protect against these kinds of diseases.

Reduces the risk of getting diabetes

The Warrior Diet is thought to improve blood sugar control which could help those with type 2 diabetes.

It is also thought that more blood sugar control can help to reduce insulin resistance, which can protect against the development of type 2 diabetes.

Though considered a good method of controlling blood sugar, there is a risk of hypoglycemia during fasting phases.

Improved energy levels

Along with improved brian function comes improved productivity. It is thought that the improvement in cognitive ability can boost productivity in users of intermittent fasting.

Additionally, fasting has been shown to increase physical energy levels, helping people to feel more energized when using fasting methods.

Improved cardiovascular health

All kinds of intermittent fasting are thought to be good for heart health and this includes the Warrior Diet.

Fasting reduces risk factors of poor heart health and cardiovascular disease. These markers are usually high cholesterol, high blood pressure, and increased triglyceride numbers.

Fasting is thought to reduce LDL cholesterol levels, which are known as the bad kind of cholesterol, as well as reduce blood pressure and lower triglyceride numbers.

Fasting may help to protect against the development of cardiovascular disease. It also helps with weight loss which can improve heart health too.

Can help to build muscle mass

The Warrior Diet promotes increased fat burning which can help to build muscle mass. As more fat is burned, less protein is used as fuel and more muscle can be built.

It may be slow to build muscle on the Warrior Diet but your weight will not fluctuate as much as when using other diets.

It is essential to incorporate exercise into your daily schedule but it should be scheduled during your food intake window so you don’t become exhausted too easily.

What to Eat and Avoid During the Warrior Diet? 

When it comes to what you should and shouldn't eat on the Warrior Diet, there are differences between the two eating periods. During the fast, you should eat:

  • Raw fruits, like apples, bananas, kiwi, and mango
  • Vegetable juice, like beet and carrot juice
  • Broth, both chicken and beef
  • Raw vegs, such as peppers, carrots, mushrooms, and greens
  • Olive oil and apple cider vinegar
  • Dairy, including yogurt and cottage cheese
  • Protein, from hard-boiled eggs
  • Zero-calorie beverages like coffee, tea, and water

During the four-hour window for eating, you should consume:

  • Cooked vegetables, like cauliflower, sprouts, zucchini, greens
  • Protein, from chicken, steak, fish, turkey, eggs
  • Starches, like beans, potatoes, corn, sweet potato
  • Grains, including oats, quinoa, pasta, bread
  • Dairy, like milk, cheese, and yogurt
  • Fats, from oils and nuts

And along with foods that you should eat, come some foods you should definitely not eat on the Warrior Diet. These include:

  • Confectionary
  • Cookies and cakes
  • Chips
  • Fast food
  • Fried food
  • Processed meats
  • Refined carbs
  • Artificial sweeteners
  • Sugary drinks

These processed foods can become addictive and will lead to withdrawal symptoms, like headaches, during the fast. 

Processed foods also offer very little nutritional value and should be considered wasted calories during the 4-hour eating period.

What Are the Downsides When Following the Warrior Diet?

As with any weight-loss method or diet, there are some downfalls of the Warrior Diet. We’ve summarized them briefly below for you to be aware of before embarking on this kind of fasting diet.

It may not be suitable for everyone

There are a few groups of people whom the Warrior Diet is definitely not suitable for. These include:

  • Those who are pregnant or breastfeeding - With long fasting periods and restricted eating patterns, there is some chance of malnutrition. This is heightened when pregnant or breastfeeding as you are sharing your resources with another.
  • Children and teens - Anyone under the age of 18 should not try the Warrior Diet as their bodies are still growing and they have high metabolisms.
  • Anyone with a condition that could be exacerbated by fasting - If you have any of these conditions seek medical advice before starting a fasting diet.

Sticking to the whole 20 hours without food may be too difficult

20 hours is a very long time without food. Some people may not be able to last this long without eating which could lead to binge eating.

You may also find that you cannot engage in activities you normally would, like socializing, which can make this diet even harder.

Indeed, these long fasts and surviving on effectively one meal a day can have some side effects that make it even more difficult.

Fasters who choose the Warrior diet may experience side effects

Side effects of the Warrior Diet’s long fasts with only one meal include:

  • Dizziness
  • Fatigue
  • Low energy
  • Extreme hunger
  • Anxiety
  • Insomnia
  • Constipation
  • Fainting
  • Irritability
  • Hormonal imbalance


The Warrior Diet is a style of intermittent fasting that involves fasting for 20 hours a day and then feasting for 4 hours. It is based on the historical warrior's diet, wherein they would eat little during the day and feast in the evening.

The diet comes with many health benefits, including improved cognitive health, improved heart health, reduced inflammation, and weight loss.

Though there are some downsides, the Warrior Diet has been shown to help people with weight loss and to boost overall health too.


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