What Is the 4-Hour Body Diet?

Four-hour body diet

 Verywell / Debbie Burkhoff

At Verywell, we believe there is no one-size-fits-all approach to a healthy lifestyle. Successful eating plans need to be individualized and take the whole person into consideration. Prior to starting a new diet plan, consult with your health care provider or a registered dietitian, especially if you have an underlying health condition.

The 4-Hour Body diet, as presented in the bestselling book, "The 4-Hour Body," claims that a diet emphasizing lean protein, legumes, and non-starchy vegetables can lead to rapid and significant weight loss. The diet requires you to eat the same foods every day, which proponents say helps to simplify meal planning.

The 4-Hour Body diet was created by Tim Ferriss, an angel investor and author of several bestselling books including "The 4-Hour Workweek" and "The 4-Hour Chef." The 4-Hour Body program positions itself as a resource of "collective wisdom" from elite athletes and prestigious physicians and claims that "thousands of hours of experimentation" led to its success as a viable weight loss plan.

The book, originally published in 2010, is a combination of weight loss tips and anecdotes pertaining to general health and well-being. In addition to the diet program, the book also includes tips on reducing your needed hours of sleep, increasing your muscle mass, and improving your sex life.

Proponents of the weight loss program (of which there are many) claim the diet works, but reviews about the eating plan and strategy are often mixed and some have questioned Ferriss's credibility as a health guru. For example, the weight loss program detailed in "The 4-Hour Body" book includes five "rules" to follow to lose 20 pounds of body fat in 30 days, which is not a realistic rate of weight loss for most people.

While the program will likely help you lose some weight, it won't teach you anything about how to maintain that weight loss long-term. It also omits several critical food groups, which could lead to nutritional deficiencies, and promotes unhealthy habits like binge eating.

Ferriss is known for his unconventional ideas on diet, fitness, and health, which have amassed a large following from advocates and also subjected him to criticism from experts.

For instance, in the "4-Hour Body," he touts the Slow-Carb Diet, an eating plan that promises rapid weight loss by restricting refined carbohydrates, starchy vegetables, and sugar. While this strategy can lead to weight loss, the plan includes an unusual recommendation to binge eat one day a week on whatever you want in order to "hack" the body's metabolism. As Ferriss writes, the Slow Carb Diet is "the only diet besides the rather extreme Cyclical Ketogenic Diet (CKD) that has produced veins across my abdomen, which is the last place I lose fat."

The 4-Hour Body diet restricts a number of healthy food groups and encourages unhealthy eating habits. Learn about the pros and cons of the 4HB program and why most nutrition experts would probably recommend other strategies to support weight loss and health.

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

What Can You Eat?

If you follow the 4HB diet you will eat mainly animal protein and eggs, legumes such as lentils and different types of beans, and non-starchy vegetables like spinach, broccoli, asparagus, and green beans. You are allowed to eat as much as you like of any of the foods that fall into the approved groups. You'll pick three or four meals that you prefer and repeat them over and over for the duration of the program, which simplifies preparation and planning depending on what you choose to eat. 

"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," Ferriss writes.

Fruit, with the exception of avocados, and refined "white" carbohydrates are restricted on the diet. These include all types of bread, pasta, white and brown rice, tortillas, and fried foods. However, you are also encouraged to binge eat anything you want in whatever quantities you desire one day a week, which is not smart nutritional advice.

The 4HB program, sometimes called the "slow-carb diet," claims to reduce overall body fat percentage to less than 10%.

What You Need to Know

The diet plan recommends consuming four meals per day consisting of only the allowed foods. You'll eat your first meal within an hour of awakening, have lunch during the early afternoon, a smaller second lunch in the early evening, and then dinner in the late evening. Each meal is spaced about four hours apart.

Ferriss notes that breakfast is often the hardest meal to modify since many people count on cereal and toast in the morning. "Moving to slow carbs and protein requires a more lunchlike meal for breakfast," he writes, 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-frys or salads with a hefty dose of legumes and/or meat for protein.

The diet plan should begin at least five days before your designated binge day. For example, if you choose to binge on Saturday, then you should start the diet on a Monday. The idea is to give yourself ample time to acclimate to the diet before you indulge in whatever you want for a day.

Whenever possible, Ferriss advises eating out for what he refers to as your "cheat meals," or in other words, a meal outside of the required foods of the diet. He also suggests throwing away all "bad" food associated with your binge before you resume the diet the next morning, since they don't comply with the diet. "If there is bad food in your house, you will eventually eat it before your 'off' day, also called 'reverse Lent' by some followers," he writes. (Since tossing away food is wasteful, perhaps it's worth considering not having those foods on hand at all and sticking with healthy, delicious foods instead.)

The following five rules are key to the 4-Hour Body diet plan:

  1. Avoid "white" carbohydrates. This includes all bread, white and brown rice, cereal, potatoes, pasta, tortillas, and any 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; 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 essential since they are calorie-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 not allowed. The diet also 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," Ferriss writes, noting that people living 500 years ago in Europe didn't eat fresh fruit in the winter. Tomatoes and avocados (which are technically fruits) are acceptable, but no other fruit is allowed unless it's on a "cheat day."
  5. Take one day off per week. Ferriss recommends choosing Saturday 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 won't want to consume any binge foods on the other six days. He also claims that dramatically increasing caloric intake once per week increases fat loss by ensuring that your metabolic rate doesn't drop. However, there's no real medical evidence to support this assertion.

There's no calorie counting on the 4HB diet and you're encouraged to eat as much protein for your meals as you wish. But the program discourages snacking and advises eating more protein during your regular meals to curb hunger. If you want a snack, you're allowed a few nuts or a handful of carrot sticks.

What to Eat
  • 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

What Not to Eat
  • 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)

Modifications

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" with the exception of cauliflower, since it's a vegetable.

Dietary Restrictions

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 and a little cream for your coffee. For those with a soy allergy or intolerance, refined soy products including soy milk and isolated soy protein supplements are also banned from the diet.

Those on a gluten-free diet and/or dairy-free diet should be able to tolerate the 4HB eating plan since the program already bans all grains and most dairy products. However, this diet would not work for those who need to follow a low-FODMAP diet, since legumes are a high FODMAP food.

Pros and Cons

Pros
  • Diet is heavy on vegetables

  • Includes plenty of fiber

  • Avoids highly-refined flour and sugar

  • Skips candy, chips, and soda

Cons
  • Food choices are limited

  • May contain too much protein

  • Could lead to nutritional deficiencies

  • May not be healthy for those with certain medical conditions

  • Eating schedule is very strict

  • Unlimited legume consumption may be problematic for some

Pros

Diet Is Heavy on Vegetables

The 4-Hour Body diet encourages you to consume as many veggies as you want, especially nutritional powerhouses such as broccoli, asparagus, and spinach.

Includes Plenty of Fiber

Fiber is an important nutrient that many Americans are lacking in their diets. But the 4-Hour Body includes fiber-rich legumes and vegetables at every meal. Depending on the recipes you follow, you could get up to 30 grams of fiber a day.

Avoids Highly Refined Flour and Sugar

"White" foods, such as refined grains and added sugars are limited in a regular balanced diet due to their high-calorie content and lack of fiber, so avoiding them is not necessarily a bad thing. However, whole grains are also excluded despite that they contain viable nutrients.

Skips Candy, Chips, and Soda

The diet does not allow sweets, chips, candy, and soda. These contain excess calories, unhealthy saturated fats, and added sugars and other ingredients that can cause weight gain and inflammation, which is linked to heart disease. However, the program does technically allow you to eat them on binge days.

Cons

Potential for Gas and Bloat

Legumes are encouraged in unlimited quantities on this diet. While they can be a healthy part of any balanced diet, they often cause gas and bloat in those who are not used to eating a lot of fiber. Fiber should be increased gradually in small quantities, paired with ample amounts of water.

Food Choices Are Limited

The 4-Hour Body program views the limited food choices as an advantage and urges followers to eat the same foods over and over again. Most people will likely find that limiting, 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 unlimited amounts of protein to help keep hunger at bay. But eating too much protein can cause you to take in excess calories. As a result, your body could start to store more fat, which can lead to weight gain.

Could Lead to Nutritional Deficiencies

The 4-Hour Body diet eliminates foods that are nutritional powerhouses, including virtually all fruit and dairy, which limits your intake of certain vitamins and minerals.

May Create Unhealthy Eating Habits

The strict schedule on this diet may prevent people from developing intuitive eating habits and force them to eat when they are not hungry or avoid eating when they are hungry.

The "cheat day" allows for eating anything in any quantity, which can promote disordered eating—particularly binge eating.

May Not Be Healthy If You Have Certain Medical Conditions

If you have kidney disease, you should probably steer clear of the 4-Hour Body diet program, since people with kidney disease should limit their protein. You should also be cautious if you have osteoporosis since the diet is very 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.

Is the 4-Hour Body Diet a Healthy Choice for You?

The U.S. Department of Agriculture's 2020–2025 Dietary Guidelines for Americans recommends a variety of fruits, vegetables, whole grains, lean protein, dairy products, and healthy fats for a balanced diet. Federal guidelines also suggest limiting foods and beverages with higher amounts of added sugars, saturated fat, and sodium. 

The amount of fruit and whole grains a person should eat each day varies based on their age, sex, weight, and level of activity. According to the USDA, you might need around 1–2 cups of fruit and between 3–8 ounces of grains a day, at least half of which should be whole grains. The USDA also recommends low-fat and non-fat dairy products, since they're great sources of calcium and other nutrients. The 4-Hour Body diet falls short in all three of these areas.

The program does not require calorie-counting, but it's typical to consume around 1,200 to around 2,000 calories per day when following this diet—though it will depend on how much meat and legumes you eat. The recommended limit for weight management is around 2,000 calories a day. For weight loss, 1,500 calories a day is usually advised, but that number varies based on the individual. Use this calculator tool to determine your daily calorie needs.

The 4HB eating plan contains virtually no fruit, grains, or dairy (cottage cheese is allowed). While the program does provide plenty of fiber, it may encourage too much protein. The diet does not adhere to federal dietary guidelines and is not recommended as a strategy to support weight management and overall health.

Health Benefits

Certain aspects of the 4-Hour Body diet, such as avoiding refined carbohydrates, may lead to fat loss. The diet also encourages unlimited consumption of legumes, which are a great source of heart-healthy fiber (but may cause gas or bloat in some people).

A balanced diet encourages limiting and even avoiding junk food like chips, candy, and soda since saturated fat and added sugars are associated with obesity, inflammation, and chronic disease. While the 4-Hour Body diet discourages these foods, it does give the green light to binge on them one day a week.

Health Risks

While there are no common health risks associated with the 4-Hour Body diet, binge eating in any form is not sound nutritional advice and could lead to disordered eating.

Additionally, it's not a good idea to eliminate entire food groups such as whole grains since they are an important source of vitamins, minerals, and fiber. Though the eating plan advises unlimited protein consumption, it's unwise to eat too much of any nutrient, including protein. Nutritional guidelines typically call for around 10–35% of daily calories to come from protein. Consuming protein in excess may contribute to weight gain and cause other imbalances in the body.

Restricting entire food groups could lead to deficiencies in certain vitamins and other nutrients, including vitamin D and calcium (found in dairy) and B vitamins such as folic acid (found in grains and fruit).

Similar Diets

The 4HB diet program is neither a low-calorie, low-fat, or low-carb eating plan, but a unique combination of these diets. It also bears some similarities to other well-known low-carb programs. Here's how they compare.

Atkins Diet

When people think of diets that allow them to eat all the food they want, they might recall earlier versions of the Atkins Diet that allowed for as much protein and fat as a person could handle (later versions of the diet have 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 hunter-gatherer eating habits of our distant, pre-agricultural ancestors. When you follow the paleo diet, you focus mainly on vegetables, meats, and lower-sugar fruits. Grains are banned, as are highly processed foods, and in many cases, 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, while 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. The program has a devoted following, many of whom swear by the success of the eating plan. However, it's not a sustainable long-term approach to weight loss. You could develop nutritional deficiencies by omitting entire food groups and unhealthy eating habits from binging. Before you start any diet, it's a good idea to touch base with your physician to make sure the program you've chosen is right for you. In addition, you may want to speak to a registered dietitian who specializes in nutrition to help you reach your health goals.

Remember, following a long-term or short-term diet may not be necessary for you and many diets out there simply don’t work, especially long-term. While we do not endorse fad diet trends or unsustainable weight loss methods, we present the facts so you can make an informed decision that works best for your nutritional needs, genetic blueprint, and budget, and goals.

If your goal is weight loss, remember that losing weight isn’t necessarily the same as being your healthiest self, and there are many other ways to pursue health. Exercise, sleep, and other lifestyle factors also play a major role in your overall health. The best diet is always the one that is balanced and fits your lifestyle.

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Article Sources
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