Warrior Diet (20/4 Fasting): What You Need To Know

The What Diet?? Yea, you read it right, The Warrior Diet. Also called 20/4 fasting.

This diet trend has us going back to our early roots as ancient warriors and hunter-gatherers.

Just as our primitive cousins would hunt or battle all day, and eat their large meals at night, this diet has you fasting all day, and eating all of your calories in the evening.

This article discusses everything you need to know to determine if the Warrior Diet is right for you if you’re looking for a safe way to lose weight and improve your health, all while awakening your inner She-Ra.

What is the warrior diet and how can it help me lose weight?

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What Is the Warrior Diet

The warrior diet requires you to spent 20 hours a day fasting (called “undereating” in warrior lingo), and only four hours eating (called “overeating”).

Thus, the alternative name: 20/4 fasting.

During the “undereating” period, you are encouraged to drink lots of fluids along with very small snacks, like raw fruits and veggies, dairy and hard boiled eggs.

At night you eat one huge meal. And you can eat as much as you want at that meal…

As long as you’re eating from an approved list of foods and staying away from processed foods, sugars and sweeteners.

This diet is considered a form of intermittent fasting or time-restricted eating, which are umbrella terms for a method of eating where you fast and eat during defined periods.

This 20/4 fasting method has you fasting for 20 hours and eating for 4 hours.

Followers of this diet claim that this method burns fat, boosts energy levels, improves brain function and helps with cell repair – all things that intermittent fasting has been proven to do.

How the Warrior Diet Began

The Warrior diet is based on a book written by Ori Hofmekler, a former member of the Israeli Special Forces.

He was inspired by his time in the army and by the eating styles of the ancient warrior societies of Rome and Sparta.

What sets the warrior diet apart from other kinds of intermittent fasting is the fact that it is NOT based on science.

This diet is based on observation and opinion. Hofmekler believed that humans naturally evolved to eat in a warrior diet style back when humans were hunter-gatherers.

Benefits of the Warrior Diet

I want to reiterate the fact that this diet is NOT based on science.

That said, some experts believe that the warrior diet shares some intermittent fasting benefits because it is a variation of intermittent fasting.

endomorph weight loss

Weight Loss

Various methods of intermittent fasting, including a 20-hour fasting window, have been linked to weight loss.

In one study, normal weight adults who ate one meal per day showed a significant change in body composition which included a reduced fat mass and greater muscle mass.

Improved Blood Sugar Control

A study of people with type 2 diabetes who fasted for 18-20 hours per day, showed post-meal blood sugar control along with a decrease in body weight.

Anyone with diabetes should consult with their doctor before trying any form of intermittent fasting because it may disrupt your blood sugar levels.

Other Benefits

Honestly, most people who are interested in the warrior diet are doing it to lose weight.

If you have genuine health concerns and are interested in health benefits like improved brain health and reduced inflammation, I recommend you look at the other intermittent fasting types.

The other types have a larger body of scientific evidence backing up the benefit claims.

Is the warrior diet too hardcore for me?

Disadvantages of 20/4 Fasting

For me, the biggest concern with this diet is that it has virtually no scientific support backing it up.

It may work for some people, but there isn’t enough research to say it will work for most people.

If you are considering the warrior diet, please make sure to discuss it with your health care professional before you begin.

Here are a few more disadvantages to this largely untested diet:

  • You might make bad food choices because you are SO hungry at the end of the day.
  • It probably will be difficult for most people to stick to since it limits eating to a 4-hour period each day.

A couple more things to think about:

  • It may be difficult to get all the nutrients you need in one daily meal.
  • Like other forms of intermittent fasting, it is not appropriate for children, women who are pregnant, nursing or trying to get pregnant, extreme athletes, people who are underweight, people with a history of eating disorders.

Getting Started With the Warrior Diet

The warrior diet is an extreme form of intermittent fasting and is very different from the typical three meals a day most people are used to.

If you decide that the warrior diet is something you want to try, ease into the diet gradually. Start out by skipping a meal once or twice a week.

When you have adjusted to that, try extending your undereating periods to the 20 hours required on the warrior diet.

Is the 5:2 diet the best kind of intermittent fasting for weight loss?

What To Eat on The Warrior Diet

When on the warrior diet, you should eat only whole, nutritious, organic foods. What you can eat depends on which phase you’re in.

Serving sizes are not specified and there is no set calorie target during this diet.

Foods to Eat During the Undereating Phase

During the undereating phase, eat only small portions of the following foods:

  • Protein: poached or hardboiled eggs
  • Dairy: milk, yogurt, cottage cheese
  • Broth: chicken or beef
  • Raw Vegetables: carrots, peppers, mushrooms, greens, onions
  • Fruits: bananas, apples, mango, kiwi, peach, pineapple
  • Vegetable Juice: beet, carrot, celery
  • Small amounts of olive oil, apple cider vinegar
  • Water, seltzer, coffee, tea

Foods to Eat During the Overeating Phase

  • Protein: chicken, turkey, steak, fish, eggs
  • Starches: potatoes, corn, sweet potatoes, beans
  • Grains: pasta, bread, barley, oats, quinoa
  • Dairy: milk, cheese, yogurt
  • Cooked Vegetables: zucchini, greens, cauliflower, brussels sprouts
  • Fats: olive oil, nuts
What can I eat during a fast?

What To Avoid on The Warrior Diet

When following the warrior diet, avoid all processed foods, preservatives, and foods with added sugars or sweeteners.

The following foods should be avoided.

  • Fast food
  • Fried food
  • Processed meats like bacon and lunch meat
  • Refined carbohydrates
  • Candy, cookies, cakes
  • Chips, crackers
  • Canned fruits
  • Artificial sweeteners
  • Sweet drinks like fruit juice and soda

How To Do The Warrior Diet

To get started, dieters follow a three-week plan divided into phases.

Hofmekler designed this three-week start to “improve the body’s ability to utilize fat for energy”.

Phase I – Week 1: “Detox”

  • For 20-hours each day (Undereating Period): Snack very lightly on broth, raw fruits and vegetables, hard-boiled eggs, vegetable juice and dairy.
  • For 4-hours each day (Overeating Period): Start with a salad with oil and vinegar dressing.
  • Then eat a large meal of plant-based proteins like beans, wheat-free whole grains, and small amounts of cooked vegetables and cheese.
  • Stay hydrated during the day with water, coffee, and tea.

Phase II – Week 2: “High Fat”

  • For 20-hours each day (Undereating Period): Snack very lightly on broth, raw fruits and vegetables, hard-boiled eggs, vegetable juice and dairy.
  • For 4-hours each day (Overeating Period): Start with a salad with oil and vinegar dressing.
  • Then eat a large meal of lean animal protein, cooked vegetables and at least one handful of nuts.
  • No grains or starches are eaten during this phase.
  • Stay hydrated during the day with water, coffee, and tea.

Phase III – Week 3: “Concluding Fat Loss”

This complicated phase cycles between days of high protein-low carbohydrate and high carbohydrate meals.

Start with a high carb day for 1-2 days, then switch to a high protein-low carb day for 1-2 days and alternate for a week.

On high carb days:

  • For 20-hours each day (Undereating Period): Snack very lightly on broth, raw fruits and vegetables, hard-boiled eggs, vegetable juice and dairy.
  • For 4-hours each day (Overeating Period): Start with a salad with oil and vinegar dressing.
  • Then eat a large meal of cooked vegetables, one main carbohydrate (corn, pasta, barley, oats, potatoes), and small amounts of animal protein.
  • Stay hydrated during the day with water, coffee, and tea.

On high protein – low carb days:

  • For 20-hours each day (Undereating Period): Snack very lightly on broth, raw fruits and vegetables, hard-boiled eggs, vegetable juice and dairy.
  • For 4-hours each day (Overeating Period): Start with a salad with oil and vinegar dressing.
  • Then eat 8-16 ounces of animal protein and cooked non-starchy vegetables.
  • No grains or starches should be eaten during the high-protein-low carb phase III overeating period.
How to do the warrior diet?

Beyond Phase III – What Comes Next

Hofmekler recommends that once you cycle through the first three phases, you start over from the beginning.

Warrior Diet Summary

The warrior diet is a variation of intermittent fasting that cycles 20-hour periods of undereating with 4-hour periods of overeating.

It is sometimes called 20/4 fasting.

It’s based on the feast or famine type of eating that our prehistoric ancestors engaged in and the battle all day, feast at night eating that Spartan and Roman warriors followed out of necessity.

Since there is little scientific evidence to backup the validity of this diet, check with your health professional before beginning.

Depending on your goals and lifestyle, this type of intermittent fasting may be perfect for you.

Others may find it difficult to follow.

My two cents: If you’re looking for intermittent fasting for weight loss, there are better, easier, scientifically proven methods to try. 🙂

If you think that being She-Ra or He-Man and doing the Warrior diet may be too much for you, I encourage you to look at other methods of intermittent fasting.

If you’re curious, download my free intermittent fasting guidelines for beginners. ⬇️⬇️⬇️


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