Optimum Nutrition Thermo Cuts Fat Burner Review

Thermo Cuts Fat Burner

Thermo Cut by Optimum Nutrition is a fat burner supplement that claims to help you achieve the desired physique. It does this by increasing metabolic rate and by stimulating lipolysis in the body.

That sounds great, but does it really work? Read the below review to find out.


  • Contains some proven and natural thermogenic ingredients


  • Contains a proprietary blend
  • Lack of proven appetite suppressant ingredient in the formula
  • A box of 100 will not last you a month if you follow the daily dosage recommendation
  • Doesn’t promote constant fat burning throughout the day

Dosage – How to take Thermo Cuts fat burner

The company’s recommendation is to take 2 capsules of Thermo Cuts fat burner twice a day with a meal.

The most effective products spread their daily dosage between 3 or 4 servings per day to promote constant fat burning throughout the day. This is not the case with this product.

Furthermore, when you take a total of 4 capsules a day, a box of 100 will only last you 25 days.


The cost of Thermo Cuts fat burner will vary depending on the seller. A box of 120 capsules will cost you around $30 or £24 on the different supplement retailers’ website.

Shipping charges may also apply depending on the retailer. So check the terms and conditions when you are buying the product.

Where can I buy it?

Thermo Cuts fat burner is available from a number of online supplement retailers as well as from the company’s website.

Top 3 fat burners


Top 3 recommended fat burners


The formula of Thermo Cuts fat burner contains 300 mcg of Chromium and 2970 mg of the ThermoCuts proprietary blend.

Although the ingredients in the proprietary blend are visible on the label, their quantities are not displayed. This makes it difficult to see if the formula contains enough of an ingredient for it to be effective. On the flip side, it makes it impossible to know if it contains too much of an ingredient for it to be potentially harmful.


Caffeine and Green Tea Extract

The product contains caffeine and green tea extract, both of which are proven natural thermogenic ingredients. Research shows that daily caffeine intake of 250 to 350 mg is optimal for achieving great fat burning results. However, it is not advised on the label how much of this thermogenic is actually in the formula.

The amount may be so low that it does nothing to help fat burning or it may be so high that it can cause potential side effects. Similar to this, the amount of green tea is not advised on the label so we can’t tell whether the amount is sufficient for increased fat burning.

Guarana Extract

Guarana extract also appears as one of the ingredients in this fat burner product. It is a popular ingredient used in other fat burner products and some soft drinks due to its high caffeine content.

Similarly to caffeine, it is a thermogenic. However, unlike caffeine, the number of human studies that have focused on guarana and fat loss is limited. The ones out there have found contradicting results. Also, there is limited research looking into its potential long-term side effects.


Conjugated Linoleic Acid (CLA) is a type of fat. Our body is not able to produce this type of fat, so we get it from our diet.

A number of animal studies linked CLA to fat loss whilst still preserving muscle mass. These studies have revealed promising results. However, there are only a few human studies looking at the long-term effects of CLA. Not many human studies have investigated its potential side effects either.

Garcinia Cambogia

Garcinia Cambogia extract is also amongst the long list of ingredients of this formula. Its active ingredient is Hydroxycitric Acid (HCA). Manufacturers make claims that it helps curb appetite as well as inhibit fat production in the body.

Some research found supporting evidence, that taking Garcinia Cambogia can elevate serotonin levels in the body which in turn decreases appetite. However, there is need for additional research to further investigate these claims to provide more robust data confirming its properties as a weight loss aid.


L-Carnitine is an amino acid that plays a vital role in energy production in the body. Some studies have shown that when combined with low-intensity exercise, L-carnitine helps the body to use more of the fat stores rather than carbohydrates as a source of energy. This is great news. However, the effects of L-carnitine seem to depend on the intensity of the exercise.

Find out what really works and what to avoid on

– Best and worst fat burner ingredients –

Potential side effects of Thermo Cuts fat burner

The most common side effects of Thermo Cuts fat burner can be caused by the caffeine contained in this product. So if you are sensitive or allergic to caffeine this product may not be for you.

As Garcinia Cambogia has been shown to elevate serotonin levels, this fat burner ingredient can cause potential problems when people are taking it with certain antidepressant drugs.

Final Verdict on Thermo Cuts fat burner

Based on the above review, my rating is a lower than average 2 out of 5 stars for Optimum Nutrition Thermo Cuts.

The product contains caffeine as well as green tea extract as effective, natural thermogenic ingredients. Both are great fat burners and have been supported by a number of research studies especially when used together.

However, Thermo Cuts fat burner contains a proprietary blend where only the ingredients are visible, but not their amounts. This makes it difficult to judge whether the amounts are sufficient to be effective or if they are too high and may cause unwanted side effects.

Adding to this, there is no proven, natural appetite suppressant in the formula. The product is only a one-sided thermogenic fat burner.

Finally, the dosage of 2 times 2 capsules per day, means that there is no even supply of ingredients throughout the day.

Although the product has a competitive price, the proprietary blend and the lack of proven and effective ingredients make this fat burner less attractive than other competitor products.

Check out my #1 recommended fat burner supplement Instant Knockout

Instant Knockout One Box

  • A great natural product with an impressive list of ingredients
  • Highly effective thermogenic ingredients combined with proven and natural appetite suppressant ingredients
  • Helps you cut more fat and achieve impressive results
  • Gives you a great boost of energy before workouts


Read the full review on Instant Knockout


Supplements should never be taken in place of a healthy diet and regular physical activity. You should always aim to get these two key pillars right first.

If you need some help with exercise, you can check out my post on Muscle Building and Fat Burning Exercises.

Alternatively, you might want to invest in an online workout guide like Boss Workouts or hire a personal trainer if you prefer that.

You can also check out my post on healthy meal ideas in aid of weight loss if you need some inspiration.