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Slim Fast Exposed 2023 [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 2023
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 2023?

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 2023 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 2023 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 5 of 7, 127 total comments)


i have been on slim fast now for 2 weeks and have lost 3 " form hips and 2 from waist so im very happy but i am really scared that if i stop the slim fast ill put it all back on, surely the weight can only go back on if you eat junk so i dunno! someone told me you need to basically replace one meal forever to keep the weight off...

posted May 13th, 2008 3:40 pm


Seems like a good diet plan! I think i will try it!

posted May 7th, 2008 9:39 am


I started the Slim Fast plan 3 weeks ago and have lost 8 pounds. The Rich Chocolate Royale shakes are delicious and satisfy my craving for chocolate. I have about 70 lbs. to lose so their website designed a plan for me that includes small amounts of healthy food with my morning and noon shakes. I love the Banana Nut Muffin bars. I tried the Blueberry Muffin bars but they were too dry. I also like the Crispy Peanut Caramel snack bars. They satisfy my craving for Snickers bars. The products I use are from their Optima line. The website has been down for nearly 2 weeks; don't know what the problem is.

posted May 5th, 2008 8:38 am


I have been using the Slim fast shakes for about 5 days to a week now and I am honestly too scared to step on the scale and check my weight, but my pants are bigger on me and I feel better and more sexy than before. So even if I don't loose weight I would like to say that it over all maked you feel better. I usually have one for breakfast, then I will have a snack at lunch and I will drink another one around 2-4pm.

posted May 2nd, 2008 4:14 pm


I miss the orange slim fast drink that you used to make!!!

posted May 1st, 2008 4:42 pm

Fat Girl

I have just started using the products that help control hunger and might I say it taste so AWFUL and GROSS that it actually makes you HATE FOOD! I'll keep using it and try to get a bike cuz I need to loose 100lbs. I'm 220lbs and I'm only 14 I'm fat as hell. ~Note this is not one of the freaking fake testomoanials because I loathe those so I just want everyone to know. My email is [email protected]

posted Apr 30th, 2008 8:46 pm


I tried Sf before, and I had the shake for breakfast and dinner, with my meal at lunch, has anyone tried this method before with success? I am finding it a bit difficult this time around, and wondering if I should try the method of a shake for breakfast and lunch.

posted Apr 30th, 2008 8:46 pm


i lost 40 lbs in 2 weeks on this diet i love it! i was also going to the gym 3 days a week

posted Apr 30th, 2008 8:46 pm


Started two days ago, down 3.2 pounds....liking it so far! They don't taste that bad either, I have tasted far worse!

posted Apr 30th, 2008 8:46 pm


I purchased the SF products and have been using them in conjunction with healthy foods, such as fruits and vegetables and of course the sensible dinner in the evening. What a great product. Convenient and idiot proof! As with any diet or change of eating habit, it still takes committment, mental reprogramming and the desire to change and become healthy. Slim Fast works if you work it! Good luck!

posted Apr 28th, 2008 1:12 pm


i love the chocolate shakes. i just started today and i've already lost 2 lbs!!

posted Apr 28th, 2008 8:31 am


I bought this product yesterday for just trying. It was delicious and full of good ingredients.

posted Apr 28th, 2008 8:31 am


I must say, slim fast is the only thing that has really helped me lose weight. There were times when i got sick of the shakes and wanted to eat real food. i think it helps if you do have a piece of fruit w/ them. it helps crave the chewing sensation that you miss. but it works as long as you follow it correctly.

posted Apr 10th, 2008 5:52 pm


I also have talked with people who would have a shake then eat a meal. thats not how it works thats why they never lost weight. common sense people.

posted Apr 10th, 2008 5:52 pm


I don't understand how people can say that they GAINED weight on Slim Fast. People prob are eating the bars like they're candy bars. The point is to eat the shake as a meal, or eat it with a piece of fruit. I just started this yesterday, and wow, the shake really filled me up. I was surprised. I'm looking to lose about 10-15 lbs. I'm excited to see the results :D

posted Apr 10th, 2008 9:46 am

jean brosseau

Danielle: You should be disappointed in yourself and not the product. You only gained weight when you stopped using the product... So it is you that can't control you eating habits

posted Apr 5th, 2008 3:58 pm


for those of you who are drinking the shakes and using the bars, you have to eat a healthy snack in b/w eat a small side salad or a boiled egg with the shakes.. or else you will be hungry and resort to eating other junk..

posted Mar 31st, 2008 7:31 pm


i think that it might work ill give it a try :)

posted Mar 31st, 2008 11:38 am


I started using slim fast 6 weeks ago and lost 10 pounds. I went from 120 to 110. I get compliments every where I go. The Rich Brownie bars are my fav. I dont care for the shakes, so I have one bar for breakfeast. one for lunch and a sensible dinner. It just irritates my stomach a little bit but its worth it!!

posted Mar 24th, 2008 4:37 pm


I successfully completed the slim fast diet and lost 30 lbs, I thought it was great until a few months later. Because I stopped buying the shakes and meal bars I gained back the 30 lbs plus! I am very disappointed and unsatisfied with this product.

posted Mar 17th, 2008 8:59 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 2023?


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.

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