The 4 Day Diet
The 4 Day Diet claims that by varying your diet and physical activity every four days, you will lose more weight. But our experts say that's not necessarily the case.
By Krisha McCoy, MS | Medically reviewed by Pat F. Bass III, MD, MPH
The 4 Day Diet is an eating and exercise plan devised by Ian K. Smith, MD, from the TV show “Celebrity Fit Club.” You may be disappointed to find out that The 4 Day Diet isn't a four-day quick fix, but rather another twist on trying to psych out your metabolism.
The 4 Day Diet: How It Works
The 4 Day Diet consists of a series of four-day segments called modules. When you are on this diet, you will change the way you eat and exercise every four days. Dr. Smith says that this style of eating will help you lose weight since it will force your body to adjust to changes in your diet and exercise, which will result in more calories burned. "Each module has a different goal and purpose," says dietitian Elisa Zied, MS, a spokesperson for the American Dietetic Association and author of Nutrition at Your Fingertips.
The modules include:
- Induction. The induction module is designed to help your body detoxify. On an induction day, you might drink coffee, low-sugar freshly squeezed lemonade, and water; eat green leafy vegetables, a salad, fruit, low-fat yogurt, and brown rice; and do cardiovascular exercise for 40 minutes.
- Transition. During the transition module, you reintroduce all the food groups back into your diet. The transition days allow you to drink coffee, diet soda, and water; eat raw vegetables, fruit, legumes, lean poultry or fish, salad, and two low-calorie snacks (for example, 20 raw almonds and 1 cup grapes); and do some type of cardiovascular activity.
- Protein Stretch. The protein stretch increases your protein intake to help you avoid weight-loss plateaus. A protein stretch day allows you to drink coffee and water; eat eggs, turkey bacon, a protein shake, fruit, raw vegetables, a lean protein sandwich, legumes, brown rice, and cooked vegetables; and do 30 minutes of cardiovascular exercises and 20 minutes of light weight lifting.
- Smooth. Now you will be allowed to eat some of your favorite foods that were previously restricted. During this module, you will eat a mostly healthful diet, but will be allowed to eat indulgence foods like pizza, burgers, French fries, and chili. Your exercise will consist of both cardiovascular activity and weight lifting.
- Push. The push module is a strict eating plan that is intended to jump-start your body into losing weight. You will eat mostly eggs, lean protein, legumes, fruit, and salad; increase the amount of cardiovascular activity you do; and wear a pedometer and take 8,000 steps per day.
- Pace. In the pace module, you will eat in a manner that is less strict than the push module. Foods consumed on a pace day may include cereal, low-fat yogurt, fish or lean meat, salad, vegetables, brown rice, legumes, and two low-calorie snacks. Both cardiovascular activity and weight training will be performed during the pace module.
- Vigorous. This final module is intended to help you lose the last few pounds. You will eat low-fat yogurt, fruit, raw vegetables, soup, salad, lean meat, and cooked vegetables, and focus on cardiovascular activity.
These modules can be followed in succession for one month, or you can customize your own program, based on your schedule and individual preferences. It is recommended that everyone do the first two modules in order, and then rearrange the other five however they want.
The 4 Day Diet: The Pros
As with almost any diet, there are both benefits and drawbacks to following The 4 Day Diet. Some benefits include:
- Incorporation of exercise. "[Smith] does incorporate exercise, which I think is very responsible of him," says Zied, referring to exercise as "the other side of the equation for weight control." Following the strengthening exercises in the 4 Day Diet may help prevent some of the muscle wasting that often accompanies weight loss.
- Healthy, balanced eating tips. "Some of these modules are healthy and pretty balanced," said Zied. "People can pick and choose one or more of the modules if they just want to try that for a little while," she says. Zied notes that the smooth module is a particularly good way of eating.
The 4 Day Diet: The Cons
Potential drawbacks of The 4 Day Diet include:
- No evidence behind the "four-day" claim. "The author of this book is suggesting that you'll lose weight by varying your calorie intake every four days," says Zied, "but I don't think there is really any scientific basis to that assumption." Evidence from the National Weight Control Registry suggests that people who follow a relatively regular routine of healthful eating and physical activity are most successful in losing weight and keeping it off. "For long-term weight loss, you need to be very consistent in the way you eat," says Zied.
- Potential for nutrient deficiency. Even though the 4 Day Diet incorporates many healthful foods, its restrictions put dieters at risk of consuming too few whole grains and dairy products.
- Risk of regaining the weight. Like any diet that changes the way you eat for a specified amount of time, your chances of regaining the weight when the diet is over are very high. "The research shows very clearly that really restrictive diet plans [in which] you are doing something that you don't normally do — that is a 180-degree turnaround from your normal routine — are not going to hold up," says dietitian Katherine Tallmadge, MA, national spokesperson for the American Dietetic Association and author of Diet Simple: 192 Mental Tricks, Substitutions, Habits & Inspirations.
While the 4 Day Diet includes many healthful recommendations, its restrictive nature may make it difficult to follow and could even put you at risk of becoming deficient in calcium, vitamin D, and other nutrients.