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Slim Fast Shakes Review

Not Recommended
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Slim Fast Shakes Review

The Slim Fast diet is known worldwide. You’ve probably seen their products in health food stores up and down the country, in this Slim Fast Shakes review we’re look at whether these shakes are genuinely good for weight loss.

Let’s take a look at the top level pros and cons of this product:

Slim Fast Shakes Benefits:

  • Very affordable product
  • Low in calories
Slim Fast Shakes Drawbacks:

  • Nothing ground-breaking about the formula
  • Powdered shakes may not be as tasty as the pre-made version
  • Is basically just a protein shake with added carbs and vitamins
  • No proven weight loss ingredients inside the formula
  • Essentially puts users on a starvation diet
  • May not suppress appetite for very long
  • No money-back guarantee

Slim Fast Shakes Review
Not Recommended

Editor’s Note: Shopping around? Click here to find out our top recommended weight loss shake product.

Some Quick Information On This Product & Company

You probably don’t need us to tell you that Slim Fast shakes are some of the most popular weight loss shakes on the planet! It seems like there are countless high-profile individuals going on and on about how these little ‘miracle milkshakes’ changed their lives and helped them lose a whole bunch of weight in seemingly no time at all. Can the Slim Fast shakes work just as well for the average Joe and plain Jane? Well, we’re here to drop a few truth bombs and enlighten you on just exactly what these shakes are and how exactly they help you lose weight, because frankly these shakes aren’t a miracle cure to obesity as it would be easy to believe.

Let’s begin, Slim Fast shakes… are just milkshakes with added vitamins. That’s it. Nothing else. Is your mind blown yet? You’ll probably also be surprised to learn that the formula doesn’t contain anything to boost metabolism, burn fat or suppress appetite (unlike our top rated weight loss shake does).

The only thing these shakes have going for them is that they are a convenient way to consume less calories per day – as users just need to remember to drink three per day and absolutely not eat in-between them.

The overall concept for the Slim Fast shakes isn’t a complicated one; you simply commit to drinking three Slim Fast shakes per day in place of your breakfast, lunch and dinner in order to significantly lower your daily calorie intake. Users who stick to these directions are technically on a VLCD (very low calorie diet), which is also known as – shock horror – a starvation diet.

Are Slim Fast Shakes A Good Product To Help Me Lose Weight?

Guess what happens when your body goes into starvation mode? You metabolism grinds to a screeching halt and the rate in which you lose body fat plummets as your body is trying to preserve as much fat as possible. You may be surprised to find out that our bodies are naturally programmed to do this. While using the Slim Fast Shakes, you’ll probably find you’re locked in a never-ending battle against hunger – we’ve seen reviews online of people stating this exact point.

It doesn’t take a genius to work out that if you starve yourself some of the weight will come off, but users will probably find that most of it is water weight, and that any fat lost will probably come back once you return to consuming solid food again (any you will go back to solid food eventually, because who the heck wants to drink three bland shakes for the rest of their life?!).

Our Slim Fast Shakes review team have stated that users who discontinue usage of Slim Fast may find themselves trapped into a weight cycle (Yo-Yo effect), constantly losing and re-gaining the same 10 lbs over and over again. You’re up a dress size, you’re down a stress.. rinse and repeat.

For these above reasons we do not think that Slim Fast shakes are the key to long term weight loss success.

What Are The Slim Fast Shake Ingredients?

We have found the following information from the Superdrug website:

Skimmed Milk Powder , Sugar , Maltodextrin , Fructose , Corn Oil , Inulin , Thickeners (Acacia Gum, Xanthan Gum) , Lactose , Bulking Agent (Cellulose) , Milk Proteins , Stabilisers (Sodium Carboxymethyl Cellulose, Potassium Phosphate, Calcium Phosphate) , Flavour , Colour (Beta-Carotene) , Emulsifier (Soya Lecithin) , Vitamins and Minerals1 , Antioxidants (Tocopherol-Rich Extract) , Sodium Ascorbate , 1Vitamins and Minerals: Magnesium Oxide, Ferric Pyrophosphate, Vitamin C, Zinc Gluconate, Vitamin E, Niacin, Vitamin A, Copper Gluconate, Manganese Sulphate, Sodium Selenite, Vitamin D, Folic Acid, Vitamin B6, Thiamin, Riboflavin, Biotin

Looking at these ingredients, we can see the main ingredient is Skimmed Milk Powder, followed by sugar and maltodextrin (carbohydrates). It seems to us that Slim Fast shakes are just well-branded Skimmed Milk Protein Powder. There are no ground-breaking weight loss ingredients used inside Slim Fast Shakes, nor are there any metabolism boosting or appetite suppressing ingredients inside this product.

What Are Slim Fast Side Effects?

The potential side effects to Slim Fast Shakes are as follows:

increased bowel movements, nausea, thirst, bloating, cramps, tiredness (fatigue), and headache. [1]

Note: These side effects are possible but may not be typical.

What Is The Difference Between Slim Fast Shakes and Slim Fast Vitality?

There isn’t too much difference between these two products really. Vitality has additional extras like green tea and whey protein added, but fundamentally they’re quite similar. Think of Vitality as Slim Fast’s answer to the more advanced weight loss shakes on the market. Frankly, we wouldn’t really recommend either of them.

What do Slim Fast Shakes claim to do?

Interestingly, Slim Fast don’t really make any claims about their product – they do not promise any weight loss results at all (despite what their company name may suggest). They literally just refer to their shakes as “high protein meal replacements”. We assume this is because if users do not lose weight, they cannot be called out on false advertising.

Are There Any Reviews From Customers?

We have found the following Slim Fast Shakes review testimonials:

Flavour: Chunky Chocolate | Verified Purchase
dont like the taste.. its weird chocolatey taste

Flavour: Blissful Banana | Verified Purchase
I didn’t realise until I read the label that it is sweetened with artificial sweetener – sucralose. There is enough published research to show that you do not lose weight with artificial sweeteners. I will not be using the other 3 packages. Otherwise it’s good value for money.

Flavour: Simply Vanilla
Having used slimfast replacement meals a few years ago with great success,and always looking forward to my Belgian chocolate/ caramel temptation/ vanilla shakes ect. every morning and lunchtime, I decided to try and loose a few accumulated pounds by the same method. What a dissapointment!!! the formula must have been drastically changed?! Especially the Chocolate and Vanilla, they are tasteless now with a “sort of aftertaste”, which I could cope with if the old flavours were back.

It’s important to seek independent Slim Fast Shakes reviews, rather than believing what’s written on the manufacturers website. We recommend anyone who’s potentially interested in buying these products to do their own research to make up their own mind.

Where Can I Buy This Product?

Slim Fast Shakes are available in most high street food stores as well as online via multiple retailers.

Review Conclusion.

To conclude our Slim Fast Shakes review, we do not recommend this product. It’s all flash and no substance – we believe it’s promoting an unhealthy dietary lifestyle thats impossible to stick to. It also does not contain any fat burning or appetite suppressing ingredients.

I mean, do you really want to be that guy/girl at the bar with a glass of water? Or having to awkwardly explain to everyone why you’re not having a piece of your own child’s birthday cake?! I’m sure that’ll build some golden memories right?

If you’re looking for a great weight loss shake, we recommend you check out our top rated product, Burner Shake.

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Katharine Ross, PhD
Katharine Ross, PhD
Health Editor
Kath holds a PhD in Nutritional Sciences and is the editor-in-chief here at She has analyzed and reviewed thousands of different products in the supplement industry and loves helping our readers find the perfect supplement!