Updated: 02/02/2016 - Sponsored by Leptigen

OptiSlim Review - Does This Diet System Actually Work? Are unpleasant taste and side effects deal breakers?

Editor's Review: 2.8 / 5.0

optislim-product-imageThis review is what happened after I obsessed for weeks over Optislim. We decided to dig deep, examining the ingredients, side effects, scientific research and level of customer care. Plus we sorted through all kinds of user comments and dieter reviews from the internet. Finally, we then summed up all the data and responses we found to give you the info you need.

EDITOR'S TIP: Combine OptiSlim with a proven fat burner such as Leptigen for better results.

What You Need To Know

Optislim is an Australian weight loss program that was originally developed to help morbidly obese patients with weight reduction. This VLCD (very low calorie diet) incorporates total meal replacement and the meals are claimed to taste good and be affordable. An LCD (low calorie diet) program is also available, and it involves partial meal replacement. The food products involved with Optislim include the following; cookies, bars, soups, shakes and main course dishes like beef stroganoff and chili con carne. These products can all be purchased via the main website. There are now four different types of Optislim programs, and these are weight loss, detoxing, toning and weight management.

From what we gathered, Optislim has been around since 1996. There are some success stories posted on the company website and a decent variety of low-calorie foods and supplements are available, but read on…

Unpleasant Taste –A Concern?

According to our Research Editor, “Unfortunately we found all sorts of negative customer reviews pertaining to the Optislim food and supplements. This is a major drawback because if you can’t stomach the diet foods/supplements involved, you probably can’t commit to the diet.”

One customer said, “Most disgusting product and a company with no refunds on unused stock. A waste of money and food is DISGUSTING!”

“These shakes taste really awful. No Thanks!,” said another dieter.

Scroll below for one of the best products we’ve seen over the last year.

Side Effects – Another Drawback

Some people have experienced side effects from the Optislim supplements. One customer commented, “My husband has been using Optislim and has been vomiting and dizzy.”

Another user stated, “When I stopped drinking it my headaches had gone. I went back on the shakes a month later and my headaches returned!!!”

The intensive research we’ve conducted has shown if there is a specific aspect of a diet program or supplement that is quite burdensome (too many side effects, unpleasant taste, a painful exercise) the odds of real fat loss success are not good. In other words, if Optislim does in fact lead to adverse effects in a lot of people, this could be a real dilemma.

The Science – Any?

We were unable to find any solid science provided on the official Optislim website. While we know that seriously reducing your daily caloric intake will lead to weight reduction, you can also accomplish this without the Optislim program. At DietSpotlight, we need to see published clinical research that supports the weight loss product or program.

The Bottom Line: Does Optislim Work?

So, should you invest in Optislim for weight loss? Well, we like Optislim’s longevity as a diet program and some positive comments we saw about it online. However, we have some reservations about it because it’s not backed by science. Moreover, we’re concerned about the unpleasant taste of the supplements and the side effects they can cause.

If you’d like to drop more weight, then we advise you to go with a diet program or weight loss product that is backed by solid science, does not cause unpleasant side effects and is easy to use.

Among the best products we’ve seen in 2015 is one called Leptigen. Its unique formula is a blend of four ingredients, which have been proven in published scientific studies to kick-start metabolism and encourage more fat loss. We can’t find any complaints of harmful adverse effects and customer feedback around the web shows people are seeing solid results.

Furthermore, the makers of Leptigen are so confident in their product they’re offering a Special Trial Offer, which is a positive sign.

Learn More About Leptigen »
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How Does OptiSlim Compare?

Previous OptiSlim Review (Updated January 1, 1970):

What You Should Know

Click Here To See Our Highest Rated Review

OptiSlim VLCD is a very low calorie diet system that replaces meals under the recommendations of a health professional. Within the diet industry, VLCD's are viewed as "extreme" weight loss options, and are usually carried out under a doctor's supervision. The shakes provided will allow a dieter to maintain his or her daily nutritional requirements and lose weight at the same time. OptiSlim Soups contain 25 vitamins and minerals. However, when under this diet arrangement, it is important to maintain fluid intake during the day. The recommended amount is about 2 liters per day.


The ingredients will vary based upon the product used.

Product Features

OptiSlim is a very low calorie diet containing 3350kJ, which amounts to 800 calories or less per day. There are about four products from OptiSlim. These are VLCD Shakes, VLCD Soups, MAX Tablets and OptiSlim Shakers. OptiSlim Soups have seven sachets per pack that come in flavors of tomato, pumpkin and chicken. The OptiSlim Shakes come in milkshake taste and in three flavors Vanilla, chocolate and Espresso Coffee. They contain minerals, vitamins, and trace elements that come in balanced levels. OptiSlim tablets also come with the right and balanced amounts of vitamins and minerals. However, it is still advisable for someone under the OptiSlim program to ensure that he or she has a daily consumption of fibers, low starch vegetables like broccoli, mushrooms, lettuce, spinach, green beans or cucumbers.

People with diabetes, liver disease, gall bladder disease, kidney problems or cardiovascular diseases should first consult a doctor before starting on any VLCD regimen. This is because the program will usually affect the body's metabolism processes and may cause an individual to experience significant physical changes like weight loss. This may affect existing medical conditions. Thus, regular checkups and monitoring by a physician is required to manage these medical complications.

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  • OptiSlim has been shown to reduce the chances of one being overweight and obese.
  • Obesity has numerous complications that include high blood pressure, cardiovascular problems and other forms of cancer. Thus, one reduces the chances of getting these diseases.


  • The use of OptiSlim causes a person to experience some unpleasant reactions including headaches, dizziness, constipation, bad breath, nausea and diarrhea.
  • Following the VLCD program will also cause a person to have an increased amount of uric acid in the body which may lead to the development of acute gout. Acute gout is very irritating and will usually require a doctor's assessment to reduce the discomfort.
  • A VLCD should only be followed under the strict care of a physician.


With only 800 calories or less in a day intake, OptiSlim VLCD programs are clearly one of the most effective weight loss programs on the market when followed under the care of a doctor. The backing of clinical trials on these products is evidence of their safety and effectiveness, but this safety is not something that should be determined by the individual. In order to lose weight effectively without a dangerously low amount of calories, we recommend a fat burner or other weight loss supplement and a healthy diet and exercise.

34 User Reviews About OptiSlim

Leave comments below
  • 1
    Penny Cottee

    I have just started Optisilm approximately how long will it take for Ketosis to start??


    Your Name

    2 days


  • 2

    One more question
    At what time i eat this tablet means after meal or before meal


  • 3

    I m from india and from today itself i started optislim tablets
    My weight is inbetween 75 to 80kg and my height is 153 so pls let me know to refer my height how many kg i loss
    Also in a week what is ratio to loss the weight to using this tablet


  • 4
    kevin forrest

    is optislim approved by australian nutritionist or diet association


  • 5
    Your Name

    Most disgusting product and a company with no refunds on unused stock a waste of money and food DISGUSTING!


  • 6
    Rachael Nolan

    Hi i found out the shakes contain caffeine. Can you tell me how many mg of caffeine per serve? I might still be able to take them if its not too high..


  • 7
    Rachael Nolan

    Do optislim products contain any caffeine? I am very sensitive to caffeine and suffer severe withdrawal symptoms that require medical supervision if i ingest a lot of caffeine and then stop. I also suffer heart palpitations if I take fat burner tablets that utilise caffeine.


    Your Name

    no they don’t


  • 8
    halina flak

    Just recievef my order and was told I was not able to take this products ad I have kidney failure and was told by drs and chemist that im unable to have the product could anyone please get back to me so I can send this back


  • 9

    My 16 year old daughter wants to try optislim, is it safe for her, she is not fat just wants to lost a little off her stomach



    she just needs some tummy exercise not vlcd !


  • 10

    I’ve been on Optislim for almost four weeks, finding is easy, slowly losing 1kg per week. Headache the first two days but increased water intake, feeling great and never hungry like when on other diets. I have shake for breakfast and lunch, small meal for dinner. I can’t exercise. Still enjoying coffee & tea on low fat milk, no sugar or sweetener.


  • 11
    Maureen Prien

    Just started and it tastes great but im a diabetic and wondering what the GI of this product is as my sugars seem a little higher.



    i tried the opti slim shakes my blood levels were very high and i felt very unwell and my eyes went funny i am on insulin at night



    I’m a type 2 diabetic and take Diabex. I’m due to have surgery later this year and need to lose weight, I’m using Optislim on the advice of my dietician and my blood levels have been really good, I feel great and have no side effects whatsoever.


  • 12

    Hi is it possible to use the shakes and tablets together?


  • 13

    Husband using Optislim been vomiting and dizzy



    I’ve been drinking the shake for years, it tastes good but I’ve had terrible headaches. When I stopped drinking it my headaches had gone, I went back on it a month later my headaches returned !!!
    I can’t find out if it contains, Aspartame coke contains Aspartame be aware this product could be very dangerous. I won’t be buying it or drinking it again.



    Your headaches are caused by going into ketosis you just need to drink more water and should pass after a few days!



    Iv just started talking it doctors orders as im struggling to lose my baby weight..iv been vomiting and really bad heart burn and feeling sick and no energy I hope it passes


  • 14

    I’m about to have a gastric sleeve op in less than 2 weeks, most other patients are on Optifast but I am on Optislim, does Optislim reduce the size of the liver the same way Optifast does??


  • 15

    Whear i will buy in uae


  • 16

    hi i have just started optislim lcd today how much wight should i lose a week (average)


  • 17

    Hi How long that you can take it? i have been take optislim for 2 years on and off.
    Thank you


  • 18
    Elaine stevens

    Where can I get the Optislim recepie Book in Queensland I can’t seem to be able to get it anywhere.


  • 19

    can I purchase optislim in Dubai?


  • 20
    patricia armstrong

    where can i purchase optislim max tablets.thank you


    Optislim Customer Care

    Hi Patricia.
    Optislim MAX tablets are available at My Chemist and Chemist Warehouse stores throughout Australia as well as Discount Drug Stores, Pharmacy Select Stores, Blooms The Chemist.
    Kind Regards,
    Optislim Customer Care



    can i have this with soy or rice milk instead of water i am not fat just wanna get rid of a kilo or 2??? I work out and run twice a day so will maybe just replace my evening meal and the odd lunch. always have a healthy breaky!!


  • 21

    Are optifast and optislim one and the same company?


    Optislim Customer Care

    Hi Millie.
    Optislim is a wholly owned Australian company and it’s products are manufactured in Australia. Optifast is owned by Nestle and their products are made in Germany.
    Kind Regards,
    Optislim Customer Care


  • 22

    Does theOptiSlim shake contain any fibre? and if not, why not?



    Yes, you’ll find that it will contain inulin, a fibre that promotes bowl movements. Some people will experience runny stools as a result but I think they’d be in the minority, shakes tend to bind you up so the inulin counteracts that a bit.


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