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 was not published until 2002.

Since then, Gittleman 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 people who are looking to lose weight fast.

However, the company’s claims that the plan will “detoxify” the body and cleanse the liver, as well as its 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. Because it recommends unnecessary supplements, shakes, and extreme calorie restriction, this plan is a poor choice for long-term, sustainable weight loss.

Pros

  • cuts out less nutritious foods such as those high in added sugar and refined carbs
  • emphasizes intake of foods high in fiber, protein, and healthy fats

Cons

  • includes several very low calorie phases
  • encourages unhealthy and unrealistic weight loss goals
  • pushes the use of unnecessary and pricey supplements
  • uses unfounded claims for marketing purposes
  • expensive and unnecessary

The company’s most popular plan is the New Fat Flush Plan, but the company offers three different plans.

Customers can choose a plan based on their needs and goals and then purchase the plan, as well as any additional reading materials and supplements, through the website.

The three weight loss plans available through the Fat Flush website are:

We look at how each one 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: In this “detox” phase, dieters consume only smoothies and supplements for 3 days. This is meant to “set the stage” for weight loss.
  2. The 2-week Fat Flush: For the next 2 weeks, dieters drink 8 glasses, or 64 ounces (oz), of watered-down cranberry juice, called cran-water, daily. They also 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 2–4, 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 two shakes per day made with the Fat Flush Body Protein sold on the website.

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

The plan requires dieters to take Fat Flush Kit supplements twice per day.

Fat Flush for Life

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

According to the company, 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. It also suggests that dieters consume Fat Flush Supplements and specialty beverages daily.

The pricing for each plan is as follows:

  • The New Fat Flush Plan: Bundles containing “The New Fat Flush Plan” book and a 30-day Fat Flush Kit start at $109.96.
  • Smoothie Shakedown: Bundles containing a 2-week guide, 2 canisters of Fat Flush Body Protein, and a 30-day Fat Flush Kit start at $167.16.

The “Fat Flush for Life” book is available for purchase on the company’s website for $15.80.

Customers can also purchase pricey supplements and protein powders on the website.

For example, the pea-and-rice-based Fat Flush Body Protein costs $69.50, which is much more expensive than most other pea- or rice-based protein powders on the market.

The website encourages customers to choose a plan based on the speed at which they would like to lose weight.

The Smoothie Shakedown is advertised as an “accelerated” weight loss plan, which allots users two smoothies and one meal per day. The New Fat Flush Plan is a four-phase plan that is supposedly meant to help people lose weight gradually and change their habits.

The Fat Flush for Life plan is marketed toward those who would like to maintain the weight they lost while using the New Fat Flush Plan or the Smoothie Shakedown. The company claims that the Fat Flush for Life gives users more variety by incorporating seasonal foods and recipes.

Once a person decides which plan is best for their needs and lifestyle, they can purchase the plan, along with additional supplements and tools such as journals and cookbooks, on the company’s website.

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 health benefits in addition to weight loss.

For example, losing excess weight in general can help lower blood sugar, blood pressure, and blood lipid levels, which can reduce disease risk (1).

In addition, increasing your intake of healthy sources of fats, protein, and fiber can benefit your overall health (2, 3).

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

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

First, the plan relies on cutting calories drastically, which results in metabolic changes that can make it difficult to maintain weight loss long-term (4, 5).

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 such diets with weight regain over time (6).

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

Phase one of the Fat Flush Plan provides around 1,200 calories per day, which is far too few for most people (7).

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.

Most health experts agree that losing that much weight in such a short time 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 such as:

  • low energy
  • feelings of deprivation
  • headaches
  • irritability

This is why most health professionals recommend creating only a small calorie deficit, which can help people lose weight slowly — yet sustainably — while minimizing metabolic changes that make it difficult to maintain weight loss long-term (8).

The plan also encourages people to take several supplements, claiming that 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 who are taking 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 (9, 10).

What’s more, the Fat Flush Plan suggests that “hidden weight gain factors” such as 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 (11).

Lastly, the Fat Flush Plan is expensive and unnecessary.

There are many affordable, evidence-based ways to promote healthy, sustainable weight loss without extreme calorie restriction, “detoxing,” or liquid cleanses.

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 (7).

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 weight loss and fat loss while preserving muscle mass (12, 13).

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

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

  • added sugar and artificial sweeteners
  • caffeine
  • alcohol
  • grains, breads, pastas, and 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:

  • Non-starchy vegetables: broccoli, spinach, tomatoes, eggplant, etc.
  • Proteins: eggs (up to two per day), chicken, shrimp, cod, whey protein, etc.
  • Fruits: grapefruit, oranges, apples, strawberries, etc.
  • Herbs and spices: cayenne, fennel, cinnamon, ginger, etc.
  • Flax oil: 1 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 a person chooses to follow. This is only the protocol for phase one of the Fat Flush Plan.

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

  • Upon rising: Long Life Cocktail
  • Before breakfast: 8 oz of hot water with lemon juice
  • Breakfast: asparagus and mushroom omelet
  • Lunch: salmon with lemon and garlic, broccoli, and a mixed green salad
  • Dinner: beef and veggie shepherd’s pie
  • Snacks: 1/2 grapefruit, 1 apple

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

The Fat Flush diet is not a good choice for safe, sustainable weight loss. The Fat Flush plans are unnecessarily restrictive and expensive and rely on arbitrary rules that are not based on sound science or medical findings.

Even though the Fat Flush programs, such as the Smoothie Shakedown, will likely result in some weight loss, you’re likely to gain back any weight you lose unless you transition to a more sustainable eating pattern.

Instead of using expensive programs like the Fat Flush Plan, you can lose excess body fat and improve overall health by using evidence-based methods and eating patterns like the following:

  • Work with a healthcare professional: A healthcare professional such as a registered dietitian can help you create a way of eating that fits your specific health needs and encourages healthy weight loss. Studies show that working with a dietitian is an effective way to lose weight (14).
  • Try following a Mediterranean-style diet: The Mediterranean diet encourages the consumption of fiber-rich vegetables, fruit, and beans; healthy fat sources like olive oil and seeds; and protein sources like seafood. The Mediterranean diet has been linked to weight loss and long-term healthy weight maintenance in many studies (15).
  • Increase your fiber and protein intake: High protein and high fiber diets are effective for weight loss because foods high in fiber and protein help keep you full. You can try adding a source of protein and fiber to every meal and snack and swapping foods low in protein and fiber for more satisfying options (15).

In general, you’ll want to choose a dietary pattern that you can follow for a long time and that does not make you feel overly restricted.

A healthy weight loss diet should provide the nutrients and calories you need to stay satisfied and energized throughout the day while encouraging fat loss by creating a small, sustainable calorie deficit.

Keep in mind that you can also create a calorie deficit by increasing your physical activity level.

What are fat flushing foods?

There’s no such thing as a “fat-flushing” food, and there are no foods that can “flush” your body of excess fat. The only way to lose weight is to take in fewer calories than you burn on a daily basis, whether by changing your diet or by increasing your physical activity.

However, there are “fat-flushing” over-the-counter and prescription medications that bind to fat in your digestive system. These products can lead to unwanted side effects like uncontrollable diarrhea and nutrient malabsorption. They are generally not recommended as a healthy way to lose weight (16).

If you’re interested in exploring this option, be sure to consult a healthcare professional first.

Keep in mind that you do not want to “flush fat” out of your body or reduce the absorption of fat in your digestive system. Fat is an important nutrient that’s necessary for vitamin absorption, cellular function, and other functions in your body (17).

What is a 3-day fat flush?

The 3-Day Fat Flush, which is advertised as a “detox,” involves consuming nothing but smoothies, raw vegetables, and supplements for 3 days. The 3-day program is meant to “set the stage” for weight loss.

The company encourages customers to use this program to “kick-start” the Fat Flush weight loss program or to overcome weight loss plateaus.

What is the 24-hour fat flush?

According to Gittleman’s website, the 24-hour fat flush can be used to “reset” after the holidays. The 24-hour fat flush entails skipping solid foods for 24 hours.

During the 24-hour period, you would consume only Gittleman’s orange, pomegranate, and cranberry-based Holiday Detox Juice and hot lemon water.

This is completely unnecessary and will not result in any meaningful weight loss. There’s no need to forgo solid foods for 24 hours when trying to lose weight.

Instead, skipping meals for 24 hours will likely lead to extreme hunger and may cause you to overeat when the 24-hour period ends.

Online reviews of the Fat Flush program are mostly positive. Customers note that, although the plans are difficult, they can be effective for short-term weight loss. This is not surprising, as any plan that drastically cuts calories can promote quick weight loss.

However, these plans are often not sustainable, and you will likely regain any lost weight once you return to typical eating habits.

Negative reviews say the diet is very restrictive and hard to follow and that the programs are extremely expensive.

The Fat Flush Plan is not accredited by the Better Business Bureau and does not have a profile on Trustpilot.

The Fat Flush Plan is a fad diet that involves 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, this plan’s use of unnecessary supplements and shakes and promotion of low calorie dieting make it a poor choice for long-term, sustainable weight loss.

If you’re looking for a way to reach and maintain a healthy body weight, you can work with a knowledgeable healthcare professional such as a registered dietitian to come up with a plan that works for your specific needs and lifestyle.