3 Week Diet : Shed Up to 23 Pounds in 21 Days

By Mizpah Matus B.Hlth.Sc(Hons)

The 3 Week Diet was created by nutritionist, personal trainer, and author Brian Flatt.

This program comes with a money-back guarantee and promises weight loss results between 12 and 23 pounds in 21 days.

3 week diet- Brian Flatt

Brian Flatt claims that dieters may also experience a range of other benefits with this diet including:

  • Loss of stubborn body fat.
  • Decreased cellulite.
  • Increased energy.
  • Improved cholesterol levels.
  • Better muscle tone.
  • Healthier skin and hair.
  • Faster metabolism.

3 Week Diet For Fast Weight Loss

Flatt says that people who undertake this diet lose an average of 12 to 23 pounds of pure body fat. Some dieters have experienced losses as high as 33 pounds.

According to The 3 Week Diet, your results will depend on your dedication and the amount of effort you put into the diet.

If you want to lose even more weight you also have the option to continue the diet beyond the 21-days.

How to Burn Stubborn Body Fat

The 3 Week Diet utilizes 5 techniques to specifically target body fat.

  1. Reducing Calories.
  2. Intermittent Fasting.
  3. Lowering Carbohydrate Intake.
  4. Exercise.
  5. Strategic Supplementation.

Each method alone can have a significant effect so you do not have to incorporate all of them. However, when you implement them all together, you will lose weight rapidly.

The Three Phases of This Diet

Each week, you will begin a new phase. All of the phases are low in carbohydrates and calories. The purpose is to maximize fat loss early on while gradually introducing more whole foods into your diet.

Eventually, you will progress towards a nutritionally balanced and complete diet, to maintain a healthy weight for life.

The 3 Pound Rule

When you complete The 3 Week Diet or have achieved your goal weight, you will continue to weigh yourself every day.

At any time if you are three pounds or more above your target weight you should begin Phase 1 immediately. Continue on Phase 1 until you get back to your target weight, which usually just takes one or two days.

This allows you to enjoy “cheat” meals occasionally while ensuring you maintain your weight loss.

Recommended Foods

Dieters can expect to eat the following foods:
Whey protein, chicken, turkey, beef, fish, eggs, cream cheese, asparagus, beets, cabbage, artichoke, squash, broccoli, carrots, celery, kale, mushrooms, onions, peppers, spinach, tomato, cauliflower, avocado, macadamia nuts, almonds, pumpkin seeds, sunflower seeds, olive oil, butter, mayonnaise, balsamic vinegar.

Sample Meal Plan

Meal #1: Noon

3 poached eggs
Sautéed spinach, peppers and mushrooms

Meal #2: 4pm

2-3 oz tuna
Steamed asparagus and cauliflower

Meal #3: 8pm

2-3 oz turkey
Steamed broccoli and carrots

Exercise 20 Minutes Per Day

The program comes with a workout manual that can help you double your results when combined with the diet.

The fitness routine was created for people who don’t have time to go to the gym every day. The manual also includes a gym workout for those who are dedicated to their exercise regime.

To gain fat-loss benefits you need to workout for just 20-minutes a day, 3 to 4 days a week. This is because burning stubborn body fat is burned most effectively with intense, full body exercises – rather than long cardio sessions

The manual also includes the Midsection Miracle Workout, which contains the only two exercises you need to get 6-pack abs.

Costs and Expenses

The 3 Week Diet is available in PDF format for $47.

Learn more and get instant access to this diet here.


  • Offers rapid weight loss results.
  • Based on scientific research.
  • Comes with a money-back guarantee.
  • Uses regular grocery store foods and readily accessible nutritional supplements.
  • Addresses the importance of a positive mindset and maintaining motivation for successful weight loss.
  • Once you achieve your goal weight you can eat whatever you like.


  • Very restrictive program that includes dramatic calorie restriction.
  • Involves intermittent fasting, which may result in some degree of hunger and physical discomfort.
  • Requires elimination of carbohydrate foods including fruit, starchy vegetables, legumes and whole grains.
  • Encourages the use of caffeine and nicotine pills, which may have negative side effects, especially in sensitive or health-compromised individuals.

Rapid Weight Loss Can Result

The 3 Week Diet involves a reduced calorie, low-carbohydrate diet, which is combined with intermittent fasting.

This approach produces rapid weight loss results by restricting the body’s fuel supply and encouraging the mobilization of body fat.

It is a very restrictive program that will likely involve some experience of hunger and discomfort. As such it will appeal to highly motivated dieters who are looking for a plan for rapid weight loss.

Filed in Diet Reviews


  1. Andree Joyce

    Is this diet available in Canada
    (Ottawa,Ontario) if yes, how much more would it cost for the 3 week plan?

  2. Veronica

    What is the a meal plan for days 9-11 about the full fat this seems a little complicated as well when you have to add protein to your meals

  3. Barb

    It says in the article: “Once you achieve your goal weight you can eat whatever you like.” That is not true. If you are on a restricted diet and afterwards you eat normally you will gain the weight back.

    • Hannah

      I purchased the plan, and after the 21 days you need to eat at ur bmr or below of u still want to lose weight. As long as you r not eating over ur bmr calories, u will not gain weight back.

  4. Catrina Massey

    HELLO there my sister woke me up this morning challenging me to a grapefruit diet, now I happen to be a major foodue so how this whole diet thing is going to work for me is truly unknown. Lol but im going to give it a try. Hopefully it is successful.

    • Lisa

      Be careful because grapefruit can interfere with many medications!!!

      • Heather Prefontaine

        I can’t believe that u would actually recommend nicotine pills and then not list the negative side effects. You just lost any potential business from me. I think I will buy Dr. Phil’s book instead.



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