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Optifast Review: Does it Work?

Program offers 12 weeks of meal replacement to help you lose weight.

Top Rated Diet Shakes of 2017
What is it?

Optifast is a meal replacement shake offering 100% of 24 vitamins and minerals. It’s claimed to be an easy to mix formula, and they also offer a ready to drink liquid shake.

Their powdered shake has a combination of dry milk and calcium caseinate that equals 14 grams of protein. They currently offer three flavors in Strawberry, Chocolate, and French Vanilla. These shakes are meant to be drunk alongside the other meal replacement foods offered by the company. On their own, they’re said to be a nutritionally healthy choice. So are these shakes truly effective for weight loss? What kinds of ingredients are added, and are they wholesome? This Optifast review will help you discover the truth about this meal replacement.  To discover which meal replacements made it to the top 10 list, click here.

Do You Know the Best Diet Shakes of 2017?

Optifast Ingredients and Side Effects

Nonfat Dry Milk


Calcium Caseinate

Canola Oil (BHA/BHT)


Potassium Phosphate

Magnesium Oxide

Mono and Diglycerides

Choline Bitartrate

Potassium Chloride

Ascorbic Acid

Natural and Artificial Flavor

Alpha Tocopheryl Acetate

Ferrous Sulfate

Zinc Sulfate

Vitamin A Palminate


Copper Gluconate

Calcium Pantothenate

Manganese Sulfate

Vitamin D3

Color (Beta Carotene, Turmeric Oleoresin)

Pyridoxine Hydrochloride

Thiamine Hydrochloride


Chromium Chloride

Folic Acid


Potassium Iodide

Sodium Molybdate

Sodium Selenite

Vitamin K1

Vitamin B12



Nonfat Dry Milk: Dehydrated milk that is added to foods due to its naturally long preservation. 

This ingredient is often imported in from difference countries. There’s controversy over its use, due to a 2008 scandal where 300,000 people were contaminated from this ingredient.

It was found to be contaminated with melamine, which is added to help increase the protein content. This could also lead to kidney stones and renal failure.

A recall began in China after several people had debilitating illnesses.

Fructose: Fruit sugar that is absorbed directly into the bloodstream when digested.

It’s considered one of the worst sweeteners that can cause metabolism disorders, as well as raise the risk for obesity. The University of California, Davis performed a clinical study showing:

“increased consumption of fructose may be detrimental in terms of body weight and adiposity and the metabolic indexes”

“shown to induce visceral obesity, insulin-resistant diabetes, and hyperlipidemia”

This means it can cause issues with raising blood sugar, and it can increase the risk for weight gain. These kinds of effects have also shown a rise in obesity related illnesses.

Fructose when it’s extracted from fruits has been shown in many other clinical studies to be harmful to overall health.

Calcium Caseinate: Protein taken from the casein found in milk. It’s a cheap protein source often added to increase the amount of protein in foods.

Though it can lead to a sense of fullness, this ingredient is cheap to make, and isn’t as potent in amino acids as other protein sources.

The manufactures also fail to list the total amino acid profile. So it’s impossible to determine whether it has enough amino acids to help the body’s performance. When replacing meals it’s important to determine how much amino acids are provided, instead of solely looking at the total protein content.

You can discover the best shake brands for weight loss by clicking here.

Canola Oil (BHA/BHT): Oils made from the processed seeds of rapeseed. BHA and BHT are preservatives added to help fats from going rancid. Live Science has mentioned there are possible side effects. They listed studies in which this ingredient lead to:

“cancer in rats, mice and hamsters”

In California this ingredient has also been listed as a carcinogen.

Artificial Flavor: Man made synthetic ingredient used to help make food taste a particular way. It’s often added to help substitute natural flavors that would be harder to keep fresh.

It can be extracted from many different common allergens including soy, wheat, and corn. Though it’s not required for the company to list how they sourced this ingredient from. This could potentially lead to unwanted side effects.

Optifast Quality of Ingredients

Optifast has a total of 18 grams of sugar that comes from fructose, which is considered one of the worst sweeteners available. Multiple studies have shown it to potentially raise the risk for obesity. 18 grams of sugar is a significant amount as well, this can make weight loss harder.

Also, there are preservatives that have shown to potentially be carcinogenic.  Both BHA and BHT have been found in some studies to have a damaging effect that leads to cancer.

There is a high amount of protein at 14 grams, but it comes from cheap sources such as nonfat dry milk and calcium caseinate. Both of these can be purchased for much cheaper, though they’re not the best protein sources. The company also fails to list the total amino acid score, so it’s impossible to determine if the protein provided is well rounded enough.

There’s far too much calories as well at 160 per serving. The combination of high sugar, calories, and no fiber make this a very poor meal replacement shake. It can all make weight gain easier, instead of helping support a weight loss diet plan.  For your convenience, the top 10 meal replacements are available here.

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

The Price and Quality of Optifast

The company fails to mention how much these shakes cost. They only offer sales for people who visit their clinics, and then they try to recruit people into their centers.

It’s important to be able to know how fairly this is priced. Though due to the high amounts of sugar, low quality protein, no explanation as to the amino acid content, and the 0 grams of fiber, this shake isn’t a well-rounded enough meal replacement. It’s unlikely to help people with appetite suppression.

Web MD advises to find a meal replacement that offers the following:

“3-5 grams of fiber per serving”

Without this, you aren’t getting enough fiber to help promote healthy digestion and appetite suppression. Since you aren’t getting enough fiber from this shake, it does not qualify as a proper meal replacement. You’d have to supplement with additional fiber sources to make up for the lack of quality.

Before considering any shake, it’s important to know exactly how much it costs. Since this meal replacement has poor ingredients, it shouldn’t be priced too high.

Business of Optifast

The Nestlé Health Science company makes this brand. They can be found via the following customer support information:

Phone Number: (800) 662-2540

Address: 445 State Street

                   Fremont, Michigan 49412

They fail to mention whether or not they offer money back return. There’s also a problem with controversies.

The company has also had to recall their products in the past due to contaminations.

The New York Times added that

“The Food and Drug Administration … was investigating and working with Nestle to pinpoint the source of the latest E.coli contamination”

This outbreak ended up harming several people, who had to be hospitalized. It’s unknown how this problem was handled to ensure it wouldn’t contaminate any future batches of their foods.

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 Optifast

There aren’t many reviews on the shakes themselves. Here are a few of the limited customer reviews online:

“found I was always hungry”

“first three days were awful”

“struggling a bit”

There was the common opinion that this meal replacement failed to suppress people’s appetite. For many, it was shown to cause extreme hunger and many continued to have constant thoughts about food.

The company also fails to provide any testimonials or studies to show why this shake would be a proper meal replacement. Without much information available, it’s unknown if this is priced fairly, or if customers found it useful for weight loss.

The few reviews have all been negative towards the overall quality of these shakes.  The highest ranking meal replacements are available in this top 10 list.

Conclusion - Does Optifast Work?

When considering a proper meal replacement, it’s important to make sure there’s enough fiber with low amounts of sugar. Optifast has too much sugar added that’s from a sweetener shown in studies to potentially cause weight gain. Better options are available that have no preservatives, high quality protein, and all natural ingredients. Its customers have also reviewed this shake poorly.

When searching for a proper meal replacement, it’s important that customers reviewed it highly, and that it has a well-rounded nutritional profile. There’s simply not enough support for this meal replacement to rank it as one of the best.

The very best shake out of 2016 that offers all the mentioned benefits is 18Shake. There’s 5 grams of fiber, 1 gram of sugar, and just 90 calories added to this all-natural formula. Customers mention it’s great for reducing appetite, and that people have lost significant amounts of weight. Best of all, it’s made only with natural ingredients, and no fillers of any kind.

This meal replacement has many customer testimonials showing just how effective it truly is. People rave about its easy mix formula, its ability to suppress appetite, and how effective it is for weight loss. They also mention that it tastes great, which is important when using a meal replacement so you don’t lose track of your diet.

18Shake is supported by a great 30-day money back guarantee, which you can learn more about by clicking here. So you can use this shake with the knowledge that there’s no risk in giving it a try.  

How Does OPTIFAST Compare?
  • Product Name
  • User Rating
  • Has Good Appetite Suppressant
  • Has Only Natural Components
  • Good Taste
  • 39 /100
  • .

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User Feedback

(Page 7 of 14, 272 total comments)



I was very eager to reduce my weight,but in 3 weeks i not yet reduced one kg why.my brother lost 3 kg in 3 weeks i was very upset.give a idea

posted Apr 13th, 2010 10:34 am



I followed this diet religiously for 30 days and only lost 10 lbs- While that is probably a healthy rate of loss, I have done other diets such as weight watchers and south beach and lost the same amount while continuing to eat normal food. On only 800 calories a day I felt exhausted and almost fainted at work. My roommate said I was "like a ghost" and my personality disappeared because I had no energy. I have since gained back all of the weight I lost plus more. While on the diet I learned that 800 was chosen as the allotted amount of calories because anything less than that is technically starvation. Even Guantanamo Bay prisoners are required to get over 900 calories a day. This diet made me feel awful, was very expensive, and did not provide lasting results. I do not recommend it.

posted Apr 1st, 2010 7:04 pm


Hi, I'm on Day 2. Day 1 wasn't too hard. My doctor allows me 1/3 cup of Fiber One cereal and unlimited (non starch)vegetables. The Fiber One was an important snack last night at my typical munchie time. So far I've drunk a blender vanilla shake, a chocolate bar and two prepared chocolate shakes. They taste good. Very thankful for the bars.

posted Mar 28th, 2010 2:47 pm



i have been on optifast for three weeks and lost 17 pounds. i am never hungry and am on the optifast only portion of the plan. it can get a little boring, but very exciting when the weight is literally dropping off of you that fast.

posted Mar 26th, 2010 2:38 pm


Just started on Optifast. This is my 2nd day. !st day not so bad. Today a little harder especially in the evening. That was my time to binge. I am fully committed to this so I am excited to see how much I lose. I really need it. Love the products. Was impressed at how good they taste. yum!

posted Mar 17th, 2010 5:36 pm


When i started the optifast program back in October , I was 5'2'' and 200 pounds. I am now 165 and kept it off. In the beginning, I didnt like the taste of it that much but I was sick of being fat. Now I actually like the taste of it and requested more of the optifast. If you stick to it and listen to your doctor you will lose the weight. The last time i was 165 was in 2003!

posted Mar 8th, 2010 11:52 pm


Hi I have lost from 358 to 343 in just 3 weeks on the partical optifast diet.It has been a struggle to not eat but it will be worth it in the end.

posted Mar 7th, 2010 3:28 pm


hesitant to start the program. cause if i lose the weight will i gain it back after i switch back to food

posted Mar 5th, 2010 12:49 am


Hi ,I have just started the parcial optifast diet.I have food for supper and the rest of the day I use the shakes and soups.I have started off to a good start.I set a goal of 50 lbs to start.I weighed 353 when I started.I hope it all works out.Will keep everyone updated..

posted Feb 11th, 2010 11:28 am


I tried to find an optifast program near me and found two but they are using the optifast to get there patients ready for bariatric surgery and I do not want surgery.

I was thinking of buying the product on ebay as it is available there but I feel the counceling and doctor visits are important. Any ideas on how I can do this diet?

posted Feb 11th, 2010 9:53 am


It is a way of life, not a diet. Optifast program has helped me to break bad eating habits while helping me shed those pounds to start my life on a healthy path.

posted Feb 7th, 2010 6:41 am


Greetings and Happy New Year! This is the first new year that I did not make a resolution to lose weight. Instead, I ran a 1/2 marathon in excellent time and really happy to enter this year and new decade on a high note.

As some of you know, I have been in a weight loss program since September. It has been an amazing 17 weeks thus far and I have been using OptiFast for 12 of those 17 weeks. I have lost a total of 86 lbs I started off weighing 256 lbs and as of this morning I weigh 170 (I'm 5'7").

I'd be remiss if I did not mention that in addition to OptiFast, my weekly one on one session are used to restructure cognition around food and the doctor requires that I walk 10,000 steps AND engage in some physical activity for a minimum of 30 minutes per day. Since Sept I have not missed a day of working out (I have not always reached 10K steps). My workouts include swimming, running and circuit training at the gym. The best parts of working out for me are feeling great afterwards -- even if I did not want to do it to start with -- and enjoying the physical benefits of being able to shop and wear clothes that actually fit.

There are 13 more weeks in the program and Tuesday I begin the transition phase where I curtail my usage of the OptiFast. I'd like to hear from some of you who have gone through the transition phase wit OptiFast. More specifically, how did you deal with eating food after being not eating it for 12 weeks (in my case)? Are there things I should expect? I'd really like to draw on your experiences and knowledge.


posted Jan 17th, 2010 9:24 am



I knew I needed to lose weight when I went skiing with my friends and realized I couldnt. I realized that if i fell, i was too big to be able to get back up.I started optifast Jan 2 and am really liking the diet so far. my doctor prescribed phentermine, and i think it is helping me from being hungry. The first day on phentermine, i felt a bit off (jittery and a headache) but that was the only day I felt bad on it. the shakes are good, especially strawberry. I weighed myself this morning (start of day 3) and have lost 5 pounds- so now Im 201 and 5'4. I'll keep updating everyone on how i do.

posted Jan 4th, 2010 2:30 pm


Happy Holidays to all. Dec 21 I weighed 318 for a total of 29ibs loss thus far. I expect from this point forward to average a loss of 5-7 pounds per week as long as I stay focused and stick to the plan.My goal is to lose 120 - 140 pounds. Continued success to all.

posted Dec 25th, 2009 9:01 pm


Congratulations on your weight loss Ruben! Way to go!!!

I, too, have been on Optifast. I am entering the 13 week of an overall weight loss/weight control program (but 9th week of Optifast). I have lost 71 lbs thus far and have really been amazed by my determination and ability to maintain such a strong commitment to the program. I am looking forward to eating food again but really think that the skills that I have acquired and refined will help me maintain the loss.

Initially working out has been difficult for me to do but has become increasingly easy. It helps that I bought some weights for home and on "lazy" days when I don't feel like going to the gym I do a circuit workout or yoga.

Good luck with your program and keep up the good work!


posted Dec 20th, 2009 11:18 pm



I am ending week three on the Optifast diet. I weighed in at 347 on November 30and at the beginning start of week two December 14 I weighed 325 pounds. I am happy with the results and religiously adhere to the 4 shakes,1soup, and 64 oz of water. I also walk on my treadmill and ride my bike every day for at least 30 minutes. I also have the support of my wife, family, friends, and colleagues at work. I am writing today because this has been a tough day for me and itis the first time that I can say that I have been truly hungry and hungry all day. But I am fighting through this and keeping focused on my goal and taking it one second, one minute, one hour, and one day at a time. I've got 17 more weeks to go and I believe I will be successful in reaching my goal of losing 130 and keeping it off.

posted Dec 20th, 2009 9:28 pm


So I forgot to update in early November. I am now in week 11 and have lost 47 lbs.

posted Dec 18th, 2009 5:48 pm


I started Optifast 1/12/09. I was 201.2 pounds (I'm 5'3"). On 9/15/09 I was down to 120 pounds. I've been on maintenance ever since. I go to my maintenance classes religiously. I still buy enough product so that I can have a shake for breakfast and a shake for dinner (I prefer a protein shake before I work out in the evening). I eat one healthy meal a day and two or three healthy snacks. I work out for one hour six days a week on an elliptical trainer. It's been over two months and I have maintained my weight at 120 pounds. I'm not always perfect and sometime find myself slipping but I use all of the tools I was given. Keep at it. You can be as successful as I have been. I know it's only been two months, but I feel completely in control.

posted Dec 6th, 2009 11:27 am


I have started the OptiFast diet two months ago. For the first month I monitored my eating habits and met weekly with psychologist. During this phase, I lost about 22 lbs. I have started the second phase -- solely using the OptiFast products for 12 weeks. I have lost about the same amount of weight so far that I lost during the first phase (where I ate my own food). Thus, I have lost a total of 46 lbs.

I'd be remiss if I did not state that in addition to OptiFast, I am walking 10,000 steps a day AND working out for 1/2 each day (sometimes more). This is and important part of the program and the most difficult part.

I only struggled the first few days on OptiFast but find the OptiFast products to be really good (how can it not be good given that Nestle make them!). I use a combination of all of the products daily. I typically have two ready-to-drink shakes, one powder, one bar and one soup. I also drink water, coffee, tea and Coke Zero everyday.

The best part so far is that I went from wearing a 40 waist to a 32 in just two months! I originally set out to lose 60 lbs and I am nearly there. However, I have decided to recalibrate my goal and lose an additional 25 lbs.

If anyone has any questions or needs support -- please respond to my post.


posted Nov 18th, 2009 7:15 pm


My name is Ruben and I am on week 5 of the Optifast Program. So far I lost 18 pounds. I did expect to lose more in this time but I realize I have not given this diet a chance to work 100%. I have stayed away from food but I would get a bag of popcorn every night I worked. I also put sugar and coffe mate in my coffee everyday. I decided to give my all to this diet to see what will happen. I will get my weigh in on Monday and will post the results.

posted Nov 5th, 2009 8:48 pm


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QUICK FACTSQUICK FACTS Start the Diet Now Advertisement
  • Established: 1974
  • Founder: Novartis Medical Nutrition Corporation; now owned by Nestle HealthCare Nutrition
  • Stock Symbol: NSRGY
  • Headquarters: Florham Park, New Jersey
  • Accessibility: Online, weekly one-on-one counseling
  • Diet Type: Meal replacement, liquid
  • Gender: Male, female

Do You Know the Best Diet Shakes of 2017?


The OPTIFAST plan has been considered the ace of liquid-based diets since 1974. The meal replacement drinks and bars are recommended by physicians for patients weighing more than 50 pounds over their ideal weight or with a Body Mass Index (BMI) of 30 or more. OPTIFAST is recommended to help obese individuals prepare for gastric bypass surgery as well. All participants have full access to professionals like doctors, dietitians and counselors.

The OPTIFAST program follows strict guidelines to ensure the health and safety of patients with three key areas of concentration - medical, behavior and nutrition. Patients have an initial medical exam to make sure they meet the program criteria.

Progress is monitored during weekly one-on-one and group counseling, to help encourage healthy lifestyle changes.

  • People will lose weight on the introductory phase
  • Your weight loss is monitored by their experts
  • Proven results with clinical studies and over 1 million participants
  • Program gives support and counseling along with weight loss
  • Medical monitoring while on the program
  • Offers decrease in cholesterol, high blood pressure and high blood sugar levels
  • Great tasting meal replacement shakes
  • Doubtful that most health care professionals would recommend being on a meal replacement plan for any extended period of time
  • Program consists of all liquid diet
  • May be cost prohibitive for some

To participate in Optifast, you must first complete a preliminary medical exam. You will be assessed to determine any risk factors and make sure you are a good fit for the program. After passing that exam, you are given a personalized weight loss plan that is based on your current weight and your goals. You are monitored throughout the entire process. Your meals will consist of the Optifast shakes and meal replacement bars.


You get a customized activity plan for your fitness level and schedule.


Maybe the OPTIFAST meal replacement is nutritionally sound, but there are plenty of other programs that have you making sound choices with real food. This program is also very expensive. This combination can only lead to the conclusion that there are other choices that would come before OPTIFAST.

Common MisspellingsCommon Misspellings

optyfast, opti fast, optifast progarm

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