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Slim Fast Exposed 2024 [MUST READ] - Does It Really Work?

Want to lose weight but not sure where to start? Here's one of diet convenience mainstays.

Top Rated Diet Shakes of 2024
What is it?

Slim Fast is a meal replacement shake said to be clinically supported to help keep weight off. It’s offered in 4 distinct flavors including creamy chocolate, strawberries & cream, vanilla cream, and caramel latte.

It’s said to help control hunger for a total of 4 hours, and it’s made with 20 grams of protein and just 1 gram of sugar. This ready to drink shake is made without any gluten or lactose, and the company offers it in many retail stores. Is this meal replacement a good option for weight loss? What kinds of effects are customers experiencing? In this full review you’ll see what Slim Fast truly has to offer. Discover the top 10 diet shakes by clicking here.

Do You Know the Best Diet Shakes of 2024?

Slim Fast Ingredients and Side Effects

Here are the ingredients to their creamy chocolate flavor:


Calcium Caseinate

Milk Protein Concentrate

Canola Oil

Cocoa processed with Alkali


Cellulose Gel

Natural and Artificial Flavors

Potassium Phosphate

Mono and Diglycerides


Potassium Citrate


Soy Lecithin



Sodium Citrate

Citric Acid

Caramel Color

Magnesium Phosphate

Sodium Ascorbate

Calcium Phosphate

Vitamin E Acetate

Zinc Gluconate

Ferric Orthophosphate


Calcium Pantothenate

Manganese Sulfate

Vitamin A Palminate

Pyridoxine Hydrochloride

Thiamin Mononitrate


Chromium Chloride

Folic Acid


Sodium Molybdate

Potassium Iodide


Sodium Selenite


Sweetened with non- nutritive sweetener


Milk Protein Concentrate:  A processed form of milk protein that loses its minerals and liquid. It’s spray dried and treated as a cheap and longer lasting alternative to regular milk. 

This ingredient has been used controversially, since around 70% of it is imported from countries with different safety standards.

The Food and Water Watch group has released a statement on this ingredients lack of safety:

“MPC’S are largely unregulated”

There are concerns of this ingredient being contaminated with melamine. This ingredient is considered harmful if swallowed, and it’s also known to irritate the skin.

It's believed that pasteurization is able to kill contaminants; this is why the FDA allows this ingredient to be imported in. Though the Food and Water Watch Group argues this isn’t enough, and that things like melamine are still found and cannot be pasteurized away.

Potassium Phosphate: Typically given as a medication to help balance out the amount of calcium that’s in the body. It makes urine more acidic and is used to help prevent kidney stones.

Possible side effects may include:

  •  Headaches and dizziness.
  •  Nausea and vomiting.
  •  Diarrhea.

Sucralose: A non-caloric artificial sweetener that is up to 1,000 times sweeter than average sucrose.

The Journal of Toxicology and Environmental Health did a study on rats. They found many damaging effects including:

“increased fecal pH and enhanced the expression of P-gp”

“exerted numerous adverse effects, including reduction in beneficial microflora”

Damaged microflora can have serious health consequences, such as reduced immune function and increased inflammation. It’s also known to cause symptoms of depression.

P-gp or glycoprotein is a found in the cells membrane, and it makes sure that any potential contaminants are filtered out of the body. So according to this study, sucralose is considered a toxic ingredient when in the body.

Carrageenan: Thickener and binder found in red seaweed.

A study on mice showed that this ingredient could cause tumors. The Cancer Letters published a clinical study that showed major damage:

“degraded carrageenan is carcinogenic to the colorectum of the rat”

This effect was seen in just small doses of this ingredient.

Artificial Flavors: A man made synthetic ingredient used to mimic the taste of real flavors. It can be made from many different foods and it’s unknown where Slim Fast sources their ingredient from.

This ingredient is a cheaper alternative to more wholesome and real additives.

Caramel Color: A food coloring made from treated carbohydrates.

It can be extracted from many common allergens, though it’s unknown where Slim Fast sources this ingredient from.

This is a highly processed ingredient that is specially treated in order to provide a color to drinks.

Slim Fast Quality Of Ingredients

When judging a meal replacement shakes, it’s important to look at the quality of the sweeteners and protein. The protein added to Slim Fast comes from cheap sources in milk protein concentrate and calcium caseinate.

Milk protein concentrate in particular has been shown to be heavily processed and potentially contaminated.

The added sweeteners sucralose and a nonnutritive sweetener which is never explained are also added. Though sucralose provides just 1 gram of sugar to this mixture, it’s been shown in studies to cause tumors. It also is treated as a toxin within the body, according to respected clinical studies.

There’s also a total of 180 calories added, which is exceptionally higher than other meal replacements. When looking to lose weight, it’s important to keep calories as low as possible in order to prevent weight gain.

Overall, the quality of ingredients is poor. There are artificial flavors, artificial sweeteners, and cheap protein added. In this top 10 list are the very best meal replacements.

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

The Price and Quality of Slim Fast

No official price is set by the manufacturers, but they do offer an interactive map showing the approved vendors.

An 8 pack of their chocolate sells for $14.16 on their Amazon.com page.

Since each shake is a full serving, around a month’s supply or a 32 day serving would be $113.28, if taken twice a day.

This is expensive for what are a cheap protein, and a blend of artificial ingredients. Though the sugar is low and the protein and fiber is high, it’s important to look at the ingredients to help determine the overall quality.

Too many artificial ingredients are added to suggest this would be a good brand to replace a meal.

There’s also no listing of the amino acid profile, so it’s unknown how well rounded the protein is. Amino acids are important since they provide support for many important body functions.

The company makes suggestions that up to 4 hours of appetite suppression are possible. They fail to offer any proof of these claims. It’s unknown if this is backed by any real studies, or it it’s a suggested number.

There was an issue with contamination in the past. The Associated Press reports:

“recalled all canned Slim Fast drinks because of the possibility of bacterial contamination”

“could cause diarrhea, nausea, and vomiting”

This 2024 recall was approved for all cans of Slim Fast, and it’s unknown exactly how this contamination was started. The manufacturers failed to provide any evidence that this issue wouldn’t happen again.

Business of Slim Fast

Information on the company practices aren’t explained on the official website.

The company name is also called Slim Fast. Here is their listed contact information:

Phone Number: (800) 754-6327

There are currently a total of 39 negative reviews against the company on their Consumer Affairs listing. This is due to their changed formula which sells for more but it’s offered in smaller portions. Also, people were disappointed with the lack of customer support.

EDITOR’S TIP: For the best results with meal replacement shakes diet our experts recommend to use it at least 5 months. Save your money buying a few bags of meal replacement product.

Customer Opinions of Slim Fast

Many reviews are available online, here’s what a few customers have had to say:

“my stomach began to get bigger”

“seems like it put weight on me”

“tastes like your generic, low-calorie protein shale”

“didn’t find this had the “four hour hunger control” it claims to have”

People mentioned how the taste was terribly artificial, and that it was hard to drink each bottle.

Weight loss was also missing for some customers, while others added how they actually gained weight even with diet and exercise.

Some side effects were also listed including nausea and ill feelings.

Appetite suppression was also lacking. For many customers, there was a lack of any benefits in drinking these shakes.  The best options for weight loss are found in this top 10 list of meal replacements.

Conclusion - Does Slim Fast Work?

When making a decision on Slim Fast, it’s important to look past the supplements facts label. Though this shake does have a high amount of protein and fiber, as well as low sugar and lots of vitamins and minerals, it’s what’s truly inside what counts.

This shake has a combination of artificial sweeteners, artificial flavors, and a high amount of calories which might make weight loss harder. That’s why so many customers have mentioned that they not only failed to lose weight, but some actually increased in size.

This shake also uses a cheap protein source, with ingredients like sucralose which have been shown to cause tumors in clinical studies. Much better solutions exists which are made only with all natural and wholesome ingredients.

The very best meal replacement of 2024 offering all the necessary criteria for weight loss is 18Shake. This meal replacement has a high quality mixture of whey protein which is easy to digest, and well balanced in amino acids. It’s also made with a high amount of fiber, and low sugar. That’s why so many users have mentioned it’s a great solution for weight loss. You can find these impressive testimonials on their official website.

18Shake  also has no binders, fillers, or artificial ingredients. All you get is a high quality formula made to help suppress appetite and increase weight loss. It’s even backed by a great 30 day money back guarantee. That’s why so many users keep coming back to this comprehensive meal replacement.

How Does Slim-Fast Compare?
  • Product Name
  • User Rating
  • Has Good Appetite Suppressant
  • Has Only Natural Components
  • Good Taste
  • Slim-Fast
  • 27 /100
  • .

> Leave Feedback

User Feedback

(Page 1 of 7, 127 total comments)

Kelly Swain

Works a treat and fits in with my busy lifestyle. Also I have gone off food and find it’s a way of still having something in my tummy

posted Jul 19th, 2018 5:23 pm


My mom after giving birt to my brother started slim fast 2 days later. She drank a slim fast a day while eating small portions of her meals for 2 weeks. In that 2 weeks she went from a size 18 to a size 6

posted Jun 6th, 2018 3:41 pm


I love the SlimFast diet, their website has enough information on it to understand how the diet works. You still get 2000 calories, it's just the shakes make up part of the 2000 calories and so do the snacks you get to eat. The SlimFast website explains that you can have up to 3 snacks a day in-between the shakes and the meal, but only if you get hungry in-between the shakes and your meal. However each snack can only contain 100 calories each and 0g to 1g of sugar each. Most if any sugar intake should come from the SlimFast products. So basically, if you take a calculator and put in 2000 calories and subtract the 200 calories from each shake and 100 calories from each snack, what you have left on your calculator is what you can consume for your meal. Your meals should be sensible. I still eat fruit, which of course has sugar in it, as well. I am down to 1 snack a day. I have lost, so far, a total of 14 lbs in 3 months. I'd have to say it works. I buy the powdered mix, "Rich Chocolate Royale". By the way, I do not use low-fat milk like the directions state, I use whole milk, yes I said whole milk and I'm still able to lose weight. Of course it will taste like crap if you use fat-free milk, fat-free milk tastes disgusting to me and always has! Oh yeah, and I have two cheat days a week, Fridays and Saturdays, also holidays, I won't miss out on feasting on the holidays, thank you very much. You just have to tweak it to your own healthy specifications. Remember the website has everything you need to know. The bottles and the powdered shake canisters only have a tidbit of the information you need to know on the SlimFast diet.

posted Apr 24th, 2018 7:09 pm

Laura Brown

Lost 20# over a four month period.

posted Apr 22nd, 2018 1:20 am


Love it
Lost 20lbs

posted Apr 10th, 2018 7:28 am

Connie mason

I lost 50 pounds in 4 months drinking slim fast and eating peanut butter that's been 6 months ago I'm still keeping the weight off and I am so healthy. Thank you slim fast

posted Feb 26th, 2018 9:01 am

kelly williams

My mother lived on slim fast for atleast 20 years. It was very rare for her to ever eat anything solid. Now she is 70 lbs and white as a ghost and deteriorating very rapidly. She lived on slim fast and diet coke. stay away from both of them. eat real food and drink water. check the ingredients list instead of the macro nutrient list if you are serious about your health

posted Feb 13th, 2018 8:00 am

Dawna May

Yummy shakes. I have one in the evening to keep me away from ice-cream!

posted Jan 23rd, 2018 2:05 pm


Why do the meal replacement bars have half the sugar then the shakes do!!! Slim Fast Diet

posted Jan 12th, 2016 9:45 pm


I have been exercising at least 30 mins a day for abou a week and decided I would like to cut down on my food and start a diet. The slim fast was recommended a lot by people that I know and just by exercising a week I have lost 6 pounds! Doesn't show at all but it does make a massive difference in the end. Today is my first day of slim fast and so far I love it. I continue to use this diet and exercise regularly everyday to push myself abit more. Would recommend exercising as it helps lose more

posted Sep 10th, 2015 1:14 pm



I tried the Slim Fast diet for about a month and lost about three pounds. The shakes are delicious, but I didn't enjoy drinking them. It became monotonous. The meal bars were disgusting, eating candy bars constantly. The diet felt unhealthy, with all the chocolate and sugar. I was hungry a lot, too, especially in the evening after my "sensible dinner". I have containers of Slim Fast from this diet, partially used. My daughter enjoyed putting them with whole milk and microwaving it.

posted Mar 7th, 2014 6:52 pm



I just mixed the vanilla shake mix with 1 cup of skim milk, 1/2 cup pf canned pumpkin (40 calories!) and 1/2 tsp pumpkin pie seasoning. Yummy, like pumpkin pie in a glass!

posted May 30th, 2013 11:05 pm



I started on 2-22-12 and I've already lost 5 lbs :-) Somedays I feel hungrey but I just drink water... It really works and I dont even exercise!

posted Mar 3rd, 2012 3:28 pm


I love Slim Fast! I don't follow the whole program for a couple of reasons: first I get really hungry in the morning so I need take some of the calories allowed in a day and have them at breakfast. Second, I live alone so making the dinners they recommened would result in too many servings for me. This is how I made the plan work for me: the night before I'd take one of those reusable iced coffee cups from Starbucks and I'd add a cup of milk, a scoop of Vanilla SF powder, a spoonful of instant coffee and some water. Every week or two I'd fill one of those 8 cup Glad containers with berries (frozen or fresh), then I'd make up some jello and with one envelope of Knox and add it to the berries and refrigerate. The gelatine protects the berries from air and (I have found) makes them last longer in ready to eat form. You get some sugar or sweetner in the jello, but it's not much. So, for breakfast I'd have a just over half a cup of the berry gelitine salad, and a serving of whole grains like toast or oatmeal. Then I'd grab my shake and head to work. I sip on the shake all morning whenever I'm hungry. My co-workers get so jealous because it looks like I went to Starbucks. Lunch is a SF bar with an pre-sliced apple and a snack bag of raw veggies, and water. Afternoon snack (if I need it) is any veggies I didn't finish and a maybe a 100 cal granola bar. Dinner is about 350 cal. I'll have a frozen entree or something from a cookbook that says it's 350 cal or less per serving. I also have a big tossed salad with precious little dressing (40 cal or less) and an orange veg if I haven't already had one that day (for vit A). Dessert is a cup of tea with one sugar cube (just 19 cal). Bedtime snack (without it I won't sleep) is about 1/2 cup of super low cal yogurt, 1/3 cup of that very high fiber cereal that looks like rabbit feed, and a banana. Between dinner and snack is work out. I did 20-30 minutes of cardio and weight lifting every other day. That way I was loosing a pound or two a week. It's kind fo expensive but sometimes SF goes on half price at Wal-Mart and I stock up.

posted Jan 14th, 2012 11:50 pm



I like this diet it really works if you stick to it. I am just starting today for the 5th time. it is mind over matter. My friend did this for 3 months and went from a size 14/16 to a size 4 and in weight it was 185-120. The key is join www.slimfast.com it is free and do what it says and DON'T cheat.

posted Aug 25th, 2011 6:32 am


i been on it for two weeks and i have lost 7 lbs. i have 13 more to go. my fav is the creamy chocolate. i have 2 shakes aday... one for bk, wait 2hrs eat a banana , than wait 2hrs and have another shake, than ill have greek yogurt, than for dinner i eat fiber one cereal with almond breeze or 2 boiled eggs with toast or peanut butter sandwich and like an apple.

posted Jul 20th, 2011 12:11 am


l love the Slin Fast 321 diet. l have lo lost 44 pounds in six weeks!!

posted Jun 11th, 2011 4:43 pm



Lost 5 pounds in just one week!
Bikini body in less than two months, here i come! <3

posted Apr 11th, 2011 10:37 am


your GOING to be hungry when you start a healthy eating program for the first couple of days or weeks. Your body is use to you eating all the time, or eating large quantities, so when you don't supply, it will demand. your body just has to learn, it's not gonna get it. your tummy will shrink in a few days or weeks.

posted Mar 22nd, 2011 11:00 am



This seems to work for me, but I do the low carb/low sugar variety now that I'm over 40. Also, the amount of aspartame in a shake is the same as that of a diet soda. However, aspartame has recently been taken of the carcinogen list, but if you have PKU, then of course, avoid it. But also, most ADHD and ADD medications have Aspartame in them as well, so I'm kind of dumb-founded as to why there is such a ruckus.

posted Feb 22nd, 2011 11:17 am


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QUICK FACTSQUICK FACTS Start the Diet Now Advertisement
  • Established: 1977
  • Founder: Daniel Abraham
  • Headquarters: Unilever in Unilever House, London
  • Stock Symbol: UL
  • Accessibility: Retailers and drug stores
  • Diet Type: Meal replacement through shakes, bars and snacks
  • Gender: Male, female

Do You Know the Best Diet Shakes of 2024?


Slim-Fast made its name with meal-replacement shakes. But today it has expanded into a complete weight loss plan complete with an array of products and an organized weight loss plan.

By lending convenience and simplicity to its dieters lives, it has grown its product offering to include bars, snacks, smoothies, as well as a meal plan called Slim-Fast Optima, which provides a healthy combination of complex carbs, protein and healthier fats. For those watching their carb intake, there is a low-carb option and a low-sugar option.

The Slim-Fast plan offers 100 percent of the nutrients your body requires and typically has women consuming 1,200 calories daily. Weight loss is supported by the low-caloric intake. The Slim-Fast plan allows you to use both their products and your choice of nutritious foods to promote healthy weight loss.

Slim-Fast outlines a four-step approach to weight loss: Portion control, sensible eating, regular physical activity, and support.

By sticking to the plan, you can lose 10% of your body weight in the first six months at a rate of one to two pounds a week.

  • Convenience of food products for people on the go
  • Variety of flavors to choose from
  • Realize actual weight loss
  • Calorie intake isn't unsafe
  • Named #3 in the Best Commercial Diets by US News, 2011
  • As with all packaged food plans, the cost will be more than if you prepare all of your own meals
  • Contains aspartame

There are a variety of ways to mix-and-match the Slim-Fast foods with your food choices. The Slim-Fast plan involves six small meals/snacks every day. You are advised to use Slim-Fast products for two meals and one snack daily.

The rest of the day, you're on your own to choose healthy meals when eating out or cooking at home. No calorie counting is necessary and no foods are forbidden; you can still eat your favorites. However, lean protein, fruits, and vegetables are emphasized.

Their meal plan might look like this:

  • Breakfast is a Slim-Fast Smoothie with six ounces of fat-free yogurt.

  • Lunch is a Slim-Fast Shake or Bar, in addition to a whole-wheat english muffin topped with marinara and low-fat mozzarella.

  • Dinner will be your one meal with no more than 500 calories. For dinner, divide your plate in fourths- half should be vegetables, one-quarter protein and one-quarter starch, along with a salad or fruit.

While following the Slim-Fast plan, be sure to drink plenty of water and commit to regular exercise.


The Slim-Fast website has a thorough exercise support system that you can customize to your needs and desires.

It is recommended that you exercise 30 minutes a day to receive optimal results.


Slim-Fast is one of the "veterans" in the prepackaged weight loss solution arena. They're popularly known for their meal replacement shakes, but that doesn't mean you are restricted to a liquid diet. Mix and match their products with regularly prepared healthy food, and busy people like you can find healthy weight loss success.

Common MisspellingsCommon Misspellings

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