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Slim Fast 321

The SlimFast 321 Diet Plan Review (UPDATED 2024): Don't Buy Before You Read This!

Slim down on this easy and flexible weight loss plan.

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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.

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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 2024 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?
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User Feedback

(Page 1 of 3, 44 total comments)


I have been on plan 6 weeks and had few hiccups as many of us do! I have so far lost 16.5lbs!!! I am more then happy! Going way to go yet but I will be continuing.

posted Jul 13th, 2018 2:06 am

Josette Sammut

Great taste

posted Apr 22nd, 2018 5:00 pm

Cheri newman

I have a question : what I want to know is .ca I have slimfast 321 with a meal instead of pop, juice ect.

posted Jan 26th, 2018 6:53 am

Daniel packer

Thanks to dr.mack201@gmail. com for his wonderful work, My girlfriend left a week before our vacation to be with another man. I was desperate to get her back when I found dr.Mack. I don’t know how I found him, I don’t remember. But, when I first saw the good testimonies about his wonderful work and after reading the Testimonies, I decided I had to try. after his spell, I got a text from my lover. And we started going back and forth by text, she asked to meet the next day. So we did, and that night we ended up sleeping together, and about a few days after we got back together. anyone who needs help, should email dr.mack. He is the best.

posted Dec 3rd, 2017 9:20 am

Pamela Kay Hendrix

I love the taste. And I've lost 3.5lbs already and I just started last week using it.

posted Mar 8th, 2017 12:40 pm



Can I eat the meal for Lunch and just have one shake for Breakfast and one for Dinner? Slim Fast Diet

posted Apr 12th, 2016 12:27 pm

barbara hillis

I think I'll stick to my doctor and our diet. Diet plans always leave me confused and frustrated.

posted Sep 25th, 2015 6:54 am

Amy Young


Back in the late 90s, I lost 40 lbs in a matter of months & my clothing just hing on me! The plan was very easy to follow, especially at work.

posted Aug 30th, 2015 11:06 pm



Drink Water....

posted Jul 9th, 2015 9:10 am

Irene Mannering


I like the taste of Slimright, especially the vanilla and I have been using it twice a day with a small meal at night, no snacks in between.Unfortunaely I have been feeling a bitg dizzy lately and wonder if I am pefrhaps being a bit drastic in mty efforts to slim. I am 5ft 9 inches tall and I am in my 80's, weigh 65 ks

posted Feb 15th, 2015 11:33 pm



I've done great on it. Then again, I don't like to eat much. I eat a bigger meal because I am a bigger girl and I intake around 1000 to 1200 calories a day instead of the barely 1000 they want you to eat. I may also eat a nutrition bar. Took me off my weight loss plateau.

posted Dec 11th, 2014 3:23 pm

Norma Cooper


Slim fast does work, as anything will if you are dedicated to it; I think on the 321 plan, it helps those with sweet tooths because it cuts your cravings. I too have statrd the plan this is my first day and i will pray for success and give it my all. i did the HMR prgram , but is was way! too costly, couldn't afford it.My friend was on the slim fast 321 plan and lost a great deal of weight, its all about being committed ; I know we can do this, lets work tpgether to accomplish our personal goals; please feel free to email me at anytime, I need the support as well as different variety of suggessions. My goal is to loose 100lbs, no slow healthy way with slim fast; i too will be eating my 500cal for lunch and sometimes switching for breakfast; dinner is when I will have my shake to avoid over eating too late as I work long hrs most of the time. Overweight people are despearte for fast change, I'm one of them, but we must condition our minds to think slow. Again we can do this, because I'm tired of feeling fat and can't fit into normal jeans. I will succeed with the 321 plan on Slimfast. We will succeed!.

posted Oct 14th, 2014 3:22 pm



Tried this for a week and was not impressed at all. Even after just a week I was so grossed out by the sweetness of the products you have to stick within. And I'm not even a diabetic

The meal bars were like eating a chocolate bar, the snack bars are like chocolate bars too. Then when you come to meal time your so sweetened out you feel sick you can't even eat or you eat too much trying to get the sweetness out of your mouth.

The shakes are alright by themselves, Definitely try adding fruit of any kind, makes them a little easier.

But each to their own... I kinda benefited trying this though. Got so sweetened out that I'm not wanting anything to do with anything sweet for quite awhile!

posted Sep 23rd, 2013 7:42 pm



What would you guys think about doing Slim fast 321 while taking Garcinia Combogia weight l Garcinia Combogia and slim fast 321, yay or ney?

posted Aug 10th, 2013 11:21 am

Leopard Print Addict


Up to how much weight could I lose in a month? I'm 23 years old, and I'm 5 ft. 4. I've never been this big. I weigh 153 lbs. It's really messing with my social life because now I don't feel so social. I don't like to go out. I worry people might be shocked when they see me being that I've always been thin. The biggest anyone had ever seen me was 129 lbs. I am now 24 pounds above that. I'm on day 3 of the 321 plan. I'm extremely dedicated. I'm exercising daily and plan to at least an hour a day, 7 days a week. I'm following the 321 plan as I should. I'm taking mega t green tea, and peach and fiber Omni life drink.

posted Feb 20th, 2013 10:08 pm


Everything I've tried taste good. I feel sufficiently full, not bloated, just full. Started working out 3 weeks into it and its fine too. Been doing it a month now. Used it to lose weight many years ago but now so many more options makes it more fun. Love the meal bars and snack bars plus choc, van & straw ready made shakes. Can't wait to try the chips type snacks.

posted Jan 27th, 2013 8:26 am



love it. Ive lost over 30lbs from this diet. will continue to use.

posted Jul 15th, 2012 12:07 pm



Does my diet plan sound reasonable ? So far day one - just spent a blinking hour drinking one for breakfast, as it made me feel full - it didn't taste awful either. (I'm usually hungry within 2 hours of eating breakfast) I've been meaning to diet for some time, as I put on weight since last summer for various reasons - making me the heaviest I have ever been, but my eating habits were better and I wasn't drinking as much, etc, and I've never tried to lose weight before - I've always been active, now probably not so. I am eating more fruit and calorie controlling through my fitness pal app, and instead of limiting myself to the calories on slimfast, will eat right, and to the calories on my fitness pal that are designed to make me reach my goal over a matter of time .. having a slim fast for breakfast, and for lunch if I'm at home, but a reasonable pack lunch if I am out. I do not count any exercise on my fitness pal app, against my calorie count, as I feel I would be naturally doing this exercise with my previous lifestyle. I'm 23, 5'5", and just over 12 stone, I wish to be 10 and a half ideally, but 11 / 11.5 would be GREAT for now - all my friends say I look like a 12/14, but I've just pushed over a 16, yet I'm still parachute pants in 18's. All I'm trying to do is get back to my once fairly athletic figure, fit in my old clothes and not drown my small waist !! Does this sound a sensible, and diet effective way to do things ?

posted Jun 25th, 2012 10:25 am



To be honest yes it is terrible to only drink or eat slim fast products, but this is not the message they are giving out to people. If you do read more into the 321 diet, it tells you what to eat on a daily basis along with the slim fast products to help you loose weight. So those who are being negative, this diet includes actually healthy food as well as well balanced meals. Those taking only the shakes and bars are doing it wrong. But it's their body, no right to judge.

It works fantastic and I'm healthy says my doctor. Just make sure you are taking this diet correctly. There is nothing wrong with it. Just speak to a doctor before starting any diet, your health is important too.

posted Feb 7th, 2012 8:56 pm



Does the slim fast 123 plan work for smaller people? I'm a 5'2 female who weighs 105lbs, my goal is 95. Does the Slim Fast 123 Plan work for people who only want to lose a little weight? Or only if your big?

posted Jan 2nd, 2012 12:20 am


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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.

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  • 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

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