Home > Diets > Calorie Counting Diet Navigation    
User Rating


of people who tried this diet like it

+ - Tried it? Rate it!
out of 100
based on 34 reviews
Slim Fast 321

The SlimFast 321 Diet Plan Review (UPDATED 2020): Don't Buy Before You Read This!

Slim down on this easy and flexible weight loss plan.

Top Rated Diets of 2020
What is it?

The SlimFast 321 Diet Plan is said to be a clinically studied weight loss strategy offering prepackaged foods. It offers SlimFast’s meal replacements, bars, pre-packaged foods, and it recommends a 500 calorie meal.

It’s said one can eat around 6 times a day with mostly SlimFast products making the bulk of the diet. The company mentions that SlimFast formulas have more protein and fiber with less sugar than its competitors.  An estimated 1 to 2 pounds of weight loss a week are claimed to be possible. This review will go over customer reviews, the quality ofingredients, and whether or not it’s an effective weight loss plan. Our experts compiled a comprehensive list of the top 10 diet plans available now. Click here to see what diet plans were ranked as the best for weight loss.

Do You Know the Best Diets of 2020?

The SlimFast 321 Diet Plan Ingredients and Side Effects

Here are some of the ingredients found in the SlimFast foods:

Artificial Color


Calcium Caseinate

Milk Protein Concentrate

Cellulose Gel

Mono and Diglycerides



FD&C Yellow 5

FD&C Yellow 6

Soy Protein Isolate

FD&C Red #3

Nonfat Dry Milk Powder

Corn Syrup

Confectioner’s Glaze

Artificial Color: Man made chemical which can be extracted from common allergens, tar, and oil. It has no nutritional value, and is only added to give a unique color to the food.

Natural solutions for weight loss are available from the top 10 highest rated diet plans.

Cellulose Gel:Thickener and stabilizer found in things like detergents, laxatives, processed foods, and toothpaste. A study by Nature, the International Weekly Journal of Science found that it:

“induced low-grade inflammation and obesity/metabolic syndrome”

This type of inflammation can also increase the risk for chronic diseases.

Sucralose:Artificial sweetener that is around 1,000 times much sweeter than regular table sugar. A Duke University study found that it could lead to serious damage to health. It confirmed how sucralose:

“Alters Gut Microflora and Increases Intestinal P-Glycoprotein”

Healthy gut microflora is needed for many important functions, such as regulating the immune system. When rats were fed sucralose, there was an increase of P-glycoprotein. This is only created within the body when a potential contaminantneeds to be fought.

This artificial sweetener has been used controversially, since there have been a few studies showing how it might be potentially harmful. A comprehensive top 10 list of the best diet plans is available in this link.

Carrageenan:Thickener made from red seaweed. Studies have been performed which show it may potentially cause inflammation in the body.

One study by the University of Iowa found:

“cancer-promoting effects of undegraded carrageenan...widespread use of carrageenan in the Western diet should be reconsidered”

The clinical study advised to limit the use of this ingredient since it’s possible for it to lead to unwanted side effects. It also is only found in processed foods.

FD&C Yellow 5:Artificial food dye added to give foods a yellow color. It’s known to be one of the most allergy causing of all food colorings.

The Center for Science in the Public Interest has tried to ban this ingredient, due to its lack of nutritional value and potential for side effects.

FD&C Yellow 6:Food dye that can be extracted from things like petroleum and coal tar. The University of California, Los Angeles has found that:

“(Yellow 5 and Yellow 6) have been found to be contaminated with benzidene or other carcinogens.

Soy Protein Isolate:A 90% soy protein by weight extract. It’s often GMO and it can potentially lead to side effects such as:

         • Allergies, reduced testosterone, and increase estrogen.

• Reduced mineral absorption, increased risk for gout, and mood swings.

Soy also has what’s known as phytoestrogens, phytates, and goitrogens. This can potentially lead to unwanted side effects.

Corn Syrup:Processed sweetener that is extracted from corn, it’s a cheap sweetener often found in many processed foods.

There is also no book or guide to the SlimFast 321 Diet Plan, it essentially offers snacks, shakes, and a suggestion to eat a 500 calorie meal every day. This can be hard to sustain for some, as the only non-packaged foods allowed is one meal.

No recommendations are offered for what the 500 calorie meal should be. 500 calories is also not a lot for a full meal.

A guide of the top 10 best diet plans is offered via the link provided here.

EDITOR’S TIP: Combine this diet with a proven meal replacement such as 18 Shake for better results.

The SlimFast 321 Diet Plan Quality of Ingredients

Ingredients like artificial colors, food coloring, sucralose, soy protein isolate, carrageenan, and others are cheap to add and not necessary. These ingredients are cheap substitutes for more wholesome additives.

There’s a possibility for side effects and the basis of the diet is very simple. With the reduced calories it’s likely one will lose weight. However, this can be done with any low calorie foods. Many of the additives in SlimFast products aren’t actually proven good for the body.

The ingredients in the plan are artificial, processed and not natural. This makes this an unsuitable weight loss diet plan.

The Price and Quality of The SlimFast 321 Diet Plan

Prices can vary depending on where one buys their SlimFast brands from. A 4 pack of the high protein meal replacement sells for $6.93 on, the 4 pack of granola bars sell for $5.89, and the 100 caloriesnacksrange from $4.93 on Amazon.com.

Though inexpensive, the quality of ingredients is poor, and many customers have said that it does not suppress appetite.  Many artificial colors, thickeners, binders, and other processed ingredients are added. The kinds of ingredients added are poor and cheap to source.

The list of the top 10 diet plans is offered in a comprehensive list found here.

Business of The SlimFast 321 Diet Plan

The company is owned by Core Science Medica LLC. They can be reached via the following:

Phone Number: (561)833-9920

Address: 777 S Flagler Drive #1400

West Palm Beach, Florida 33401

The company had to recall its SlimFast shakes after it was fond to be contaminated with a potential toxin.  The FDA letter stated:

“The recall was initiated after the company conducted quality testing”

“recalling all… products in cans”

“possibility of contamination with Bacillus cereus, a micro-organism which may cause diarrhea and possibly nausea and/or vomiting”

This brand was sold nationwide, and was forced to be removed from store shelves. It’s unknown how this contaminationhappened, and there’s no statement on how this could have happened. A full refund was offered for any customers who purchased these contaminated products.

There are currently 52 complaints on their Consumer Affairs page.Customers complained about a lack of quality control, and of the prepackaged foods expiring faster than what were claimed.A top 10 list of the best diet plans can be found when you click this link.

EDITOR’S TIP: The top 10 list of the best diets is available here.

Customer Opinions of The SlimFast 321 Diet Plan

Here are some customer reviews of the products offered:

“you cannot sustain yourself on the 3-2-1 plan. Eating a shake and a bar… every day is just unsatisfying”

“don’t waste your time or money. You’ll want real food after a day”

“due to the high sugar content they are not weight loss products”

“It tasted like baby formula”

Many people found that the foods offered don’tsuppress appetite, and that it left them feeling extremely hungry and wanting to snack.

Some were concerned that the ingredient added to the foods are mostly artificial, high in sugar, and potentially harmful. These customers noted how the high amounts if sugar were likely to actually make weight loss harder. Sugar has no nutritional value, and it should be limited in those looking to lose weight and stay healthy.

People also repeatedly failed to see any weight loss.The top 10 rated diet plans are available in a comprehensive list found here.

Conclusion - Does The SlimFast 321 Diet Plan Work?

When deciding on whether or not to use The SlimFast 321 Diet Plan, it’s important to examine the kinds of ingredients and support offered. Many of the additives in their foods are high in sugar, or made from processed ingredients. Customers often complained that the meals were not satisfying, and that it was difficult to keep eating these types of foods. People considered the plan as not long lasting or effective for weight loss. There have also been issues with company recalls due to contaminations.

The highest rated diet plan of 2020 was found to be the 18Shake Diet. Customers mention it’s an effective and potent way to lose weight. It combines an all-natural metabolism booster made with clinically studied ingredients, as well as a high protein, appetite suppressing meal replacement.  There are no artificial ingredients, stimulants, binders, fillers, or cheap additives. There’s clinically studied ingredients found, and it has the combined benefit of fat burning and appetite suppression.

The supplements offered are both backed by a 30 day money back guarantee. Return is offered with no questions asked. Discover more information about the 18Shake Diet plan by following the link here.

How Does Slim Fast 321 Compare?
  • Product Name
  • User Rating
  • Easy to follow
  • Cheap Price
  • Fast Results
  • Slim Fast 321
  • 44 /100
  • .
  • .

> Leave Feedback

User Feedback

(Page 3 of 3, 44 total comments)


I have tried for ten years to lose even a couple of pounds with no success. Really. I didn't want to join a dieting group plan and I didn't want to keep track of points and I didn't want to buy meals. I bought two 6 packs of Slim Fast and in two weeks I lost 3 pounds. All I have done is eat a regular breakfast and lunch, and have a Slim Fast for dinner. Period. I am not hungry. Now, it has been a month and I've lost 7 pounds. HOORAY!

posted Aug 20th, 2010 9:01 pm


I am adding the slim fast into my diet because my wife didn't want to finish her's. But I do get up early and run for 2 miles or 30 mins before work everyday. Plus I'm putting the Insanity workout along with it. My goal is a 35 lbs loss. I drink the slim drinks , and or bars along with three other small meals no bigger than my fist. I'll keep an update weekly. Everyone keep it up!!

posted Jul 13th, 2010 6:36 pm



I'm due for my first weigh in on Wednesday, up to now i've found the plan easy to follow. At the moment Boot's have slimfast powder on special at half price so I've stocked up. I feel much better in myself, more energy and get up and go.

posted Jun 28th, 2010 6:12 am



I 'm on day 1 and I like it! I'm not naive about the fact that it isn't a long term plan AT ALL! However, I think it's a great plan for ladies who wanna drop some holiday pounds, and ease into a more long term eating plan. I'm using the website and it's really awesome that they give you options that aren't all Slim Fast products! I have my ending date as the middle of July so I think it's a good plan for a month or two but nothing more!

posted Jun 8th, 2010 10:57 am


Leave Feedback

Or, proceed without an account


Already a member?

BACKGROUNDBACKGROUND Start the Diet Now Advertisement

Slim Fast 321 is a three-step weight loss plan that offers both structure and flexibility.

The numbers three, two and one correspond to how many meals and snacks you will be eating throughout the day.

You can follow the Slim Fast 321 plan by registering for the diet on the Slim Fast website. Registration is free.

Here is how the plan works:

  • You have three, 100-calorie snacks, which can be either a Slim Fast 100-calorie bar or 100 calories worth of fruit, vegetables or nuts.

  • Next, you have two Slim Fast shakes or meal bars, each of which are worth about 300 calories. Finally, you have one 500-calorie meal per day.

  • The Slim Fast Slim Fast website provides you with a list of meal ideas, as well as a chance for you to chart your own progress and connect with others who are also trying to lose weight.

Slim Fast products can be found in grocery stores all over the country as well as ordered online.

Do You Know the Best Diet Pills of 2020?

  • Encourages portion control
  • Created by a well-recognized name in the meal replacement diet industry
  • Eating frequently throughout the day can curb feelings of diet deprivation
  • Website offers a host of supportive tools to help you reach weight loss goal
  • Encourages eating fruits, vegetables and lean proteins
  • Named #3 in the Best Commercial Diets by US News, 2011
  • Meal replacement diets have not demonstrated long-term weight loss success
  • Eating only Slim Fast products can lead to cravings for other foods
  • Plan lacks variety

The Slim Fast 321 Plan is a straightforward diet that encourages eating six portioned meals or snacks throughout the day.

Slim Fast is widely recognized for its line of meal replacement shakes and bars and this diet recommends eating two or more of these products every day.

Slim Fast shakes and bars are high in protein and fiber.

Here is a typical day on the Slim Fast 321 Plan:

  • Breakfast: One Slim Fast 321 Shake or a Slim Fast Bar
  • Snack: One-half of a banana, one pear or one Slim Fast 100-calorie Snack Bar
  • Lunch: One Slim Fast 321 Shake or a Slim Fast Bar
  • Snack: One medium apple, one cup of strawberries or one Slim Fast 100-calorie Snack Bar
  • Dinner: Grilled halibut with veggies, fish tacos, Asian beef salad
  • Snack: Two medium apricots or one Slim Fast 100-calorie Snack Bar

A two-week sample menu plan is included on the website as are portion guides for your one daily meal and sample meal ideas.


Exercise is an integral part of the Slim Fast 321 Plan. Regular exercise not just improves weight loss outcomes but it also contributes to overall wellness.

On the plan, you are encouraged to exercise on most days of the week, doing a combination of cardiovascular and strength-training exercises.

You can track your exercise progress on your online progress calendar.


The Slim Fast 321 plan is not as easy as 1-2-3, but it is a straightforward diet that requires you adhere to the frequenting noshing of Slim Fast products and the characteristic "sensible meal."

While this plan gets high remarks for its structure and encouragement of portion control, it falls short on variety and its reliance on fruit. Therefore, for those who are diabetic, you should talk to your doctor before starting this plan.

Common MisspellingsCommon Misspellings

slimfast 321, slim fast 123, slim-fast 321, 321 slimfast, 321 slim fast, slim fast three two one, slim fats 321

Whats better than
Slim Fast 321?