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Slim Fast 321

Slim Fast 321

Slim down on this easy and flexible weight loss plan.

Top Rated Diet Shakes of 2016
BACKGROUND 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 Shakes of 2016?

  • 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 Misspellings

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

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(Page 1 of 2, 39 total comments)



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

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


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