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The 4 Day Diet

The Promise

This isn't a 4-day crash diet. It's actually a month-long program that you tackle in 4-day bursts. And you can do anything for only 4 days at a time, right?

Before you start dieting with the 4-Day Diet by Ian Smith, MD, there's a little up-front work. You keep a food diary and record your exercise and your mood for 10 days before you even start the diet.

You also do a little self-evaluation, trying to figure out why you're overweight, why you've had problems losing weight, and what your challenges are.

Once you set a weight-loss goal, you start the actual diet. The diet is made up of seven phases that each last 4 days. Each phase has a different focus with lots of food choices, so you shouldn't get bored.

The seven phases go like this:

  1. Induction: This first phase is about getting rid of toxins by eating mostly fruits, vegetables, beans, and legumes.
  2. Transition: You start reintroducing foods without overdoing it.
  3. Protein Stretch: You’ll load up on protein, such as lean meats, fish, and eggs.
  4. Smooth: This is where you can "cheat" a little. You can add some pizza, pasta, burgers, or hot dogs. Just don't pig out.
  5. Push: This is a hard part. You’ll need all your mental energy to get through these 4 days of limited calories and at least an hour of cardio a day.
  6. Pace: You keep a steady exercise and balanced diet going.
  7. Vigorous: This one is the strictest part -- 4 days of mostly vegetables and fruit, plus lots of cardio.


What You Can Eat and What You Can't

Food choices vary between stages, but Smith keeps things simple with a list of foods and portions you can eat each day. Eat until you are satisfied but not stuffed.

The 4 Day Diet doesn’t say much about alcohol, other than it’s a temptation and you should practice the 80-20 rule. That means that if 80% of what you eat and drink is healthy and on the plan, and the remaining 20% is off the plan, you will still succeed in losing weight.

Level of Effort: Medium

Limitations: You may make smart substitutions for some of the foods on your daily list, but generally, you can’t eat high-fat, high-carb foods.

Cooking and shopping: You’ll cook or eat out as usual, as long as you stick to the guidelines.

Packaged foods or meals: No.

In-person meetings: No.

Exercise: Required. Each day has specific exercise goals including cardio, strength, and resistance training, ranging from about 40 to 70 minutes per day, excluding the occasional rest day.

Does It Allow for Dietary Restrictions or Preferences?

The 4 Day Diet is generally geared toward low-fat, low-salt foods. You can easily adjust it to meet gluten-free, vegetarian, or vegan needs. 

What Else You Should Know

Cost: You’ll spend roughly the same amount on groceries.

Support: No.

WebMD Medical Reference

Reviewed by Michael Dansinger, MD on December 11, 2013

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