What Is the 4-Hour Body Diet?

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The 4-hour body diet program, laid out in the bestselling book The 4-Hour Body, relies on lean protein, legumes, and non-starchy vegetables to spark what it claims can be dramatic weight loss. It's simple to follow—the diet urges you to eat the same foods every day, which makes meal planning easy.

Overall, the diet likely will help you lose some weight. However, it doesn't teach you anything about how to keep weight off long-term. It also omits several critical food groups, which could lead to nutritional deficiencies.

What Experts Say

"This low-carb diet makes outlandish claims, such as “lose 20 pounds of fat in 30 days.” Experts agree that eliminating grains, fruit, most dairy, and certain vegetables—along with encouraging binge days—can lead to nutrient imbalances and unhealthy eating patterns."

Chrissy Carroll, RD, MPH


The 4-hour body program was created by Timothy Ferriss, an investor and New York Times bestselling author who also wrote The 4-Hour Workweek (four hours seems to be a theme). The book claims to contain "the collective wisdom" of elite athletes and prestigious physicians, plus hundreds of hours of experimentation.

The book, originally published in 2010, is peppered with weight loss and general health and wellbeing anecdotes that are fun to read but hard to believe in many cases. In addition to the diet program, The 4-Hour Body also includes tips on reducing your needed hours of sleep, stepping up your muscle gain, and improving your sex life.

Still, fans of the program (and there are many; it has a loyal following) maintain the weight loss diet part works. (Some of the other, more outlandish claims in the book don't get good reviews.)

The weight loss program detailed in The 4-Hour Body includes five "rules" that the book claims will enable you to lose 20 pounds of body fat in 30 days. The program, alternatively called the slow-carb diet, supposedly can allow people following it to reduce their overall body fat percentage to less than 10%. According to author Ferriss, "The Slow-Carb Diet... is the only diet besides the rather extreme Cyclical Ketogenic Diet that has produced veins across my abdomen, which is the last place I lose fat."

How It Works

When following the 4-hour body program, you'll eat mainly protein, legumes, and non-starchy vegetables—often the same meals over and over again. You'll also get one "cheat" day per week when you're encouraged to eat whatever you want in whatever quantities you desire.

What to Eat

Compliant Foods

  • Chicken breast or thigh

  • Beef

  • Fish

  • Pork

  • Conventional egg whites with one or two whole eggs for flavor

  • Two to five whole organic eggs

  • Legumes, including black beans, pinto beans, red beans, and soybeans

  • Vegetables, including spinach, mixed cruciferous vegetables, asparagus, peas, broccoli, green beans, and lettuce

  • Tomatoes

  • Avocados (limited to one cup or one meal per day)

  • Red wine (limited to two glasses per day)

  • Nuts (limit to just a few per day)

  • Olive oil and butter for cooking

  • Olive oil and balsamic vinegar for salad dressing

Non-Compliant Foods

  • Bread

  • Rice

  • Cereal

  • Potatoes

  • Pasta

  • Tortillas

  • Breaded, fried foods

  • Sugar-sweetened beverages

  • Candy

  • Chips

  • Cake and cookies

  • Dairy products (with the exception of cottage cheese)

Ferriss details five rules that he says are the key to the program. They include:

  1. Avoid "white" carbohydrates. This includes all bread, rice (including brown rice), cereal, potatoes, pasta, tortillas, and fried food with breading.
  2. Eat the same few meals over and over again. To do this, you can mix and match from a limited list of ingredients: lean chicken, beef, fish, or pork; eggs; various types of legumes; and vegetables that are limited to spinach, mixed cruciferous vegetables, asparagus, peas, broccoli, and green beans. You're allowed to eat as much of those food items as you like, but the program urges you to choose three or four meals and repeat them. Legumes are an essential part of the program since they are calorically dense.
  3. Don't drink calories. The program calls for drinking "massive quantities of water," plus as much unsweetened tea, coffee, and low- or no-calorie beverages as you want. You're allowed two tablespoons of cream in your coffee. Milk, normal soft drinks, and fruit juice are banned. The diet allows up to two glasses of red wine per night.
  4. Don't eat fruit. "Humans don't need fruit six days a week, and they certainly don't need it year-round," The 4-Hour Body states, noting that people living 500 years ago in Europe didn't eat fresh fruit in the winter. Tomatoes and avocados (which technically are fruit, even though some might think of them as vegetables) are allowed under the diet, but no other fruit is allowed unless it's on a cheat day.
  1. Take one day off per week. Ferriss recommends Saturdays as what he calls your "Dieters Gone Wild" day: "I am allowed to eat whatever I want on Saturdays, and I go out of my way to eat ice cream, Snickers, Take 5, and all of my other vices in excess." By making himself a little sick on junk food one day per week, he says he doesn't want to consume any on the other six days. He also claims that dramatically increasing caloric intake in this way once per week increases fat loss by making certain that your metabolic rate doesn't drop. However, there's no real medical evidence for his assertion.

Recommended Timing

The diet plan recommends consuming four meals per day, all made up of the only allowed foods and spaced around four hours apart. Eat your first meal within an hour of awakening. Following that meal, you should have lunch during the early afternoon, a smaller second lunch in early evening, and then dinner in the late evening.

You should start the diet plan at least five days before your designated cheat day. For example, if you choose Saturday to cheat, then you should start the diet on a Monday. That will give you plenty of time to acclimate to the diet before you go wild.

Resources and Tips

There's absolutely no calorie counting on the diet—in fact, you're allowed (and encouraged) to eat as much protein and legumes at mealtimes as you wish. The program discourages snacking, saying that if you're hungry, you should add protein and legumes during your regular meals. However, if you do want a snack, you're allowed to have a few nuts or a handful of carrot sticks.

Ferriss notes that breakfast is the hardest meal for most to modify since many people count on cereal and toast to get them moving in the morning. "Moving to slow carbs and protein requires a more lunch-like meal for breakfast," he says, adding that his most frequent breakfast consists of eggs, lentils, and spinach. A more typical breakfast on the diet might include eggs with turkey bacon and sliced tomatoes. Lunches and dinners generally are either stir-fries or salads with a hefty dose of legumes and protein.

On the 4-hour body program, you're encouraged to eat the same foods again and again. This helps you stick to the diet, in theory, since it simplifies shopping and preparation. According to Ferriss, "I've found that the more variety you attempt, the more likely you are to quit, as everything from shopping to cleanup becomes more complicated."

Wherever possible, Ferriss urges eating out for your cheat meals, and no matter what, throwing out all "bad' food before the next morning: "If there is bad food in your house, you will eventually eat it before your 'off' day, also called 'reverse Lent' by some followers."


Vegetable Substitutions

The diet allows you to substitute any vegetable for those listed. Ferriss notes that cauliflower often gets set aside mistakenly because it's white, and the diet doesn't allow white foods. However, cauliflower is allowed, since it's a vegetable.

Lacto-Ovo Vegetarian

It's possible to follow the 4-hour body program as a lacto-ovo vegetarian (a vegetarian who eats eggs and dairy products). However, you still should avoid milk products, with the exception of cottage cheese. Ferriss also advises against refined soy products, including all soy milk and isolated soy protein supplements.

Gluten-Free and Dairy-Free

The gluten-free diet and/or a dairy-free diet wouldn't be a problem on the 4-hour body program since the program already bans all grain products and most dairy products.

Pros and Cons


  • Diet is heavy on vegetables

  • Includes plenty of fiber

  • Avoids highly-refined flour and sugar

  • Skips candy, chips, and soda


  • Food choices are limited

  • May contain too much protein

  • Could lead to nutritional deficiencies

  • May not be healthy for those with certain medical conditions


Diet Is Heavy on Vegetables

Few people eat enough vegetables. The 4-hour body diet encourages you to consume as many as you want, especially nutritional powerhouses such as broccoli, asparagus, and spinach.

Includes Plenty of Fiber

Fiber is another important nutrient, and many of us don't get enough. That won't be the case if you follow the 4-hour body plan, since virtually every meal will include legumes and vegetables. Although recipes for the diet vary, you should clock in at around 30 grams of fiber per day or more.

Avoids Highly-Refined Flour and Sugar

"White" foods, such as highly-refined grain products and sugar, aren't good for you. Therefore, the 4-hour body diet's plan to eliminate these is a good one. However, it's a bad idea to eliminate all grains, including healthy whole grains, as the diet calls for you to do.

Skips Candy, Chips, and Soda

As with highly-refined grain products and sugar, most candy, chips and sugary soda has no place in a healthy diet. In addition, the 4-hour body program's focus on drinking plenty of water, plus unsweetened beverages, is healthy.


Food Choices Are Limited

The 4-hour body program views the limited food choices as an advantage, and in fact urges followers to eat the same foods over and over again. Most people likely will find that limiting and boring, which could make the diet tough to stick with long-term.

May Contain Too Much Protein

Although the 4-hour body program states that it includes "slow carbs," not "no carbs," it also features a lot of protein... unlimited amounts, if that's what it takes to keep hunger at bay. It's a bad idea to eat too much of any nutrient, including protein—nutritional guidelines call for consuming between 10% and 35% of your daily calories in protein.

Could Lead to Nutritional Deficiencies

The 4-hour body diet eliminates foods that are nutritional powerhouses, including virtually all fruit and dairy. This could lead to deficiencies in particular vitamins and other nutrients, including: vitamin D and calcium (found in dairy), and B vitamins such as folic acid (found in grains and fruit).

May Not Be Healthy If You Have Certain Medical Conditions

If you have kidney disease, you likely should steer clear of the 4-hour body diet program, since it relies on so much protein—people with kidney disease should limit their protein. You also should beware of the diet if you have osteoporosis, since it's so low in calcium and vitamin D. Even if you don't have pre-existing health conditions, you should talk with your doctor before starting any diet program, including this one.

How It Compares

The 4-hour body diet program doesn't fit neatly into a diet category since it's not low-calorie, low-fat, or low-carb. It does bear some similarities to certain low-carb programs.

USDA Recommendations

The U.S. Department of Agriculture's MyPlate tool, which provides recommendations for a healthy diet, calls for getting more than one-quarter of daily calories from whole grains, plus nearly one-quarter of calories from fruit. It also urges consumption of low-fat and non-fat dairy, since they're great sources of calcium and other nutrients.

Clearly, the 4-hour body diet falls short in all three of those areas: it contains virtually no fruit, no grains, and practically no dairy (cottage cheese is allowed). The diet program does contain ample fiber and enough (potentially too much) lean protein.

The 4-hour body diet practically forbids calorie-counting, but it's typical to consume around 1,200 to around 2,000 calories per day when following the diet, depending on how much of the recommended lean meat and legumes you eat.

Similar Diets

Atkins Diet

When people think of diets that allow them to eat all the food they want, their minds may turn quickly to the Atkins diet—in earlier versions of Atkins, you could have as much protein and fat as you could stomach (later versions of the diet have provided suggested serving sizes).

The 4-hour body diet is similar to early Atkins versions in that it doesn't limit your food intake, but does limit your food choices. Both diets ban grains and most fruit. Still, the 4-hour body diet is much higher in carbohydrates and fiber than Atkins, since it encourages legumes in unlimited quantities.

Paleo Diet

The paleo diet aims to restore the eating habits of our remote, pre-agricultural ancestors. When you follow the paleo diet, you focus mainly on vegetables, meats, and lower-sugar fruits that would have been available to hunters and gatherers thousands of years ago. Grains are banned, as are highly processed foods, and, often, dairy.

The paleo diet shares some similarities to the 4-hour body diet: both programs eliminate grain products and most dairy. However, the paleo diet also eliminates legumes, while the 4-hour body diet relies heavily on them. In addition, the paleo diet allows fruit, such as berries and apples, and the 4-hour body diet program does not.

A Word from Verywell

You'll probably lose some weight if you follow the 4-hour body diet blueprint—the program has a devoted following online, and quite a few of those people say it worked for them. However, it's not sustainable long-term, since you're likely to get bored with eating the same foods over and over again, and you could develop nutritional deficiencies by omitting entire categories of food from your meal plans.

Before you start any diet—the 4-hour body diet or another program—you should touch base with your physician to make sure the program you've chosen is right for you. In addition, it never hurts to talk to a dietitian, who can help you choose healthy foods as you're slimming down.

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Article Sources

  • Ferriss, Timothy. The 4-Hour Body: an Uncommon Guide to Rapid Fat-Loss, Incredible Sex, and Becoming Superhuman. Harmony Books, 2012.