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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 10 of 14, 272 total comments)


I would like to try this. My sister had great results and so did a co worker....but they both lost their hair in about month 2 and each had to have gall bladders removed after leaving the program

posted Feb 9th, 2009 10:27 am



Im in Australia and, like New Zealand, its available over the counter in chemists and for about $45.
When I was younger I used to do Optifast constanly on and off when I wanted to drop a few kilos in a week or 2 weeks... would usually lose about 3kgs a week without exercise (which is excellent considering I used to weigh only about 55-57kg)...
Have now gained alot of weight and am looking to lose about 15-20kg... so am now on day 4 of Optifast and hopefully I can pull it off! :)

posted Feb 5th, 2009 12:51 am


I am doing this optifast because I have to do it before I can do gastric bypass surgery I am a mom of 3 zand before them I weighed 135 lbs now I weigh 267lbs can someone tell me if I lose the weight am I gonna gain it back in 1 month after?

posted Feb 4th, 2009 10:20 am


I had always been in sports and always active! I had my daughter 2 years ago. I weighed 135lbs. when I got pregnant, I didn't eat "a lot" b4, but was forced to eat 3 meals a day (at least) while pregnant or I was consistantly sick. (My doc. thought I was having twins-what a confidence boost!). My daughter is 2 years old now, and I still weigh what I did after I had her...200lbs. Talk about not wanting anyone to see you! I had a lot of probs. after I had her and wasn't physically able to exercise. Being this large I am now on a "mission" to lose this weight! I am at the point that I HATE food! No, really I barely eat! And I can't lose anything. I've always been athletic, skinny, but ever since I had my daughter, this fat is "stuck" on me! I'm depressed and can't stand for anyone including my husband to look at me, let alone do anything else with me...My first session is 2/18/09 and I am hoping this will help, I would do anything! If I had the money I'd have everything nipped ,tucked, and sucked out of me. I have read the success stories...I HOPE I am one!!!

posted Feb 2nd, 2009 1:39 pm



I did a similar program at a clinic. It is great because you can treat food addiction by abstaining from it while learning new eating behaviors in class & groups. The re-gain rate is high IF you do not attend a maintenance program for a year or two after stopping the shake phase. I work with people who did Weight Watchers or TOPS after the shake phase b/c these programs are less expensive. Both have kept off 60lbs+. You are not hungry at all after the first 4 days. Best plan I've ever done.

posted Jan 18th, 2009 4:53 pm



I have been on the program for two weeks now, my first week I lost 6.3 lbs waiting for my next weight in every Monday. I also encourage the attaining the group sessions very informing. It's a very motivated program, you have to have the will power. I have my first shake at 9AM, Noon, have a piece of fruit at 3PM and dinner at 6PM with my last shake at 9PM plus taking my vitiams, calcium & fiber in the morning. Good luck to eveyone..

posted Jan 16th, 2009 7:06 pm


Yes, my insurance pays for the program without it I would had to try a different source. I just pay for the product and Doctor visits as required.

posted Jan 11th, 2009 5:17 pm


I just started it today and I have a big headache right now but I am sure by day 3 ill be good as rain :)

posted Jan 7th, 2009 1:27 am



Does anyone's insurance cover the costs? I am considering starting the program, but the costs kind of concern me...

posted Jan 2nd, 2009 11:23 am



I heard the shakes taste like yoohoo's? Is that true?

posted Dec 30th, 2008 3:56 pm



I lost 65 lbs using Optifast from August 07 - December 07. As of today (Dec 30, 08) I have gained 40 lbs of it back. I start again at the top of the year. Once off the fast this time, I plan to begin a workout regimen.

posted Dec 30th, 2008 5:59 am



2day is day 8 on this stuff.i need to lose 50lbs for hernia operation.so far so good miss eating alot,even went grocery shopping with a friend(that was hard) and had a breakfast meeting at work..thank you black coffee..havent weighed since start but feel okay...we will see

posted Dec 10th, 2008 9:13 pm



I have lost 45 pounds in a matter of 2 months I due the optifast 2 shakes and bars and a healthy meal for dinner

posted Dec 9th, 2008 9:35 am



The Optifast diet will help you lose weight, but in the end it is up to each individual to change eating patterns and behaviors. I was on the Optifast program for about 5.5 months and lost 35 pounds. The first week was horrible, depressing and everywhere i went all i saw was food. After my first weight in i lost 13 pounds, i was so motivated. After the second weight in i lost 2 pounds, i was angry. I followed the plan exactly as my doctor said but i was losing 4 pounds there 3 pounds here. I still kept with it though and the weight loss allowed me to start excercising again. It wasn't only about the weight loss, my whole attitude about food and eating changed. I use to walk by my favorite restaurants and wouldn't even notice them. I missed eating real food so much that when i did start eating again i had no problem eating vegetbales and other "healthy" foods. Unfortunately i gained all the weight back because i stopped goign to my doctor and did not finish the program. It got to the point where it was either optifast or rent and gas money. My doctor would charge $70 every visit just for the weekly weigh in. He charged about $50 for the phentermine and $20 for the laxatives. It got to be too much money. I place the blame on myself for gaining my weight back because i fell into my old traps again and i didn't make time to excercise. If you are really overweight and need to lose a lot of weight, this diet will help you but it is very expensive and mentally challenging. If i could find a less expensive doctor or avenue i would def go back to it again to lose what i gained back. Good luck to all!

posted Dec 2nd, 2008 10:15 pm

Dr. Primack


When using Optifast as formulated and directed, you should not need any other supplements (such as potassium or magnesium). It is already added to the shakes and soups.

One of the benefits of seeing a physician for weight loss is as these or other concerns arise, you have a knowledgeable souce for information.

posted Nov 19th, 2008 10:39 am

wo fat


the first time i did it i lost 35 pounds in 6 weeks, over the next 2 years i put the weight back on so did it again, same great results .
here in spain the product can be purchased over the counter.
when i did it in america the first time the price was obscene with the doctor as a middleman.
i think there were some online sites , so unless you have a medical condition other than being fat i recommend doing it yourself
remember to drink lots of water
i also take a multimineral as the water depletes your body of some of these.
another thing to remember is once you start a liquid diet and flush yout your digestive tract you will have lost about 8 kilos which is the amount of gunk we constantly carry with us
good luck

posted Nov 19th, 2008 6:43 am

Mrs Jones


So far I've lost 30+ lbs in 10 weeks.

posted Nov 11th, 2008 1:57 pm



I have been on the program for 17 weeks. It should be medically supervised. Sandie, you might be having stomach problems because you need to take a potassium supplement. When you are on a fast such as Optifast, your potassium levels drop. One side affect is stomach problems, among others. For this reason and others, it should be medically supervised. It is also a complete weight loss program. When if done correctly, explores deeper topics such as food choices, body image, reasons and situations when one over eats, eating disorders, and many other topics. The weight loss part is just the begenning of the program.

I recommend it, but beware it is not easy to be on a liquid only diet with no food. Yet, the rewards are huge. I am a male and I am losing about 5-7 pounds per week. The first week was horrible. Afterward, I felt great. I play sports for about 2 hours now five times a week and feel great. I've lost 85 pounds and still have 50 to go. So, another thing to consider when trying to diecide if this diet is right for you is if you have a lot of weight to lose. I had over 100 pounds so this diet is good because it gives results fast. Remember though, you want to go beyond the quick results and change your eating habits and overall way of thinking if you want to maintain the weight off. That's why it is important to go through the entire program. Good luck to everyone!

posted Nov 7th, 2008 12:41 am



Hi everyone,I live in NZ and we can buy it over the counter here for $62.00. This is my 3rd day on it,only have 15kg to loose.I am finding that it is giving me diarehoea and was wondering if anyone else is having this problem.

posted Nov 4th, 2008 2:32 am



I need to loose weight, I cant take it anymore, my problem is not overeating I accutually dont it much, and im walking more than ever, I want to try optifast I heard its a good weight loss program , I am going for my 1st appt on tuesday but before I go can someone tell me how much does this cost? thanks

posted Oct 30th, 2008 11:15 am


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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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