Optifast is a diet program I will surely never forget. We at DietSpotlight decided to create a comprehensive review, scrutinizing the ingredients, side effects, customer-service quality and clinical studies. Moreover, we read dozens of user comments that are posted online. Lastly, we compacted everything we found to give you the important facts you need.
What is Optifast?
To start, Optifast is boasted as “the serious solution for weight-loss” and it is suitable for both adults and teenagers with a body mass index (BMI) of 30 or greater.  Basically this is a medically supervised program that’s intended to help with weight reduction and overall health.  It typically lasts for 26 weeks. This program involves the following; meal replacement diet, medical supervision, lifestyle education, counseling and ongoing personalized support. There is a tool provided on the official website that allows you to pinpoint the nearest clinic location, so you can get started. The products from Optifast include shakes, soups, protein drinks, nutrition bars and vitamin and mineral supplements, which are made by Nestle.
Optifast has been around since at least 2010, and the official website is very informative. There are clinic locations all over the United States and Canada. Also, a helpful FAQ section is provided on the website, but read on…
High Cost –”Concerning?”
The first issue we found was what the dieter was expected to pay.“We did some digging and discovered that the actual cost of Optifast is quite steep. In fact, this weight-loss program may end up costing you well over $1,000. This is especially true if you stick with it for the full 26 weeks,” says our Research Editor. 
- According to one customer, “There’s a reason they don’t post what their prices are! Here’s the price breakdown I was given: $600 lifestyle mgt class membership (some insurance covers this), $122.50 Optifast per week and $185 Enrollment fee. For the privilege of just being there!”
- “The Optifast program in my area costs $995 to start and $320 a month, plus your cost of food and supplement shakes are $37 for 18, so if you are drinking 3 to 5 a day…well you can do the math. On the “healthy solutions” it would cost $653 plus diet pills at $75 for 180 a month. You also have to pay in advance,” said another dieter.
We were unable to find a single customer who felt the price was justified, but there are many who try out the program – so it may be cost-effective for some users.
Negative Dieter Reviews of Optifast
There are some serious complaints regarding the taste of Optifast foods and supplements. This is never a good sign. 
- One customer complained, “The chicken and vegetable soups are disgusting!! After a couple of days of trying to get them down, I stopped using them completely.”
- Another person stated, “This is my first day and I have no idea how I’m going to do this…I can’t stand the taste of these shakes and they make me feel sick.”
We have to look at the other side of the coin. 
- One buyer said, “I have been very pleased with this product. I thought I could hold fast to no food, but two weeks I have to admit I was tweaking.”
According to our research, if there is some certain aspect of a diet program that is very annoying or concerning (high cost, negative dieter reviews, a difficult exercise) the likelihood of prolonged weight-loss success is minimal.  So, if Optifast does in fact taste bad or lead to unhappy customers, this could be problematic.
The Science – “Solid?”
Since Optifast is monitored by medical professionals, there is some real science and clinical tests involved to better ensure weight-loss results.  Here at DietSpotlight, we prefer to see actual science that supports the diet program or weight-loss supplement. Unfortunately Optifast does not really elaborate on clinical studies on their website.
Even though Optifast is regulated by medical professionals, we feel that the negative dieter reviews and very high cost are major drawbacks. 
The Bottom Line – Does Optifast Work?
So, should you spend your money on this one? Well, we like Optifast’s professional clinics and that they offer various supplements to assist dieters. On the other hand, we have some concerns about this diet program because it’s so expensive. Also, we have some reservations about the numerous negative dieter reviews posted online. 
If you’d like to get rid of serious pounds, we encourage you to find a diet program or weight-loss formula that is affordable, easy to use and backed by plenty of customer testimonials.
Among the best products we’ve seen this year is one called Leptigen. This product contains four unique ingredients, which have been shown, via clinical testing, to possibly help speed up fat loss and boost metabolism. It’s also amazing that user reviews posted online reveal people are seeing solid results.
Also, the makers of Leptigen are so confident in the formula, they’re offering a Special Trial Offer, which is encouraging.
Previous Optifast Review (Updated September 20, 2014):
What You Should Know about Optifast
Optifast is a weight loss program that uses meal replacement products to help people lose weight. The Optifast meal replacement products are produced by the famous dessert giant Nestlé, of all companies! The Optifast meal replacement products consist of Ready to Drink Shakes, Powders, Soups, Nutrition Bars, High Protein Drinks, and a Optifast Vitamin and Mineral Supplements. Nestlé says that the Optifast weight loss program, as well as involving meal replacements, also incorporates, medical monitoring to assess your progress and offer encouragement.
List of Optifast Ingredients
Apart from for the Optifast Vitamin and Mineral Supplements, there were no comprehensive ingredients that we could find for the Optifast replacement meal products.
The ingredients listed for the Optifast Vitamin and Mineral List are, Vitamins, A, C, D, E, K, B6, and B12, Folic Acid, Acid Biotin, Pantothenic Acid, Thiamin, Riboflavin, Niacin,Calcium,Iron, Phosphorous, Iodine, Magnesium, Zinc, Selenium, Copper, Manganese, Chronium, Sodium.
The Optifast weight loss program, as well as including meal replacement products, also consists of medical monitoring. Nestlé says that if you subscribe to the program you will also have a thorough medical examination at the beginning of the program, and any necessary laboratory tests to rule out any risk factors and to determine your health status. There will also be medical monitoring of your progress, and you will be given a personalized activity plan. You will also be able to partake in discussion groups and have the opportunity to have one-on-one counseling with a registered dietician, lifestyle counselor, or a physician. There is an official Optifast website, but it seems that in order to access the weight loss program you will have to make an appointment at an Optifast Clinic. The website does not give any details of the price of the program, nor the price of the meal replacement clinics.
Advantages of Optifast
- There is an official website for Optifast.
- The program includes medical monitoring.
- The website is sophisticated and easy to navigate.
Disadvantages of Optifast
- The website does not give details of the cost of the weight loss program.
- You cannot order the meal replacements on line.
- You can only undertake the Optifast weight loss program in conjunction with an Optifast Clinic.
- Having to stick to a pre-prepared diet of Optifast products could become difficult.
- Though few details are given, it sounds like frequent clinic visits could become time consuming.
The Optifast weight loss program does seem to be one of the more serious weight loss program on the market. If what the official website says is correct, the program involves careful medical monitoring and emotional support, as well as a strictly controlled diet. The website does not give any details of the cost of the program, so we do not know if it is easily affordable or what expenses are involved in subscribing to the program. Considering all of the attention users receive from trained professionals, we would imagine it’s relatively expensive. Additionally, the program does not allow for much freedom in a user’s diet. While all of this attention could be beneficial to obese users who need to lose weight badly, those looking to drop a few pounds for aesthetic reasons may want to find something simpler and cheaper.
Optifast Questions & Answers:
We boiled down hundreds of user comments about Optifast into this helpful FAQ.
What are the side effects of Optifast?
Optifast side effects may include hunger and fatigue. 
What is in Optifast?
Optifast ingredients vary depending on the foods or supplements you’re using.
What is the active ingredient in Optifast?
The active ingredient in Optifast is protein.
Does Optifast work?
Many people have had success with Optifast. However, there are no studies available on the official website proving you will lose weight using this program.
How much does a bottle of Optifast cost?
The cost of a bottle of Optifast varies, considering this is weight-management program. If you take into account meals and visits to the clinic, could easily exceed $1000.
How do you take Optifast?
How you take Optifast products based on your individualized program.
Can I take Optifast if I have a health condition?
Women who are pregnant or nursing, those with health conditions, anyone taking prescription medications or people under 18 years of age should consult with a healthcare professional prior to starting any weight-management plan, including Opti.
What do users like about Optifast?
Some users liked that they saw results while following the Optifast program.
What do users NOT like about Optifast?
Many users complained about the high price of Optifast.
Who makes Optifast?
Nestlé HealthCare Nutrition makes Optifast.
How do I contact the Optifast customer service department?
You can contact the Optifast customer service department by calling 1-800-662-2540, using the feedback form or by mailing letters to Nestlé HealthCare Nutrition Consumer and Product Support 445 State St. Fremont, MI 49412.
Can I contact Optifast through social media?
Is Optifast covered by insurance?
This depends on the insurance company you use and the level of coverage you have. Contact your provider prior to beginning the program to find out what, If anything, they cover.
Can I eat food while on Optifast?
Opti is a three phase program. During the first 12-weeks – the active weight-loss phase – you will consume full meal replacements with Optifast products. During the transition program, you move to eating regular food you make yourself.
Is Optifast right for me?
Optifast is best for patients with a BMI of over 30. It is recommended only as part of a comprehensive treatment program. 
Does Optifast come with a guarantee?
No, Optifast is not supported by a guarantee.
Do you know of any special deals or discounts on Optifast?
The official Optifast website doesn’t mention deals or discounts. However, our readers have been going crazy over the past few months taking advantage of Leptigen’s Special Trial Offer. Click above to learn more.
Optifast User Tips:
7 Top User Tips
Over the years, we’ve seen that Optifast users have something to say. After analyzing thousands of comments and reviews, these are the tips that we think will help you learn the most about this program.
“If you are serious about doing a liquid diet it is important to do your research so you know exactly what you’re getting into. That way your expectations won’t be unrealistic.” Gabbie
“It is a doctor monitored weight-loss program. You will go to the doctor’s office and have to spend the time doing that. There is a definite time commitment.” Mike
“I buy the mixes and mix it with almond milk or water because it is less expensive.” Jessie
“I prefer the taste of the liquid version. Nothing made the mixes taste good.” Sherry
“The price can get out of hand pretty fast if you buy all of the add on stuff like vitamins, protein powder, and the bars. But it CAN be done on a budget if you are careful.” Mike
“The first week is so hard. I felt like I was going crazy because of the reduced calories and not being able to eat anything. But once you see results it becomes easier.” Mel
“Losing the weight is one of the hardest things I’ve ever done. I had to take a break after seven weeks because I couldn’t handle the shakes and no food anymore. Now I’m cycling on and off.” Lacy
Optifast Scientific Abstracts:
Ingesting fructose triggers insulin resistance, hyperinsulinemia, impaired glucose tolerance, and hypertension in animals. Data regarding these findings in human participants is less clear. There is information and data on the metabolic and endocrine actions of dietary fructose that indicate elevated consumption of fructose can be destructive in terms of body weight and adiposity as well as the metabolic indexes that come with insulin resistance syndrome. There needs to be more research in order to fully comprehend the metabolic effects of dietary fructose in humans. 
Participants in the high protein group displayed better weight management following weight-loss (2.3 kg difference, P=0.04) as well as fat mass decrease (2.2 kg difference, P=0.02) in comparison to participants in the high carbohydrate group. Triglyceride (0.6 m mean difference, P=0.01) and glucagon (9.6 pg ml (-1) difference, P=0.02) concentrates were raised more in the high carbohydrate groups, while glucose (0.3 m mean difference, P=0.02) was higher in the high protein group. Alterations to total cholesterol, high-density lipoprotein-cholesterol, low-density lipoprotein-cholesterol, insulin, HbA1c, HOMAir index, adiponectin and leptin concentrations had not changed regarding the diets. It was concluded that low-fat, high-casein or whey protein diets are better for weight control when compared to a low-fat, high carbohydrate diet and do not negatively impact metabolic and cardiovascular risks in moderately obese patients. 
Soy Protein Isolate
There had been small alterations in body weight gain profiles, but other than that CAS-, SPI- or WPH-fed rats had not altered in development, in vitro hepatic metabolism of testosterone, organ weights, or reproductive performance. There were some endocrine-related functions differing between the rats who were administered the proteins. It was found that soy protein isolate had sped up puberty in female rats (p < .05) while whey protein had slowed puberty in males and females alike when compared to casein (p < .05). The meta-analysis of the results had indicated that gender-specific alterations in development and specific endocrine reactions in the rats that were fed diets containing a single protein source like those used in infant formula. It is unknown whether there would be similar effects in humans, but is thought to be unlikely as most infants do not ingest such diets throughout their lives as the ones given to the rats. None of these effects have been reported within the millions of American infants who were fed instant formula with the same proteins. It had been concluded that the long-term health benefits (reduced breast cancer incidence) of soy protein isolate and whey protein are very likely to be positive. 
- 1. Fructose, weight gain, and the insulin resistance syndrome (2002). The American Journal of Clinical Nutritiion. November 1, 2016.
- 2. The effect of a low-fat, high-protein or high-carbohydrate ad libitum diet on weight loss maintenance and metabolic risk factors (2009). International Journal of Obesity. November 1, 2016.
- 3. Developmental effects and health aspects of soy protein isolate, casein, and whey in male and female rats (2001). International Journal of Toxicology. November 1, 2016.
Optifast Side Effects:
Natural weight-loss supplements don’t come with a guarantee that you won’t feel off after taking it. Negative reactions are possible with any type of formula, even one made with natural ingredients. While Optifast side effects don’t happen often, they do exist for some users.
When you start to feel discomfort or weak because you haven’t eaten recently, it’s called hunger. It comes with a desire to eat and may even come along with specific cravings.
What causes hunger?
Hunger is caused by many things. In some cases it’s not voluntary and it’s caused by a natural disaster, such as a tropical storm, flooding or a long period of drought.  Other times, hunger is caused by a reaction to medication, a supplement or exercise.
A feeling of extreme tiredness or a feeling that you’re completely drained is known as fatigue. Athletes may suffer from fatigue after a performance, while others may suffer from it on a daily basis.
What causes fatigue?
Overexertion may cause fatigue, but it may also be caused by an allergic reaction to food, medication or a supplement. You may also feel fatigued if you don’t get enough sleep at night or due to stress. If you feel weak and tired all the time, you may suffer from chronic fatigue disorder.
When it becomes very difficult to empty the bowels, it’s known as constipation. Usually, feces have hardened and you’ll feel like you’re straining. Your bowel movements won’t happen as regularly and you may end up with a swollen abdomen.
What causes constipation?
A very common cause of constipation is stress. While we don’t always realize it, stress manifests itself physically. It’s also caused by irritable bowel syndrome, digestive disorders, some medications and various supplements.
Diarrhea is loose bowel movements. If you have loose stools three times or more in a day, it’s diarrhea. The mild variety may only last a short time and it’s rather common. However, if it lasts for more than a few days, it could be a sign of something requiring medical assistance. 
What causes diarrhea?
Contaminated water or food will often cause diarrhea due to the bacteria. It may also be caused by a virus, parasite, food allergy or negative reaction to a medicine or supplement. Sometimes, it’s caused by something more serious, such as irritable bowel syndrome or Crohn’s disease.
Most users won’t experience Optifast side effects, but some have reported hunger, fatigue, constipation and diarrhea. Before taking any new supplement, you should always speak to your physician, especially if you’re under 18, pregnant or nursing, suffer from a current medical condition or you’re taking any type of prescription medication.
We know that adverse reactions are rare. One that’s caught our eye is one not associated with harmful side effects is one called Leptigen. Click above to learn more.
Optifast is a meal replacement shake that is designed to curb appetite and over time, promote weight-loss. We understand that side effects don’t always happen, but, through these comments, we proved that they can still happen.
“I can’t stand the taste of these shakes and they make me feel sick.” Annette
“I am on my third day of the Optifast program. I am still really hungry and I feel a little light headed.” Tanya
“I am on day two and having bad diarrhea.” Monica
“I’m experiencing bloating… I’m also getting constipated.” Rose
“I am sweating like crazy every day and recently I am having diarrhea and vomiting…” Carine
“She [my daughter] is starting to have stomach pain.” Diane
“I found myself sweating profusely and not feeling good.” Gabby
“…I feel very constipated.” Marty
“I felt exhausted and almost fainted at work.” Rachel
Optifast is a self-proclaimed "serious solution for weight loss." It comes from Nestle Health Science. You visit a clinic in your area to start the program. There are meal replacements, soups, bars and supplements. It appears that the shakes are the biggest product.
Optifast Ingredients and Supplement Facts
Serving Per Container: Varies depending on product
|Amount per Serving||% DV|
|Nonfat Dry Milk||*||*|
Other Ingredients: Salt, 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 palmitate, niacinamide, copper gluconate, calcium pantothenate, manganese sulfate, vitamin D3, color (beta carotene, turmeric oleoresin), pyridoxine hydrochloride, thiamine hydrochloride, riboflavin, chromium chloride, folic acid, biotin, potassium iodide, sodium molybdate, sodium selenite, vitamin K1, vitamin B12
We really researched the Optifast ingredients in order to give you the facts you need.
Sodium caseinate is basically a type of protein that is found in milk. It is often used in fitness shakes, protein bars and other supplements. This substance provides amino acids, calcium and carbohydrates as well. 
What is it Supposed to Do?
Typically sodium caseinate is added to supplement powders, bars and shakes for its protein content. This protein helps reduce appetite, promote lean muscle mass and repairs, and boost energy levels.
“Several studies support the theory that when it’s taken as part of a low-calorie diet, casein has a potential to encourage weight loss. In one study published in 2009 in the International Journal of Obesity researchers demonstrated that high-protein diets featuring casein were just as effective at producing long-term weight loss and weight maintenance as diets featuring whey protein.”
Soy Protein Isolate
Soy protein isolate is an alternative to animal-based proteins. It comes from soybeans, and is free of saturated fat and cholesterol. This substance is used in a number of supplement powders, protein bars and shakes.
What is it Supposed to Do?
Like other protein ingredients, soy protein isolate is intended to help build lean muscle mass, minimize recovery time after workouts, and help keep you full. It’s low in calories, so it’s often used as a meal or snack replacement.
“According to a 2003 article published in The Journal of Perinatal Education, genistein, one of the phytochemicals in soy, can help reduce the risk of cancer. Soy protein can also help control high blood sugar, promote a healthy body weight and help lower bad cholesterol and triglycerides, according to the authors.”
Calcium caseinate is found in countless workout supplements and protein powders. It is derived from the casein in mammal milk. It actually breaks down in the body more slowly than whey protein. Furthermore, it provides amino acids to benefit the muscles.
What is it Supposed to Do?
Calcium caseinate is used in many supplements to help stave off hunger, assist with muscle growth and improve athletic performance. However, it has not been shown to speed up weight-loss. 
This ingredient may help with muscle building and maintenance. According to the University of Michigan Health System, “Casein is a complete protein, providing generous amounts of essential amino acids. However, it is digested more slowly than most other animal proteins, resulting in a more prolonged release of amino acids into the bloodstream.”
One that’s caught our attention is one called Leptigen. It contains clinically-tested ingredients and has been shown to work. Want to learn more? Click above.