Thermo Cuts is a food supplement manufactured by a world-renowned company Optimum Nutrition.
Priced $30 per bottle, it is designed to:
- Accelerate your metabolism
- Help turn fats into energy
- Fight sugar cravings
The formula is plant-based and includes the likes of Guarana, Green Tea, and some spices to help with thermogenesis.
But how well will this fat burner work for you?
We analyze its formula with a fine-tooth comb to find out how effective and safe it is.
How Does it Work?
Thermo Cuts consists of compounds that are known to speed up the metabolism and thus help with the conversion of fatty acids into energy when you’re training.
Cayenne Pepper in Thermo Cuts works by boosting core body temperature, which is helpful for fat burning.
Some other ingredients reportedly act on the body’s neurotransmitter release which can influence appetite.
Sounds promising – but does it really work? Let’s check the ingredients themselves.
Thermo Cuts’ formula is fully transparent, which allows us to see the doses of its ingredients inside.
It has three great ingredients – green tea extract, caffeine and cayenne pepper.
The rest of the formula, however, doesn’t look overly convincing.
Thermo Cuts has decided to use a number of unproven ingredients, along with adding more caffeine through Guarana – increasing the risk of side effects.
Here’s a closer look at each ingredient in this fat burner.
1. N-Acetyl L-Carnitine (750mg)
L-Carnitine is an amino acid naturally made by your body and found in some foods. It’s a popular type of ingredient in fat burner supplements.
However, the science doesn’t agree with the hype this particular ingredient has been getting. Isolated studies haven’t shown promising results in terms of weight loss.
The studies that did see success with carnitine dosed it much higher than what’s found in Thermo Cuts. 
That being said, Carnitine can offer some benefits outside of fat loss. Even at lower doses.
The “Acetyl” part means Carnitine is able to cross your blood-brain barrier, making it effective at improving cognition and mental clarity.
2. Caffeine (200mg)
The most widely used stimulant in the world, caffeine, is highly effective at putting your body in “fight or flight” mode.
When the body is in this kind of state, it releases hormones such as epinephrine and dopamine which improve focus, energy levels and power output. 
Interestingly, this has a knock-on effect on fat burning as the metabolism has to work harder in order to keep up with the increased energy demands of the body.
3. Green Tea Extract (150mg)
Green Tea is a highly popular drink among athletes and fitness enthusiasts. It’s been found that when paired with caffeine, green tea can enhance your metabolism beyond what caffeine does alone.
More specifically, green tea has the potential to increase your metabolism to burn an extra 200kcal per day without exercise. However, optimal doses of green tea are between 300-500mg per day. 
If you’re taking one daily serving of Optimum Nutrition Thermo Cuts, it will provide you with only 150mg of green tea per day. Doubling down on the servings can lead to side effects due to other ingredients in Thermo Cuts that are high in caffeine.
4. Guarana Extract (100mg)
Guarana is a powerful stimulant. Its seeds have more than double the caffeine than what you’ll find in regular coffee seeds.
In addition, Guarana seeds contain some other beneficial compounds such as Theobromine, which have stimulatory effects of their own.
The only problem is that there’s already a lot of caffeine in Optimum Nutrition Thermo Cuts. For anyone who’s intolerant to stimulants’ aggressive nature, this will be too much.
5. Thiamin (Vitamin B1) (2mg)
Vitamin B1 is an essential vitamin that’s needed for glucose production. For healthy people who eat a varied diet, this nutrient doesn’t offer much benefit as it’s already found in plenty of foods. 
However, alcoholics or people who suffer from chronically high blood sugar levels could need more of it to maintain healthy body composition.
6. Riboflavin (B2) (2.2mg)
Riboflavin is another essential B vitamin. It plays different important roles in your body, such as ensuring optimal enzyme function. 
Supplementing it doesn’t have much of an effect on fat loss, however.
It can only benefit people who’re deficient in it, such as vegans, mainly by supporting cardiovascular function.
7. Vitamin B6 (2.4mg)
Getting enough vitamin B6 through your diet is the best way to reap many of its small benefits.
Supplementation is often unnecessary as it’s found in many different foods, including plants.
8. Zinc (6mg)
Zinc is an essential dietary mineral that helps to regulate your hormone levels and other vital bodily functions. 
It’s not typically found in fat burner formulas because supplementing it doesn’t influence weight loss to the same degree as ingredients like cayenne pepper.
Additionally, its dose is low compared to what we’re used to seeing in other supplements.
9. Murraya Koenigii (300mg)
Also known as Curry Leaf Tree, this ingredient has a long history of use in traditional Indian medicine.
People most commonly use it to induce weight loss, but does it really work?
Some of the evidence shows that it helps lower blood sugar levels. In other words, it doesn’t help you lose weight but it might help stop you from gaining it.
Murraya Koenigii’s biggest benefit is that it can protect your cells from damage. The leaves are rich in antioxidants that scavenge free radicals and prevent them from causing inflammation in your body. 
10. Cayenne Pepper Extract (40mg)
Cayenne Pepper’s benefits stem from its active ingredient “capsaicin” which is known for increasing core body temperature.
It improves blood circulation in your body and increases the basal metabolic rate.  However, the dose needed to achieve these effects is somewhere around 100mg.
11. Black Pepper Extract (10mg)
Containing the active compound piperine, black pepper extract is one of the best herbal bioavailability enhancers.
While it doesn’t necessarily promote weight loss, it’s useful for boosting the absorption of other ingredients in your body – making them more effective. 
This wouldn’t be much of a concern if Optimum Nutrition Thermo Cuts didn’t have so many stimulants in it. Potentiating them only increases the risk of side effects.
12. Wakame Extract (40mg)
Wakame is an edible seaweed from Japan and Korea. It’s low in calories but high in nutrients that contribute to increased energy levels and overall health. It has no significant influence on weight loss, however.
How to Take Optimum Nutrition Thermo Cuts?
Optimum Nutrition Thermo Cuts dosage is 2 capsules, twice per day. Since it contains high amounts of caffeine, you should never take it too close to bedtime as it can interfere with your sleep.
The main risk with Thermo Cuts is its high caffeine dose. Combining multiple stimulants is rarely a good idea, especially if you add caffeine from other sources such as coffee or energy drinks.
Too much caffeine is known to cause :
- Anxiety Episodes
- Heart Palpitations
- High Blood Pressure
That brings us to the end of our Optimum Nutrition Thermo Cuts review.
It’s a supplement that caters to a very small audience – those that can tolerate its harsh effects and don’t mind consuming high amounts of caffeine.
It has Guarana and Green Tea which help to boost your focus and energy levels, and can make it easier to see your goals through. However, the lack of a better appetite suppressant and a few other ingredients means it doesn’t score as high as it would.
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