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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
  • .

> Leave Feedback

User Feedback

(Page 13 of 14, 272 total comments)


I have been doing this diet MODIFIED, (which means 3 shakes, 1 nutrition bar, one real food snack and one real food meal). The weight loss is slower, but I have been able to stick with it through Thanksgiving, Christmas, my birthday, etc. - 16 weeks and I lost 27 pounds - almost halfway to my 60 pound goal. I find it is easy, does not involve a lot of measuring, weighing, calculating and thinking about it. Have controlled my borderline diabetes, and lowered my blood pressure.

posted Mar 5th, 2008 9:38 am


I just completed my first week on the program and have lost 6 pounds. I only want to lose a total of 30 so only 24 more to go! If you mix the shakes in a blender with diet sodas they taste much better. My favorite is diet orange and vanilla shake! I use Benefiber in my shakes in the morning...can't taste it at all. Another favorite is to mix decaf coffee with a chocolate shake (either hot or even with ice for a treat!!) It really hasn't been too bad. The hunger is bad but I hope that it will get better!!

posted Mar 3rd, 2008 3:28 pm

Ak Chris

Well I am now into my fourth week of opti fast. I have lost 20lbs in three weeks and i feel great. After the second week my Doctor adjusted my program I now have four optifast products a day and i am allowed 460 calories. So can have some real food and it is great!! love it so far

posted Mar 3rd, 2008 8:02 am


I have been on optifast for 18 weeks...I lost 53 llbs and am 20 from my goal weight...i will transition back to whole food then back on opti for he last 20...i was considering bariatic but was just shy of the weight I needed to be to qualify. I'm riding my horse 4 days a week now like I used to before I gained all the weight and can't wait to make goal. I really like this program.

posted Feb 25th, 2008 7:48 pm


I am going on my 4th week on the oprifast and I think its going ok. The first couple of days were really hard but everyday now gets easier. I feel better I think i have lost about 18 pounds. I use the taranis flavoring in my shakes to add flavor and drink a lot of water. I also use an off brand of crystal light to flavor my water.


I am going on my 4th week on the oprifast and I think its going ok. The first couple of days were really hard but everyday now gets easier. I feel better I think i have lost about 18 pounds. I use the taranis flavoring in my shakes to add flavor and drink a lot of water. I also use an off brand of crystal light to flavor my water.

Australian Angel

I am in my third week of the opitfast program, my first goal is 15kg then I am hoping to have a short break before challenging my next goal of 5kg. I have a shake for breakfast, a bar for lunch and a calorie controlled meal for dinner (avoiding carbs) it is getting easier however I am also experiencing constipation. I tried a laxative but they are too extreme, I am currently drinking 1/2 cup of prune juice morning & night which seems to be working so far. Sometimes I have a pear which is great too. I have lost 3.5kgs so far next weigh in 4 days. I don't find it expensive, I order online at www.onlinechemist.net.au there prices are about 20% cheaper than at the shops. I love the chocolate bars, they taste like space food stick. Yummo!


I am now on day 5 of being on the program. Even though I am drinking all the water required, I feel very constipated. I do not like to take medicine or metamucil. Do you have any suggestions of what I could eat along with the optifast to get that added fiber?

Ak Chris

I am on my fourth day of the diet, And let me tell you it has been tough for me. All I can think about is eating all my old favorites. Like pizza toca bell..etc.. I can almost taste them. It really is taking everything I have to not stay away from the diet. My first weigh in is on friday the 15th. I hope to see results.


I'm going to start the program this week. I'm really excited. I weight 222 lbs and I'm only 22 years old and I'm about to graduate from nursing school. I'm not the model of health that I want to be for myself and my patients. Any good suggestions for the first week?


It sounds like there has been a lot of success with OPTIFAST. I work on the marketing team for OPTIFAST and love hearing your motivating stories. There is a place on OPTIFAST.com to submit your success stories. We would love to hear from you!

Mrs. Johnson

I have always been heavy my whole life. My boss (honorary other father) started the program Optifast and lost 75 pounds. He told me about this diet. I begin on the 19th of February 2008. I am so excited for a new healthy 2008. Way to go for all those who have lost and loved this program... :-)


I did the diet years ago. I gained it all but I was also very young. I have been through 2 weight loss surgeries and many many diets. I gained about 35 pounds after the last surgery. I want to lose that. I think this will actually really help. I think I am going to do it. Maybe this summer will be more fun.


ive beendoing this diet for a month and a half and ive lost 30 pounds! you just gotta stick to it and it really works! and Exercise!


How much water is one required to drink on this diet?


i did this years ago ... and I have gained it back... my doctor had me mix the vanilla shakes with diet drinks to get flavors... I used cola, root beer, and orange,,, I even bought cake flavorings from the bakery supply store, I just didn't want to get bored... actually, they didn't even have the bars and the soups when I did this....more choices.


Just wondering with the weight coming off so quick if any of you are having issues with the skin not going back? Have you or will you have a tummy tuck because of the skin elasticity?

sammy joe

wow. y'all crazy. you dont need diets or sugery. changin ya weight is mental and a complete lifestyle change. and when y'all lose the weight you keep living healthy. diets are dumb and can kill you!


Weight comes off very fast and comes right back on faster. I was so ready to eat and once I started I couldn't stop. Gained all back ++++. Cost was over $3500.


I have been on the diet for 16 weeks and have lost 70lbs. Its not as expensive through kaiser. I pay about $105 a week. Its a great program but you have to be willing to work out the reasons why you eat. For me, I had to work through my depression. Yes this diet is hard for the first 2 weeks but after you see the weight come off, it becomes so motivating that you don't want to get off track. I would recommend this diet to people who really want to change their life style.


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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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