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What is the 4 Day Diet?

Angela Atkinson
Angela Atkinson

According to Dr. Ian Smith, the author of The 4 Day Diet, successful weight loss is only 20 percent physical. The other 80 percent, he says, is all in a person's head. Many people do not fully prepare themselves mentally when they begin a weight loss journey, and Smith says that factor is the biggest mistake a person can make.

The 4 Day Diet brings to light the concept of retraining the brain for successful weight loss and health maintenance. It also claims to help eliminate boredom-induced failure. One major component, for example, encourages dieters to change their menus every four days so they don’t lose interest.

A glass of diet soda, which is allowed in the 4 day diet.
A glass of diet soda, which is allowed in the 4 day diet.

Contrary to popular belief, The 4 Day Diet is not a quick fix. In fact, it is touted as the beginning of a lifestyle change that is designed to enhance metabolism. The diet consists of a series of seven different four-day modules, which Smith says will boost the body’s metabolism by forcing it to constantly readjust to new conditions. Each module is designed to serve a different purpose, but all are directed toward helping dieters lose weight and stay in shape in a healthy manner.

During the Induction module, a body detox is advised. This phase is restrictive, limiting refined carbohydrates, proteins, sugars, and fats. Cardiovascular exercise is also introduced.

The Pace module of the 4 Day Diet allows low-fat yogurt.
The Pace module of the 4 Day Diet allows low-fat yogurt.

The Transition module slowly reintroduces the previously restricted food groups back into the diet. During this phase, dieters may drink coffee or diet soda and water; eat legumes, salads, and other raw fruits and vegetables; and eat fish and lean poultry. Two reduced calorie snacks are allowed each day, and cardiovascular exercise is continued.

Next, the Protein Stretch module is designed to combat weight loss plateaus. As this phase increases proteins and healthier fats within the diet, it theoretically fires up the metabolism, allowing a person to burn calories at a faster rate. Plus, the exercise portion is changed during this module by slightly reducing cardiovascular activity and adding light weightlifting. Allowed foods include protein shakes, eggs, turkey bacon, raw and cooked vegetables, legumes and brown rice, and sandwiches made with lean meat.

The 4 day diet can help with weight loss.
The 4 day diet can help with weight loss.

The Smooth module reintroduces formerly forbidden favorite foods back into the diet. Though this phase does not eliminate the need to eat healthy, it allows certain indulgences like burgers and pizza. Exercise includes weightlifting and cardiovascular workouts.

Next, the Push module is a somewhat restrictive phase designed to drive the metabolism higher and promote weight loss. During this segment of The 4 Day Diet, dieters are allowed to eat mostly lean protein, eggs, legumes, fruit, and green leafy vegetables. Cardiovascular activity is increased and weightlifting takes a backseat to walking at least 8,000 steps each day.

The Pace module is less restrictive than its predecessor. It allows a person to consume cereals, low-fat yogurt, lean meat and fish, vegetables, legumes, and brown rice. Exercise includes both weight training and cardiovascular workouts.

Fish is part of the 4 Day Diet.
Fish is part of the 4 Day Diet.

Next, the Vigorous module is the final piece of the puzzle. This phase is designed to help dieters shed the last few pounds. Food choices include soups and salads, lean meat and poultry, raw and cooked vegetables, and low fat yogurt. Exercise during this segment of the program centers strictly on cardiovascular activities.

The modules are flexible, too. They can be used in succession for one month, or can be tailored for individual needs. In general, Smith recommends that the first two modules are followed in order, but the remaining five can be used in any sequence.

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Discussion Comments


@turkay1-- Hey! My sister is doing the diet right now. She was at the dietician earlier for blood tests, but she is doing the diet on her own. She just got the book and I personally haven't read it but I think it has all the necessary instructions in there.

As for the modules, if you haven't reached your goal yet, I believe you go back to previous modules and do it again, but not necessarily in the same order. You can pretty much keep doing them as long as you feel you need to. But I heard Dr. Ian Smith on TV and he was recommending people to stop at a weight that they can maintain in the long term, so you're not supposed to overdo it.

I don't know what happens after you reach your goal. I suppose you end the four day diet but continue eating healthy and exercise to maintain it. My sister has definitely learned a lot so far. She is always taking about foods and exercises that boost the metabolism. Like with any diet, that knowledge stays with you, so if you want, you can continue what you've learned from the program.


So what happens after the vigorous module? If you lost the weight you wanted to lose, do you end the 4 day diet and continue on to something else?

What if you haven't reached your weight loss goal after the final module? Do you go back to module one?

And can I get some feedback from dieters who have done the 4 day diet? How did you start? Did you do it all on your own or with advice from a dietician?


This sounds like a really great diet program. I especially like that "forbidden foods" are allowed during some stages of the diet. I think that would prevent people from feeling deprived and overeating the forbidden foods in excess after the diet and gaining all the pounds back.

I did a diet where I did not have any bread or sweets for one and a half years. I lost all the excess weight and looked great but I was so deprived when I ended the program that I started eating these things everyday. After two years, I'm back where I started.

It sounds like this wouldn't happen with the four day diet since I get to have some of those foods during dieting.

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    • A glass of diet soda, which is allowed in the 4 day diet.
      A glass of diet soda, which is allowed in the 4 day diet.
    • The Pace module of the 4 Day Diet allows low-fat yogurt.
      By: creative soul
      The Pace module of the 4 Day Diet allows low-fat yogurt.
    • The 4 day diet can help with weight loss.
      By: mocker_bat
      The 4 day diet can help with weight loss.
    • Fish is part of the 4 Day Diet.
      By: Kondor83
      Fish is part of the 4 Day Diet.