What Is the Warrior Diet? The Intermittent Fasting Plan Reviewed

Medically Reviewed
fruits and vegetable snacks throughout the day
If you eat like a warrior, can you slay your day?Claudia Totir/Getty Images

These days, intermittent fasting is a household phrase, but back in 2002 when The Warrior Diet was first published, the idea of eating only during specific windows of time was a pretty new idea. Like paleo and similar diets, this eating plan is based on emulating the ways that our ancestors supposedly ate. In the case of the warrior diet, however, the emphasis involves not just what but also when our forebears were eating.

As with any intermittent fasting plan, the warrior diet limits the times during the day when you are permitted to eat, advocating a single meal a day. But is this way of eating effective for losing weight, and more importantly, is it safe and sustainable in the long term? This guide will tell you everything you need to know.

What Is the Warrior Diet?

The warrior diet is based on a book of the same name written by Ori Hofmekler, and it claims to “switch on your biological powerhouse for high energy, explosive strength, and a leaner, harder body.”

The plan is a version of intermittent fasting that alternates a period of fasting with a small window of time in which to eat all of the day’s calories. The warrior diet promotes exercising and undereating during the day, when our nomadic and hunter-gathering ancestors would likely be busy finding food rather than eating it. For exercise, the diet encourages short workouts that emphasize strength training, especially for your joints and back, and high-velocity exercises such as jumps, kicks, and sprints.

During the day, raw vegetables and fruit, small amounts of protein, and beverages including water, natural juices, coffee, and tea are permitted. The book states that this period should not last more than 16 to 18 hours, but many newer variations of the diet encourage undereating or not eating at all for 20 hours.

Then in the evening, you eat one large meal. There are no restrictions on how much or what kind of food you eat, so you can include any protein, fat, and carbs you want.

Common Questions & Answers

Is the warrior diet the best kind of intermittent fasting plan?
In general, experts recommend plans in which you fast once or twice a week and eat normally on the other days, or in which you eat in at least an eight-hour window and fast for 16 hours, to give you enough time to nourish yourself properly.
Are the warrior diet and OMAD the same?
The warrior diet is similar to OMAD, or one meal a day, which is a more extreme version in which you eat all your calories for the day in a single two-hour period, usually around dinnertime.
Can you lose weight on the warrior diet?
Possibly. Studies have found that intermittent fasting can help some people lose weight, however, it was no more effective than reducing calories overall, regardless of when you eat.
What can you eat on the warrior diet?
In the daytime undereating phase, you can eat fresh fruits and vegetables and small amounts of protein. During the evening eating window, you can eat what you like, although refined sugar and refined, processed pastries are not allowed.
How long is it safe to follow the warrior diet?
Experts are reluctant to put a time frame on the warrior diet since they don’t think it’s a healthy, sustainable choice for most people.

How Does the Warrior Diet Work?

The diet claims that fasting produces fat-burning hormones, allows your body to use protein more efficiently, stabilizes your blood sugar levels, increases testosterone and growth hormone levels, and allows amino acids to act favorably on the brain. Consequently, at the end of the undereating phase, your body is positioned to eat a lot of food without gaining body fat. The author writes, “This is the best time to eat as much as you want and enjoy this wonderful sense of freedom.”

Diets that are centered around intermittent fasting, like the warrior diet, may also put your body into ketosis, according to research published in October 2017 in Ageing Research Reviews. Ketosis, the basis of the keto diet, is a metabolic state in which your body gets its fuel from fat rather than sugar.

But experts are skeptical about the benefits of the warrior diet. “The plan encourages a swing from starvation to bingeing, and it’s not really something a body could or should withstand without consequence. It makes your body either starve and feel really deprived, or it makes your body work so hard to try to get rid of that giant eating binge,” says Bonnie Taub-Dix, RDN, author of?Read It Before You Eat It: Taking You From Label to Table.

What Are the Potential Health Benefits of the Warrior Diet?

No research has specifically studied the warrior diet. But scientists have identified some potential health benefits of intermittent fasting:

It’s not clear whether the warrior diet would confer the same benefits as other types of intermittent fasting. And even if it does, this trendy version of the diet might not be your best choice. “I don’t want to discount intermittent fasting, because there’s some good research behind it,” says Samantha Cassetty, a registered dietitian based in New York City and the coauthor of Sugar Shock. “But this is an extreme version where you’re only eating in a small window. It’s unhelpful, unrealistic, and unsustainable for most people.”

What Are the Potential Weight Loss Effects of the Warrior Diet?

It’s possible to lose weight on the warrior diet since you might be taking in fewer calories. Intermittent fasting can lead to weight loss, according to a?review and meta-analysis of six studies, however, it wasn’t more effective than reducing calories without timing your meals.

“If you’re doing this diet for weight loss, the reason it might be working is because it is reducing your calorie load. There’s no magic to it,” Cassetty says.

It can be difficult to eat a day’s worth of calories or more in a short window of time. Of course, it isn’t impossible to do so, and you could also gain weight if you eat an excessive amount during your daily window, Taub-Dix points out.

Foods to Eat and Avoid on a Warrior Diet

In general, the diet does not restrict foods or food groups, although it does emphasize whole, unprocessed foods whenever possible. During your daytime undereating phase, if you feel you need to eat something, you can have:

  • Fresh raw fruits and veggies
  • Up to 6 ounces of protein, such as eggs, chicken or turkey breast, fish, shellfish, plain low-fat or nonfat yogurt or kefir, cottage cheese, whey protein, nuts, or protein powder
  • Freshly squeezed fruit and veggie juices
  • Water
  • Coffee (a small amount of milk is fine but no sugar)
  • Tea

During the diet’s eating window, it is recommended that you start your meal with raw vegetables, then add protein and cooked veggies, and finally whole-grain carbohydrates. Include a variety of tastes, textures, aromas, colors, and temperatures. You can eat:

  • Vegetables
  • Fruits
  • Eggs
  • Milk, cheese, and other dairy products, preferably low fat or nonfat
  • Butter
  • Lean meat and poultry
  • Fish
  • Beans
  • Nuts and seeds
  • Legumes
  • Cheese
  • Oils, except hydrogenated and partially hydrogenated oils and margarine
  • Whole-food carbohydrates, such as carrots, beets, pumpkin, and squash
  • Grains such as rice, oats, quinoa, barley, and millet
  • Fermented foods
  • One glass of wine

Refined sugar and refined, processed pastries are not allowed on the warrior diet.

A 7-Day Sample Menu for the Warrior Diet

On the warrior diet, you might eat raw vegetables and fruits and a little bit of protein during the day, then a green salad and one of these larger meals at night.

Day 1

Curry chicken in tomato broth, steamed vegetables, and low-carb pumpkin cheesecake

Day 2

Baked red snapper, zucchini fries, and crepe blintzes

Day 3

Pepper beef and broccoli and warm raspberries with yogurt

Day 4

Egg white omelet with black beans and berries with maple syrup and red wine

Day 5

Angel hair rice pasta with tomato sauce and eggs and papaya gelatin

Day 6

Turkey-stuffed peppers and a green citrus smoothie

Day 7

Chicken chipotle flatbread and low-carb pecan pie

Pros and Cons of the Warrior Diet

The warrior diet isn’t expensive. It doesn’t require you to buy specific products, so it shouldn’t add to your grocery budget. And it’s not that complicated — you don’t have to count calories or macros, or track your food.

It’s not for everybody, however. Taub-Dix says that it’s particularly risky for people with disordered eating, people with diabetes, children, women who are pregnant or lactating, and older adults. She doesn’t recommend it for anyone, and she says if you want to try it, you should talk to your doctor or dietitian first.

If you decide to try the warrior diet, you may need to figure out how you’ll manage social situations and family activities that include meals outside of your eating time. “When any eating plan restricts you from socializing or enjoying meals with friends and family, I think that’s a red flag,” Cassetty says.

The small window of eating time may make it difficult to get the nutrients you need. Cassetty pointed to protein, which ideally you want to eat throughout the day to help rebuild your muscle tissue. “This type of calorie restriction can also trigger stress, make you preoccupied with food, make you hungry and irritable, and promote headaches,” she says. And if you have kids, it’s not a good eating plan to model for them, since it signals that there’s something wrong with eating meals at routine times.

It might be hard to time your exercise with your eating. “If you’re exercising in the morning, that could put you at risk of fainting, dizziness, nausea, headache, or injuring yourself,” Cassetty says.

And if you’re going to restrict your eating time, eating earlier in the day is preferable since that’s when your metabolism is most efficient, according to a study published in?March 2021 in Biomolecules.

Resources We Love: Warrior Diet

Favorite Book

'The Warrior Diet: Switch on Your Biological Powerhouse for High Energy, Explosive Strength, and a Leaner, Harder Body'

This is the original book that launched the warrior diet

Favorite App

Window

Use this app to track your intermittent fasting meal windows.

Favorite Recipes

Warrior Lifestyle

This site has a host of resources to try if you’re following the warrior diet.

Favorite Podcast

The Warrior Diet Episode on 'The Intermittent Fasting Podcast'

Take an hourlong dive into the ins and outs of the warrior diet.

Summary

The warrior diet is a type of intermittent fasting that mimics the eating patterns of our warrior ancestors, who ate little or nothing during the day and filled up in the evenings. It features a daily cycle of undereating and overeating. If you want to try intermittent fasting, dietitians prefer versions that aren’t as strict.

Editorial Sources and Fact-Checking

  • Harris L, Hamilton S, Azevedo LB, et al. Intermittent Fasting Interventions for Treatment of Overweight and Obesity in Adults: A Systematic Review and Meta-Analysis. JBI Database of Systematic Reviews and Implementation Reports. February 2018.
  • Varady K, Cienfuegos S, Ezpeleta M, Gabel K. Cardiometabolic Benefits of Intermittent Fasting. Annual Review of Nutrition. October 2021.
  • Shetty AK, Kodali M, Upadhya R, Madhu LN. Emerging Anti-Aging Strategies — Scientific Basis and Efficacy. Aging and Disease. December 2018.
  • Haupt S, Eckstein M, Wolf A, et al. Eat, Train, Sleep — Retreat? Hormonal Interactions of Intermittent Fasting, Exercise, and Circadian Rhythm. Biomolecules. March 2021.
  • Faris MA, Kacimi S, Al-Kurd RA, et al. Intermittent Fasting During Ramadan Attenuates Proinflammatory Cytokines and Immune Cells in Healthy Subjects. Nutrition Research. December 2012.
  • Nencioni A, Caffa I, Cortellino S, Longo V. Fasting and Cancer: Molecular Mechanisms and Clinical Application. Nature Reviews: Cancer. November 2018.
  • Arnason TG, Bowen MW, Mansell KD. Effects of Intermittent Fasting on Health Markers in Those With Type 2 Diabetes: A Pilot Study. World Journal of Diabetes. April 2017.
  • Mattson MP, Longo VD, Harvie M. Impact of Intermittent Fasting on Health and Disease Processes. Ageing Research Review. October 2017.
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