The Fat Flush Plan is a type of diet and “detox” regimen. The company advertises the plan as a way to “cleanse the body for lasting weight loss.”

Nutritionist Ann Louise Gittleman developed the Fat Flush Plan in 1988, though the popular Fat Flush Plan book wasn’t published until 2002.

Since then, Ann Louise has created multiple programs under the Fat Flush umbrella. She sells weight loss plans, supplements, and cookbooks through her website, fatflush.com.

These plans are popular among those looking to shed extra pounds fast.

However, claims that the plan will “detoxify” the body, including cleansing the liver, and the promotion of “fat burning” supplements, liquid meal replacements, and more, have drawn criticism from the medical community, and for good reason.

Diet review scorecard
  • Overall score: 1.8
  • Weight loss: 2.5
  • Healthy eating: 1.75
  • Sustainability: 1.5
  • Whole body health: 1.5
  • Nutrition quality: 2.25
  • Evidence-based: 1.5

BOTTOM LINE: This is a fad diet. By recommending unnecessary supplements, shakes, and extreme calorie restriction, this plan is a poor choice for long-term, sustainable weight loss.

The most popular plan is The New Fat Flush Plan, but there are three main types. Customers choose a plan based on their needs and goals.

There are three different weight loss plans offered through the Fat Flush website:

We look at how each type works below.

The New Fat Flush Plan

This is the most popular plan. It consists of four phases meant to “increase metabolism, flush out bloat, and speed up fat loss.”

The four phases are as follows:

  1. 3-day ultra Fat Flush tune-up: A “detox” where you only have smoothies and supplements for 3 days, which is meant to “set the stage” for weight loss.
  2. The 2-week Fat Flush: For the next 2 weeks, dieters drink 8 glasses (64 oz.) of watered down cranberry juice called cran-water daily, take Fat Flush Kit supplements, and follow a low calorie, low carb diet.
  3. The metabolic reset: In this phase, dieters reintroduce gluten-free carbs, while still using Fat Flush Kit supplements and cran-water.
  4. The lifestyle eating plan: This phase aims to maintain long-term, lasting weight loss.

During phases 2 through 4, dieters drink a long life cocktail every morning, which consists of cranberry juice, water, and ground flax.

The Fat Flush Kit supplements include:

Smoothie Shakedown

The Smoothie Shakedown is another plan offered on the Fat Flush website.

When following this plan, dieters drink 2 shakes per day made with Body Protein sold on the website.

They also consume one high protein, low carb meal, and low carb snacks like hard-boiled eggs throughout the day.

The plan requires you to take Fat Flush Kit supplements twice a day.

Fat Flush for Life

The company advertises the Fat Flush for Life as a way to optimize long-term weight loss.

They say this plan lets you “take advantage of your body’s natural response to the seasons” and focuses on seasonal eating patterns.

Overall, the Fat Flush for Life program is low carb and suggests that Fat Flush Supplements as well as specialty beverages be consumed daily.

Customers choose the plan that they want and then purchase the plan, as well as any additional reading materials and supplements, through the website.

Summary

There are three main types of Fat Flush diet plan, ranging from short term to long term. Customers choose a plan based on their needs and goals.

The pricing for each plan is as follows:

  • The New Fat Flush Plan: Bundles containing The NEW Fat Flush Plan book plus a 30-day Fat Flush Kit start at $90.95.
  • Smoothie Shakedown: Bundles containing 2-week guide plus 2 canisters of Full Body Protein and a 30-day Fat Flush Kit start at $133.77.
  • Fat Flush for Life: Bundles containing the Fat Flush for Life book plus a 30-day Fat Flush Kit start at $85.95.
Summary

The prices of Fat Flush plans vary. Bundles start at around $90.

Many people have reported that the Fat Flush Plan has helped them lose weight. This isn’t surprising, because any diet that creates a calorie deficit can promote weight loss (1).

What’s more, the diet promotes weight loss methods such as cutting refined carbs and added sugars and increasing intake of protein and fiber.

All of these actions have been associated with fat loss and improvements in body composition (2, 3, 4).

However, just because a diet is likely to promote weight loss doesn’t mean it’s necessary or safe.

Summary

This diet can encourage weight loss, but not necessarily in a healthy way.

Because the Fat Flush Plan cuts out many foods that can negatively affect health, including added sugar, refined carbohydrates, and processed foods, following this plan is likely to result in other health benefits aside from weight loss.

For example, losing excess weight in general can help reduce blood sugar, blood pressure, and blood lipid levels, which can help reduce disease risk (5).

In addition, increasing your intake of healthy sources of fats, protein, and fiber can benefit overall health (6, 7).

However, people can also achieve these potential health benefits by following any healthy dietary pattern. They’re not specific to the Fat Flush Diet.

Summary

The Fat Flush Plan cuts out many foods that can negatively affect health, including added sugar, refined carbohydrates, and processed foods.

Although following the Fat Flush Plan will likely result in weight loss, the plan has some significant downsides.

First, the plan relies on cutting calories drastically, which results in metabolic changes that can make maintaining long-term weight loss difficult (8, 9).

For example, restrictive low calorie diets can lead to:

  • loss of muscle mass
  • increased feelings of hunger
  • reduced daily calorie expenditure

This is why studies have consistently linked them with weight regain over time (10).

Parts of the Fat Flush Plan and the Smoothie Shakedown and are very low in calories.

Phase one of the Fat Flush Plan provides around 1,200 calories per day, which is much too low for most people (11).

The Smoothie Shakedown provides even fewer.

The Smoothie Shakedown website says people can “lose up to 20 pounds in 2 weeks” and encourages people who have “more than 50 pounds to lose” to follow the Smoothie Shakedown for up to 4 weeks.

The majority of health experts would agree that this amount of weight loss in such a short time period is unhealthy and unrealistic.

This rapid weight loss will result in the loss of muscle mass, which decreases the number of calories you burn on a daily basis.

Plus, this extreme restriction will likely result in negative side effects, like:

  • low energy
  • feelings of deprivation
  • headaches
  • irritability

This is why most health professionals recommend only small caloric deficits to achieve slow — yet sustainable — weight loss while minimizing metabolic changes that make long-term weight loss maintenance difficult (12).

In addition to this, the plan encourages people to take a slew of supplements, claiming they have “fat burning” and “detoxifying” benefits. There’s no scientific evidence to support their use.

Also, some herbal supplements used in the Weight Loss Formula supplement can be dangerous for people on certain medications.

For example, both dandelion and milk thistle may inhibit certain enzymes in the body and may interact with common medications, including Warfarin and Plavix (13).

What’s more, the Fat Flush Plan suggests that “hidden weight gain factors” like liver toxicity, a “messy” microbiome, parasites, and “low quality” bile are among the main underlying causes of weight gain.

Although some of these factors are loosely based on research findings, such as the association between an altered microbiome and obesity, most of the claims are completely unfounded (14).

Lastly, the Fat Flush Plan is expensive and unnecessary.

There are many other affordable, evidence-based ways to promote healthy, sustainable weight loss that don’t involve extreme calorie restriction, “detoxing,” or liquid cleanses.

Summary

The plan encourages extreme calorie restriction, along with unnecessary supplements and smoothies.

Cutting calories drastically results in metabolic changes that can make maintaining long-term weight loss difficult.

During the 2-week phase one Fat Flush Plan, people are supposed to avoid the following foods:

  • added sugar and artificial sweeteners
  • caffeine
  • alcohol
  • grains, breads, pastas, starches
  • dairy
  • highly processed foods
  • trans fats, processed vegetable oils, and fried foods

During the 2-week phase one of the Fat Flush Plan, people are encouraged to consume the following foods:

  • Non-starchy vegetables: broccoli, spinach, tomatoes, eggplant, etc.
  • Proteins: eggs (up to 2 per day), chicken, shrimp, cod, whey protein, etc.
  • Fruits: grapefruit, oranges, apples, strawberries, etc.
  • Herbs and spices: cayenne, fennel, cinnamon, ginger, etc.
  • Flax oil: one tablespoon twice daily
  • Beverages: Long Life Cocktail, cran-water, hot lemon water
  • Sweeteners: stevia

Keep in mind that food rules vary depending on the meal plan the person chooses to follow. This is only the protocol for phase one of the Fat Flush Plan.

Summary

People are encouraged to avoid added sugars, refined carbs, grains, and pastas, and breads. The plan encourages some non-starchy vegetables, proteins, and fruits.

Here is a sample meal plan for phase one from the Fat Flush website:

  • Upon rising: Long Life Cocktail
  • Before breakfast: 8 ounces hot water with lemon juice
  • Breakfast: Asparagus and mushroom omelette
  • Lunch: Salmon with lemon and garlic, broccoli, and a mixed green salad
  • Dinner: Beef and veggie shepherd’s pie
  • Snacks: ½ grapefruit, 1 apple

During phase one, dieters must take the Fat Flush Kit supplements and drink 64 oz. of cran-water daily.

Summary

The Fat Flush website offers sample menus like the one above.

The Fat Flush Plan is a fad diet that promotes the use of restrictive dieting practices to promote rapid weight loss.

Some foundations of the diet, such as cutting out added sugar and reducing intake of refined carbs, are supported by research.

However, the use of unnecessary supplements and shakes and the promotion of low calorie dieting make this plan a poor choice for long-term, sustainable weight loss.

If you’re looking for a way to achieve and maintain a healthy body weight, work with a knowledgeable healthcare provider like a registered dietitian to come up with a plan that works for your specific needs and lifestyle.