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Instant Knockout Review

Note: This is a review, not the official website.  Click Here to visit the official Instant Knockout website.

If you’ve come across any of our articles on the height and weight requirements for a specific branch of the military, you may be feeling a bit frustrated.

The Army, Navy, Air Force, Marines, and Coast Guard can be pretty strict about their height and weight requirements.

Losing weight isn’t easy.

It takes a combination of diet and exercise, and only works if you’re 100% committed to it. 

What many don’t realize is, there are supplements out there that can help to speed up this process.

They won’t shed the weight off for you, as you sit around eating Cheese It’s all day, but they WILL help.

One of those supplements is the focus of today’s review, and it’s called Instant Knockout.

Attn Females:  While Instant Knockout can be used by women, you would be way better off with a supplement called Lean Bean.

It’s a fat burner that is specifically designed for women, click here to read our full review.

What is Instant Knockout?

instant knockout bottle

Developed by a company called Roar Ambition, Instant Knockout is a ‘revolutionary shredding formula’ that claims to activate whole body burn.

Originally developed for MMA fighters and professional boxers, their formula is reportedly based on scientific research and intended to:

  • Help burn stubborn fat deposits
  • Increase metabolism
  • Reduce hunger cravings
  • Increase energy levels

How Does Instant Knockout Work?

According to the official website, Instant Knockout is designed to attack your fat stores by increasing your metabolism.

It’s a 3-pronged attack that works as follows:

1. Boosts Metabolic Rate

According to Wikipedia, your metabolism is essentially the “chemical process that converts food to energy to run cellular processes, convert food / fuel to building blocks for proteins, lipids, and nucleic acids, and the elimination of nitrogenous wastes”. (Source)

In less-scientific words, it’s your bodies fat burning source.

When you have a fast metabolism, your body burns fat at a high rate.

When you have a slow metabolism, your body struggles to burn the fat, and stores it as a reserve (usually in your mid-section for men, and butt and thighs for women).

2. Appetite Reduction

The ingredients in Instant Knockout (discussed in detail below), are also potent appetite suppressants.

Losing weight / keeping the weight off is really a matter of calories in being lower than the amount of calories burned in a typical day.

For example, let’s say you need 2,000 calories a day to maintain your current weight.

If you eat 300 calories less per day, you’ll lose weight.

If you eat 300 calories more per day, you’ll gain weight.

Instant Knockout is apparently designed to help you eat less calories, resulting in substantial weight loss.

3. Fuels Energy Levels

Apart from eating less, you’ll also need to workout. 

When you’re eating less calories, you’ll have less energy to workout (which can be a problem).

This is where Instant Knockout is supposed to shine.

Instead of being tired and lethargic, it apparently will help to fuel your bodies energy reserves, allowing you to push through a sustained workout.

A Detailed Look at the Ingredients In Instant Knockout

It does this through a unique blend of 10 ingredients that include:

  • Green Tea Extract: 500 mg
  • Cayenne Pepper: 100 mg
  • Glucomannan: 500 mg
  • Caffeine Anhydrous: 350 mg
  • Vitamin B6: 5 mg
  • Vitamin B12: 10 mcg
  • GTF Chromium: 100 mcg
  • Zinc: 10 mg
  • Piperine: 10 mg
  • Green Coffee Bean: 100 mg
  • Zinc: 10 mg

See a snapshot of the ingredients label below:

instant knockout ingredients label

While all of these ingredients are an important addition, the manufacturer states that 3 of them are critical to achieving the results you’re looking for.

They are: Green Tea Extract, Cayenne Pepper, and Glucomannan.

OMK reached out to Maggy Doherty, a registered dietitian and nutritionist, to get her take on this.

Here’s what she had to say about each of the primary ingredients in Instant Knockout:

Green Tea Extract

green tea extract benefits - instant knockout ingredient

Green tea extracts have been labeled as a “fat burner” and proposed to increase weight loss through its ability to increase your fat metabolism.1

The primary components in green tea extract that are believed to responsible for this are catechins and caffeine.

Catechins are a polyphenol that have anti-oxidant and antiviral properties; it is thought to stimulate fat oxidation through direct inhibition of catechol=0-methyltranferase, an enzyme that degrades norepinephrine.2

Caffeine may suppress appetite, increase energy expenditure, and elicit short-term thermogenic effects (aka: increasing your resting metabolic rate).

Clinical Trials of Green Tea Extract

A 2012 Cochrane review of 15 randomized controlled trials of at least 12 weeks duration comparing green tea preparation to control in overweight or obese adults found that the weight loss in adults who had taken a green tea preparation was small, not statistically significant, and not likely to be clinically 3

There is not enough evidence to determine if green tea can aid in weight loss, 4 however it MAY help with weight loss, but it likely will be a small amount (but, hey that’s better than none –right?!)

Other notable facts:

    • Additional benefits you may reap include enhanced metal alertness due to the caffeine 4
    • Green tea is safe for most adults in moderate amounts. 4

Be mindful that green tea extracts contain caffeine, which can cause insomnia, anxiety, irritability.

Cayenne Pepper

cayenne pepper benefits - instant knockout ingredient

Cayenne peppers may boost your metabolism through increasing your internal body temperature and in turn increasing your calorie burn.

This is attributed to the active compound in chili peppers, known as capsaicin, which makes them spicy or “hot”.

Clinical Trials of Cayenne Pepper

A 2014 meta-analysis of 19 studies looking at the effect of capsaicinoids (naturally occurring chemical in chili peppers), found that daily consumption of capsaicinoids may contribute to weight management through reduction in energy 5

Note: capsaicin is a type of capsaicinoid and the most common.


Where Glucomannan comes from. Image:

Glucomannan is a water-soluble fiber supplement made from the root of the konjac plant.

Fiber is an essential nutrient in weight loss because it takes longer for your body to digest, keeping you fuller for longer, which can lead to increased satiety and decreased calorie

Several randomized control trials did not find that glucomannan intake generates statistically significant weight

Although this one may not yet be supported for weight loss and fat burning, it has multiple benefits ranging from helping constipation, slowing absorption of sugar and cholesterol, and improving blood lipid and sugar 6

Instant Knockout Reviews

In general, reviews of Instant Knockout were very mixed. 

Some users report that it doesn’t work at all, and some say that it indeed did help with weight loss.

On the one hand, you have nothing but positive reviews on the Instant Knockout website.

Here’s an example of a review on their official website:

“I have been using it for three and a half months now and I can tell you this stuff is magical. I’m losing 2 – 2.5 kg (4.5 – 5.5 pounds) per month without any side effects and the results are constant month in, month out.  In a few months 15% body fat will be a reality. I’m so happy about that. And yes, I recommend Instant Knockout with all my heart to everyone serious about losing body fat.”

Note: You can read the full review on the Instant Knockout testimonials page here

instant knockout before and after picture - costas

Costas, Age: 53

Similarly, you’ll find some glowing reviews on the official Amazon listing, where many users rated it 5-stars:

instant knockout reviews on amazon

It appears that the vast majority of complaints surrounding Instant Knockout revolve around their return policy.

Some of the more common ones include sentiments like:

  • Misleading return policy
  • Very expensive
  • Bad customer service

On the flip side, we read several reports from actual users of Instant Knockout that reported weight loss of as much as 16 lbs. over the course of 4 months.

Commonly Asked Questions

How much caffeine is in Instant Knockout?

According to the manufacturer, Instant Knockout contains 350 mg of caffeine in a 4 pill serving.  

This is an extreme amount of caffeine to take at one time, so it’s recommended to start off with 1 or 2 capsules to assess your tolerance.

Are there any side effects?

Because of the large amount of caffeine content, side effects are certainly possible.

According to Healthline, consuming a large amount of caffeine can cause:

  • Rapid heart rate
  • Increased anxiety
  • Insomnia
  • High blood pressure
  • Fatigue
  • Digestive issues
  • Addiction

As noted earlier, it’s a good idea to start with the lowest dose possible to assess your tolerance level.

How do I take Instant Knockout?

The dosing requirements for Instant Knockout are 1 capsule, 4 times per day, spread out by around 2 – 3 hours.

It’s reportedly more effective if you take it on an empty stomach vs. with food.

This makes sense, because having food in your stomach will slow the absorption rate, potentially making it less effective.

Can I take it if I’m younger than 18?

This is not recommended.  Adolescents should avoid taking Instant Knockout for a variety of reasons, including:

  • Potential for stunted growth
  • Increased risk of side effects

If you’re under the age of 18, we do NOT recommend the use of Instant Knockout.

Is it safe?

All supplements, regardless of whatever category they are in, are unregulated by the FDA.

What this means is, the FDA does not routinely test supplements out to see if they actually contain what they say they do.

With that said, we couldn’t find any evidence to support the notion that Instant Knockout is in any way ‘dangerous’ or ‘unsafe’.

You may experience some side effects, but you will likely not experience any serious conditions as a result.

Pros And Cons


  • Works quickly to give you sustained energy levels
  • Uses all natural ingredients
  • Decent user reviews


  • Contains a large amount of caffeine
  • Isn’t FDA approved
  • Some users report no results

Where To Buy

You can buy Instant Knockout on their official website,

A one-month supply retails at approximately $59.00, making it relatively affordable when compared to many other supplements in this category.

They are also running a ‘Buy 3 bottles, Get 1 free” promotion, which reduces the price per bottle to just $46.25.

This includes free worldwide delivery, and is backed by a 90-day money back guarantee.


Obviously Instant Knockout is not some miracle pill.  It will not magically eliminate your fat, allowing you to sit on your phone all day and eat Cheese Its.

With that said, it definitely seems like it can help someone who is struggling to lose weight.

Along with a healthy diet and plenty of exercise, I would say it can realistically help you lose as much as 20% more than you would through diet and exercise alone.

Just keep in mind that it contains a very high dose of caffeine, which can cause all sorts of minor issues.

About Our Registered Dietitian, Maggy Doherty

Maggy Doherty, MS RD LD

Infatuated with all things food, Maggy Doherty is a Registered Dietitian from Dallas, Texas.

After competing as a UCLA student-athlete on the Women’s Diving team, earning her Master of Science in Nutrition at the University of Illinois at Chicago, and practicing as a clinical dietitian at Dallas’ Parkland Hospital, she is now the proud founder of Doherty Nutrition LLC.


  1. Position of the Academy of Nutrition and Dietetics: Interventions for the Treatment of Overweight and Obesity in Adults Raynor, Hollie A. et al. Journal of the Academy of Nutrition and Dietetics, Volume 116, Issue 1, 129 – 147
  2. Jeukendrup A., Randell R. Fat burners: Nutrition supplements that increase fat metabolism. Obes. Rev. 2011;12:841–851. doi: 10.1111/j.1467-789X.2011.00908.x.
  3. Jurgens TM, Whelan AM, Killian L, Doucette S, Kirk S, Foy E. Green tea for weight loss and weight maintenance in overweight or obese adults. Cochrane Database of Systematic Reviews 2012, Issue 12. Art. No.: CD008650. DOI: 1002/14651858.CD008650.pub2.
  4. National Center for Complementary and Integrative Health. National Institutes of Health: Green Tea. Septemeber 2016.
  5. Whiting S., Derbyshire E.J. and Tiwari B. (2014) Could capsaicinoids help to support weight management? A systematic review and meta-analysis of energy intake data Appetite 73, 183–188
  6. The Effects of Prebiotics and Substances with Prebiotic Properties on Metabolic and Inflammatory Biomarkers in Individuals with Type 2 Diabetes Mellitus: A Systematic Review Colantonio, Angela G. et al. Journal of the Academy of Nutrition and Dietetics, Volume 0, Issue 0

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General FAQ

How much caffeine is in Instant Knockout?

One serving of IKO contains 350 mg of caffeine anhydrous. It's recommended that you take the lowest possible dose first to assess your tolerance.

Can I buy Instant Knockout in stores?

According to several sources, Instant Knockout is not available in stores like GNC, Walmart, Walgreens, or CVS.

Is Instant Knockout legit?

Yes. They are a real company that sells a legitimate product. With that said, Instant Knockout is not some miracle pill that will magically shed the weight off. You still need to follow a proper diet and exercise routine to get the best results.

Is Instant Knockout FDA approved?

Like other supplements in its category, Instant Knockout is not FDA approved. It is, however, regulated by the FDA. This means that the FDA is responsible for taking action against any adulterated or misbranded dietary supplements once they reach the market.

Should I take Instant Knockout on an empty stomach?

The directions on the Instant Knockout label state that you should take 1 capsule immediately before breakfast, 1 capsule in between breakfast and lunch, 1 capsule 1 hour after lunch, and 1 capsule 1 hour before dinner.

Instant Knockout

Instant Knockout

4.5 out of 5 (87 Ratings)

Developed by a company called Roar Ambition, Instant Knockout is a ‘revolutionary shredding formula’ that claims to activate whole body burn. Originally developed for MMA fighters and professional boxers, their formula is reportedly based on scientific research and intended to Help burn stubborn fat deposits, Increase metabolism, Reduce hunger cravings and Increase energy levels.
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