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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.

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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 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?
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(Page 2 of 3, 44 total comments)

dalia ann garza


How much weight can I lose in 6 weeks on Slim Fast 321? Hello my name is dalia ann garza. And I weight about 220 lbs. when i start my slim fast 321 diet.I want my weight goal to loose 95 lbs in about 4 weeks. how much i can i loose in 4 weeks....?

posted Dec 31st, 2011 3:05 am



More like LOVE THIS PLAN! im a 22 year old girl who has always struggled with losing weight and i finally decided it was time for change! i turned to slim fast 321 and instantly began losing weight! its been around a month and have lost 30 pounds! i work out every night but one and it can range between 30 min. to 60 min.! i am full of energy and life again! and if the scale didnt prove me right my pants sure did when they fell right off! i drink the slimfast shakes for breakfast any 100 calorie snack a meal bar for lunch another 100 calorie snack any 500 calorie dinner and another 100 calorie snack! im never hungry and i feel wonderful! i have recommended this to everyone i know!

posted Nov 19th, 2011 3:35 pm



I lost 5lbs in the first 7 days. You're not suppose to lose more than 2 - but i contribute more of the weight loss to cutting out soda/pop and drinking water to where i felt i was drowning. However; After slowing down on the diet the 2nd week; i still kept off the 5 lbs that i lost. Im back into the diet on my 3rd day so far and I have lost an additional 1lb of weight. I used to be a thin athletic young man at the age of 21, im now 25; i used to take zyprexa for anxiety. It made me go from 140lbs to 244lbs in 4 years. so 104lbs in those 4 years. I am now down to 195 and am so glad the 3-2-1 slim fast plan does what it says to do! Losing that much weight, i feel so much more confident in myself, its made me want to stick to my diet to reach my goal weight of 150 as i plan on turning 5 or 10 lbs into muscle. My metabolism is naturally high, i can eat all the fast food i want and do not gain, the weight i gained was caused by a condition the medication created. No longer on the medication i am shedding the pounds with this diet plan. I suggest you try it!!!!

posted Oct 31st, 2011 7:36 am


this is complete bull****, if you even call this a diet, its less than 1200 calories a day, the calorie guideline for people is broad for all sorts of different people depending on how much you weigh,sex, and bodyfat levels. 1200 is basically staving yourself, sure you'll lose weight, but not bodyfat. you want to lose body fat. not water or muscle. this diet is idiotic. You cant lose 1 pound a day, let alone 9 pounds in one day, if you say you are its not fat you're losing. its water weight! do some research before you go and waste your money on this slimfast junk

posted Oct 17th, 2011 11:21 pm



I have only been on the slimfast 3-2-1 plan for 3 days now and have already lost 1 pound. I love this plan. I was going to Medical Weight loss and only lost 4 pounds in 4 months. I was literly starving on there plan. With the 3-2-1 plan I stay full and I dont crave sugar or go to bed hungry. I give slim fast a big thumbs up

posted Sep 26th, 2011 10:04 am

Julian Ferretti


I am on my third day of the 321 plan. I drink only strawberries and cream for breakfast and lunch thenwhatever i can make thats >500 caloties when i get home. i only eat one snack usually between lunch and dinner since i have almost an 8 hour wait time in between.After dinner i do a 30 minute uphill bike ride. So far i have lost 9 pounds in my first two days and possible more when i weigh myself tonight. I like the program so far. Shakes tastes good, not minerally like other brands and snack choices are easy not that everyone makes 100cal snacks.

posted Sep 14th, 2011 1:04 pm



Today is day one for my slim fast 321 plan and I have a tip for those feeling hungry and to boost weight loss results. Eat high fibre snacks! There is no fibre in slim fast and it's a key in weight loss or maintaining. It makes you feel full and you retain less water.

posted Aug 4th, 2011 12:49 pm



Tomorrow 8/4/2011 will be my first day I have all my meals and shakes taped with day one, two etc so I don't get spontanious and reach for a QUICK fix!! I'm very nervious but I'm so motivated that I'm gonna do this.. I have already been walking a 1.5 miles perday on treadmil, I've made a schedule for adding Julian Micheals video in with weight training 3 days a week. I've plan it out for the first time in my life and I going forward and not looking back...

posted Aug 2nd, 2011 4:29 pm


I started on May 11, 2011 and have lost 27 pounds so far. I am now near my weight range again. Am 69 years old and have used weight watchers anytime I was struggling with weight, but now at 69 I couldn't lose until I tried the 3 2 1 plan. I have arthritis in my knees so have stopped walking my daily 3 miles and that's when I turned to slimfast. I now am having much less problem with my knees. I take an aquasize class for 1 hour four times a week, swim 11 laps (worked up from 1 lap!!) 4 times a week, and on the other two days I walk for just a half hour each of the two days. I love the diet--I love chocolate so never get tired of the chocolate royal, I never have the slimfast snacks --instead I eat a salad, or egg whites and tomatoes, or a yogurt, or grapefruit or other fruit--anything reasonable. I decide my meal ahead of time as to when I will have it. If hubby wants to go out to eat that evening then that will be my meal; if I make homemade bread and hunger for it then I have it for my breakfast--5 slices!!!! Most of the time I have my "meal" at lunch time as it fits best for me, but like I said I've had it at breakfast and at dinner from time to time too.I lose every week and average 2 lbs a week. I lost 5 the very first week but mostly it's 2 lbs or even as low as 1 lb once in awhile but I always lose. I love it and could do it forever!!!!!!!!!!!

posted Jul 22nd, 2011 9:15 pm


Today is day 1, so far so good. I'm planning on eating my 500 cal. meal at the lunch time. This way I won't get 2 shake meals in a row, and I can have more time to burn it off.

posted Jun 20th, 2011 2:50 pm



I just started the Slim Fast plan 2 days ago and so far it's been great. Day 1 is always the hardest but day 2 was much better. I've been drinking a ton of water and instead of eating my 500 calorie meal as my last meal of the day I eat it as the second meal that way it has more time to burn off through out my day. So far I've lost 4.5 pounds in 2 days so I'm very satisfied with my results.

posted Jun 20th, 2011 10:05 am


You definitely have to exercise with it but its been one week, and i have lost 1 inch around my waist and 5 lbs. (keep in mind i never exercised and ate whatever i wanted, and i smoked.) I no longer smoke, I eat healthy, exercise for 30 min everyday, and i swear by slim fast 321 plan!

posted May 20th, 2011 12:13 pm

michele Phillips

I love it ....

posted Apr 15th, 2011 1:17 pm



Although working at Subway might help a bit, I've actually lost about 25 pounds since I started this diet last month (Feb. 23rd, 2011)

I just have to say: it's wonderful.
It's easy to stay on, and you can find many meal choices under 500 calories.

Thanks, Slim Fast
You rock!
*thumbs up*

posted Mar 18th, 2011 6:07 pm


i like the diet plan and i am not hungry at all only the first day thank you slim fast you are the one for me

posted Feb 24th, 2011 11:53 am


I have been on this plan for a month and i have been starving! it is so hard to not cheat. i am not impressed at all

posted Feb 21st, 2011 9:37 pm


I went on Slimfast years ago after I gained 30lbs when I quit smoking. I lost 30lbs in 3 months. I found the diet convenient (you just throw your lunch into your bag and go). It can get a bit boring, but by the time that happens your pants are loose and that keeps you going. I'm older now and don't expect the same results I had then (I've got thyroid problems now), but I'm game for trying. WW didn't help me at all and I really stuck to it. Wish me luck!

posted Feb 15th, 2011 11:13 am



i was starving trough the whole diet didnt quite work out for me

posted Jan 3rd, 2011 6:00 pm

Anna Potts


I started the 3-2-1 plan on Friday.. I weighed in Friday morning & weighed 189.8 & this morning (Sunday) I weighed in at 185.4.. That's 4.4 lbs in 2 days!!! & I havent even worked out.. I'm gonna start working out & hopefully lose even more.. This plan works GREAT! I replace breakfast & lunch with a shake .. & for my snacks I eat the 100 calorie packs (so I can get in my sugar & salt cravings without messing up my progress) & dinner I have just been making whatever stays right around 500 calories.. I have also been drinking a LOT of water

posted Dec 12th, 2010 3:21 pm



I started this diet 7 days ago and have lost 6 pounds. No exercise. Lots of water. I am alot over weight so that may be why I lost so much in a week.

posted Sep 16th, 2010 12:07 pm


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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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