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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 3 of 14, 272 total comments)


I have been on Optifast diet for 4 days. I cheated and had 2 bits of a hambuger on the 3 day. I have only lost 5 pounds. how long after you cheap on this diet does it take our body to get back to ketosis? also does anyone know if their is another shake that compares to the optifast shake? the optifast shakes are to expensive for me to continue to purchase.

posted May 1st, 2012 6:16 pm

Lauren Redmond


I have been on the diet for 5 days now and I have lost a little over 10 lbs. I have to say the hardest part is giving up the foods I love, but I have not been hungry. Looking forward to seeing the results after a few more weeks.

posted Feb 21st, 2012 9:58 pm



Works great! It's not easy but the weight will fly off. Have lost 28lbs in just over one month and two weeks.

posted Feb 12th, 2012 3:42 am


I tried this diet 18 months ago. I was on the straight liquid diet and lost 47 lbs in 12 weeks. I have been able to keep the weight off. You have to be VERY discipline and don't cheat. Its too expensive not to give it 100%. My only regret is the "saggy" skin. It has taken me almost 15 months to get things toned up.

posted Jan 29th, 2012 9:45 pm



what can I do to make the shakes and bars taste better? today has been day 1 for me...and I honestly don't know how I'm going to do this for 3 months!! The shakes do not taste great and the bars are horrible! I haven't tried the soups yet, I don't even like tomato, so I hope they are better than the shakes and bars. I have younger kids so it was hard to make them their meals because they can eat regular food. I'm already feeling the craving for something real!!I know I need this and I'm willing to see how it works, just gonna need some motivation

posted Dec 24th, 2011 3:51 am

jan oye

l was on optifast and got very, very sick with migraines and heart palpitations, l found out 4 weeks later after l quit the diet,because of getting very ill, l had an abnormal EKG to begin with and my doctor that put me on the diet never even told me, l reqested my records, the EKG was taken the day the dr put me on the optifast diet, and he NEVER even told me l had an abnormal EKG, obviously he was in it for the money and not my well being. There will be consequences for him.Be sure to request seeing all your tests before starting the diet, none of mine were brought to my attention,l am extremely disappointed in that physician.

posted Dec 19th, 2011 1:48 pm



I have been on the Optifast 900 4 Shakes/Day plan for 8 days, and have lost 16 pounds. Mostly water, but I can honestly say I have not been hungry. The first 4 days were a challenge, but after that initial point I feel like I have gotten past the most difficult phase. I will now be switching out on shake per day for a meal consisting of 6oz Lean Protein, Low Glycemic Index Vegetables, and a Maximum of 20g of Carbohydrates. (Low Glycemic Index Carbs). So this will be more of a challenge in that I have to do some Nutrition Research to plan my meals.
Basically the Optifast program is set up to put you in a state of Ketosis, similar to an Atkins or No Carb Diet. This diet is not for everyone, and it is not easy or "normal". A box of shakes cost approximately $300.00 Canadian/month for 4 shakes per day.

posted Dec 8th, 2011 12:38 am


Hi, I too will be starting Optifast next week. My eating habits are so bad that I am looking forward to 3 shakes per day and 1 light meal. Good Luck to you.

posted Dec 1st, 2011 9:56 pm



Can I do the Opifast diet if there's no clinic in my area? I do not have an Optifast clinic in my area but I have read everything online & I am ready to try this diet.

posted Dec 1st, 2011 5:34 pm


I start Optifast on Dec 15th, Im nervous about it because I was just diagnosed as a Diabetic II (controlled though) & Hypothyroidism. I am experiencing numbness in my right thigh and hand falling asleep when I lay on them while sleep. I think too much fat in those areas not allowing the blood to circulate. I really need to lose 100lbs. When I went to the orientation to my dismay I weighed in at 260lbs, since my work-up and starting 1200 cal diet and started meds synthryoid/metformin I now weigh 248lbs pre-optifast. Need some encouragement really bad.

posted Nov 28th, 2011 4:55 pm user comment


Hi Sharon
I will be starting on Nov. 2nd. So I wish you well. I think a support blog would be very helpful, so I am glad I ran across this page.

posted Oct 26th, 2011 5:40 pm



I will be starting the Optifast program on Nov. 1st., which is also my 66th birthday! This is my present to myself to lose weight! I have about 100 pounds to lose, so this is a big undertaking. But I am up for the challenge! I don't know if anyone knows it or not, but there is an excellent support page on Facebook for people who are on the program. I will be going through Kaiser for my program and I have been very encouraged by all of your posts on this site. I am eager to get started.

posted Oct 22nd, 2011 1:43 am



it has been six months since I stopped opti fast, when I first started the shakes I weighed in at 80kg, I actually lost 10kg in the month I was on optfast, after my diet I put on a couple of kilos but truthfully I am now 72kg and staying at that weight without trying, so YES, optifast is great, although I have a good eating habit I'm naturally a healthy eater, I would rather eat fruits for a snake rather then potato chips or junk, but optifast helped me keep cut each of my meals into half, as I feel fuller quicker then before I started my diet, I am very happy with my results and I do recomend this diestplan as it has honestly made me feel so much better about myself, I plan on going back on optifast for a month, just to lose some more kilo's for summer, but please know I lost 10kg in a month not just because of the shakes, I did some heavy duty working out, I did 40mins everyday minimum, so it didn't come off that easily..

posted Oct 11th, 2011 11:36 pm



I'm in the middle of my second week of Optifast. Kaiser wants us to drink a gallon of water a day (this counts the optifast drinks as part of that gallon). So a 20oz water bottle with each meal will do it. However, getting a night of uninterrupted sleep is a challenge since I have to be up every 2 hours to pee. I'm trying to settle on a schedule where I don't drink anything too late in the evening. It seems to be working. I started to cut back on my caloric intake after my initial meeting with the doctor and managed to drop about 8 pounds on my own in the two months before going on the diet. But now the weight seems to be dropping at a steady and safe amount. I'm happy as long as the trend continues in that direction. I've also joined Zumba and dance classes for exercise and a long walk on weekends. That seems to be helping too. I have 50 to 60 pounds left to lose to get me at a healthy BMI.

posted Oct 8th, 2011 3:13 pm

Gerri Leavitt

Anyone their Optifast shakes from drugdispensary.com in New Zealand and if so how do they compare to Optifast 900 shakes which are available locally - i'm waited to be accepted into an Optifast program and my local hospital is asking for $120-$130. per box but drugdispensary sells them for $57. per box - any info would be appreciated. A friend gave me a box of Optifast 900 and I've started them but too soon to say how much i've lost.

posted Sep 30th, 2011 8:07 pm


I just attended an orientation and hope to start Optifast in October. I'm going to blog about it hoping to give a realistic view of what the program is about and my experiences with it. I've been searching online all day looking for a blog to help me and couldn't find one. It seems most of the Optifast bloggers stop blogging after a short time on the program. I hope this isn't a sign. To read the blog go to: www dot leavingfatburgh dot blogspot dot com.

posted Sep 29th, 2011 6:23 pm


Today is my first day of the Optifast Diet! I was totally mentally prepared for this but my first day is already a disaster. I'm not really feeling the taste of the soups. I'm not really hungry but am already craving the sensation of actually eating regular food. Ugh this is gonna be a rough road. I already cheated and had a bite of a Fig Newton and a few bites of a cookie. Soo disappointed. But that's ok I can do this!! Getting back on track. Might have to go bed earlier today so I can stop thinking about food.

posted Sep 28th, 2011 11:08 pm


Hello everyone!

I'm on Day 13 of my Optifast diet and I've already lost 18lbs! :)

It hasn't been easy. I'm still craving but I know I can and I must do this. No one said it was going to be easy, but it'll sure be worth it.

I'm taking it one shake at a time. If you're on the diet now, know that you're not struggling alone.

Just remember...

One shake at a time. :)

posted Sep 19th, 2011 10:54 pm



I have done a version I modified so I would stick to it- 2 shakes, 2 snacks from the optifast lists, one proper meal and a yogurt for dessert. I find it is very useful and easy to stick to this way. I expect when I have lost the weight I will still use these shakes to make sure I always have a healthy meal with me- something which has tripped me up before.
I make sure to drink plenty of water before the shake or soup so that I feel fuller. I have done the three meal replacements, but I found it too hard, but am happy with my weight loss (on average 2- 2 1/2 pounds)

posted Sep 17th, 2011 8:01 am



I am really having a very easy time adjusting to it. Its a fantastic diet I have about 100lbs to lose now. Two weeks ago it was 115lbs I am down 15lbs in the first two weerks. The shakes are delicious.

posted Sep 15th, 2011 6:17 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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