Thermogenics And Calorie Burning: Is It The Caffeine?

Thermogenics & Calorie Burning: Is It The Caffeine?

Pick up any thermogenic product and I am willing to bet that it contains caffeine. Or maybe it contains mate, guarana, kola nut, cacao or green, black or white tea, or a combination of any of these ingredients (all of which are botanical sources of caffeine)¹.

Caffeine (naturally occurring or added synthetic caffeine^2,3,4) or caffeine-containing botanicals, are often formulated into weight loss products because caffeine increases both lipolysis (the breakdown of fat) and thermogenesis (calorie burning) for a period of time after ingestion.

Back in the day when ephedra dawned supplement store shelves, figure competitors and bodybuilders quickly discovered that the research-backed combination of ephedra + caffeine⁵ helped them shed any fat hiding their muscles prior to competition. Now that ephedra is pretty much out of the picture we are left with caffeine.

Caffeine plus a wide array of other ingredients that haven't been shown to do a whole lot by themselves but they sound good on the back of a bottle and may work synergistically with caffeine. And, there are a plethora of acute studies, indicating that immediately post-consumption, caffeine containing products temporarily increase thermogenesis^{6,7,8,9,10,11}.

However, there are also a few studies that have been recently published or presented as abstracts indicating that products containing caffeine may also augment weight loss efforts if consumed daily. That's huge. And it's new research.

EliteFx's Celsius Vs Diet Coke

EliteFx, the makers of the Celsius^TM have dumped some money into research trials examining whether it can hold it's own next to the various weight loss supplements on store shelves. This product contains approximately 200mg caffeine in the form of guarana, green tea leaf (containing 10% ECGC) and ginger root along with B vitamins, vitamin C and calcium.

In one of the first studies on this beverage, they compared it to Diet Coke® (about 45 mg caffeine). Twenty college students came into the lab, drank either the Diet Coke® or Celsius^TM and the researchers measured the change in their metabolism over a 3-hour period. Then they did the exact same study again and switched the groups so the college kids drinking the Celsius^TM got the Diet Coke® and vice versa.

After looking at the results from both trials, the researchers found that Diet Coke® did raise metabolism just a little but, Celsius^TM significantly raised metabolism for the three hours post-consumption¹². It could be the caffeine or it could be the caffeine + green tea, either way, it seems to work.

Green tea has two thermogenic components, caffeine and EGCG. Though researchers aren't completely sure how green tea works, they know the catechin polyphenols (like EGCG), help boost circulating norepinephrine which increases the breakdown of stored fat and stored carbohydrates¹³.

After the first few studies looking at what affect Celsius^TM had on metabolism right after consumption, they examined whether it would help increase weight and fat loss over time (28 days).

In this study they took sedentary, slightly overweight men and women and put them on a supervised endurance and resistance training program. One group consumed the new product 15 minutes prior to working out on training days and whenever they wanted to on non-training days.

The endurance and resistance training program worked because both groups lost fat (that's a good thing). However, only the Celsius^TM group saw a significant change in fat free mass (muscle) and this group also lost a significantly greater amount of fat mass¹⁴. So it seems that consuming this beverage daily may augment the positive physique changes associated with an endurance and resistance training program.

Caffeine From Coffee

If you prefer coffee, a coffee company called Javalution has created functional coffees including JavaFit Diet and JavaFit Energy Extreme. The first version of JavaFit Energy Extreme (450 mg caffeine, 360 mg citrus aurantium, 1200 mg garcinia cambogia, 225 mcg chromium polynicotinate) may have had you jumping through the roof if you were not used to consuming that much caffeine (a Starbucks venti Caffe Mocha made with espresso has 180 mg caffeine by comparison), but it did increase calorie burn post consumption and in comparison to regular coffee¹⁵.

The current version of JavaFit Energy Extreme (a different formula than the aforementioned study; it contains just 62 mg added caffeine, green tea extracts, niacin, garcinia cambogia) has also been found to increase calorie burn, for up to 3 hours, post consumption¹⁶. Look for additional research coming out soon on JavaFit Diet Plus and weight and fat loss over time.

Caffeine From Supplements

As far as supplements, a particular supplement containing tyrosine, capsaicin, catechines and caffeine (unknown quantity) was found to slightly increase fat loss in obese subjects on a low caloric diet over a period of 8 weeks¹⁷. All of these studies mentioned here show promise for caffeine and thermogenic supplements to enhance weight loss and fat loss.

A few interesting tidbits about caffeine:

• Within 45 minutes after ingestion, caffeine is completely absorbed by the body¹⁸.
• The total time it takes to eliminate caffeine completely depends upon many factors such as age and various aspects of one's health. In healthy individuals at least half of the total caffeine consumed at a given time is eliminated in approximately 3 to 4 hours¹⁹.
• We adapt to the amount of caffeine we regularly consume by increasing the number of receptor sites that caffeine binds to in our central nervous system so we end up needing more caffeine over time to achieve the same stimulatory affect we felt when we initially started taking caffeine²⁰.

The Central Nervous System

The human central nervous system consists of the brain and spinal cord. These lie in the midline of the body and are protected by the skull and vertebrae respectively.

This collection of billions of neurons is arguably the most complex object known.

The central nervous system along with the peripheral nervous system comprise a primary division of controls that command all physical activities of a human.

Neurons of the central nervous system affect consciousness and mental activity while spinal extensions of central nervous system neuron pathways affect skeletal muscles and organs in the body.

• If habitual caffeine consumers reduce their caffeine intake, they get headaches, may be irritable and may initially feel like they aren't concentrating as well. Once the number of receptor sites decreases, these withdrawal symptoms will decrease as well²⁰.

There are a number of caffeine containing products on the market including drinks such as Celsius^TM (approximately 200 mg caffeine in a 12 oz bottle) and JavaFit coffee and, if you prefer to take your caffeine on the run in pill form, Lean System 7 by Isatori, Hot-Rox Extreme and Hydroxycut are just a few of the choices you have.

Conclusion

Though caffeine may help augment your weight loss efforts, don't expect to go from a size 22 to a size 4 by increasing your caffeine intake alone. And, though caffeine is considered Generally Recognized as Safe (GRAS)²¹ and has been consumed for hundreds of years, every person's tolerance to caffeine differs, and, caffeine may be unsafe for some people when consumed in high doses, especially over long periods of time.

Those with any particular health problems should talk to their physician first before bumping up their caffeine intake. And if you are on any particular medicine that may interact with caffeine (such as diethylpropion, phentermine, pseudoephedrine, epinephrine^26,27, clozapine²⁸, riluzole²⁹) also talk to your doctor first.

Doses of 250 to 300 mg or more per day may result in other unwelcome health problems. Pregnant women should definitely keep their caffeine consumption below 300 mg per day^30,31. And like anything (including water in the absence of adequate electrolytes), too much isn't good.

Ingesting approximately 10 to 14 grams of caffeine (150-200 mg/kg body weight) can cause death.³² But again, normal caffeine consumption shouldn't harm a healthy person, and it make even make you concentrate better, stay awake during a boring meeting and possibly, help you show off those abs you've worked so hard for.

References

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