B-phenylethylamine (PEA) is a popular ingredient in many weight loss formulas that is aggressively marketed as a potent amphetamine-like substance. PEA is associated with stimulation of various neurotransmitters in the brain that influence emotions such as euphoria and alertness. Many weight loss products claim that taking PEA supplements will increase normal brain concentrations of PEA. However it is well established in the literature that it is extensively and rapidly metabolized by the enzyme monoamine oxidase (MAO). Many weight loss formulas with PEA will therefore add ingredients that allegedly inhibit MAO. But studies actually show the combination of PEA administration and partial or complete pharmaceutical inhibition of MAO does not produce psychomotor-stimulant effects or stimulant-like behavior. The truth is if PEA was a legitimate "amphetamine like" substance that produced a powerful stimulant effect, we would see products with just PEA as the only ingredient. But the fact is, such products would yield no noticeable effect whatsoever and therefore marketers are forced to combine it with caffeine, yohimbe, and other ingredients that will have some noticeable effect. Thus, the PEA is only included in those products as a marketing twist to dress up the formulations and make them look more sophisticated. The bottom line on PEA is that the science is quite conclusive on the fact that it has no beneficial effect whatsoever. It is a complete waste of money. Now that we cleared that up, let's focus on the newest, proven effective fat-burning, metabolism-boosting additions that any top quality thermogenic formula should contain.
Green Coffee Extract
One of the newest thermogenic ingredients to hit the market, green coffee extract is already finding its way into some of the more advanced formulations. And for good reason. Both green coffee extract and its major phenolic compound chlorogenic acid have shown significant thermogenic fat-burning effects, as well as other health promoting actions. In one recent clinical study, for example, its benefits were more than evident as researchers who conducted the study found green coffee extract actually prevented weight gain and fat accumulation. The effect is likely due to a combination of the caffeine, chlorogenic acid, and other polyphenolic compounds, with the powerful antioxidant activities in the green coffee extract. Chlorogenic acid appears to target fat stores in the liver, as opposed to adipose triglyceride stores, by up-regulating one of the rate limiting enzymes in fat oxidation, carnitine palmitoyl transferase. Chlorogenic acid contains a compound called ferulic acid, which has been shown to stimulate nitric oxide bioavailability, and have a positive effect on vascular dilation and blood pressure. The science behind this compound is accumulating both positive data and acceptance as a solid contributor to the thermogenic category. In fact, another new study, just released, showed that coffee enriched with chlorogenic acid, resulted in a significant decrease in glucose absorption and a stunning, three-fold greater weight loss compared to a group receiving instant coffee. Recap:
- Green coffee extract is a clinically tested, thermogenic fat loss agent.
- The major compound in green coffee is chlorogenic acid, which is metabolized to ferulic acid in the liver.
- Green coffee extract also contains caffeine, a potent stimulator of norepinephrine and thermogenesis.
- A recent study showed green coffee extract helps prevent fat accumulation and body weight gain.
- A recent randomized human study showed a three-fold greater weight loss in subjects receiving coffee enriched with chlorogenic acid.
In the last few years, the herb Macuna pruriens has gained revered status in the bodybuilding arena because of its naturally occurring compound called L-Dopa. L-Dopa is a neurotransmitter that has a variety of functions in the brain among which is the stimulation of growth hormone (GH). This GH stimulation is a rare attribute prized by bodybuilders and baby boomers alike. Because Macuna may help correct hormonal imbalances, and in particular enhance GH secretion, there is potential value for significantly promoting fat breakdown and muscle growth, simultaneously. Growth hormone is a peptide hormone secreted from the anterior pituitary in the brain. In skeletal muscle, GH promotes a positive protein balance by increasing protein synthesis and possibly inhibiting protein breakdown. In adipose tissue, GH increases lipolysis (fat breakdown) and dramatically decreases lipogenesis (fat synthesis). Thus, GH serves as a very powerful nutrient-partitioning agent, which is music to the ears of anyone working to transform their physiques at any level, from top pros to the casual fitness buff. Ultimately, Macuna pruriens, especially when it is of high quality and standardized for 15% L-Dopa, represents a natural and powerful way to achieve elevated levels of growth hormone. Recap:
- Macuna seed powder extract is a significant source of L-Dopa. Macuna pruriens significantly elevates plasma L-Dopa levels.
- Studies have shown Macuna pruriens also has potent antioxidant effects.
- Research indicates that a high quality Macuna pruriens standardized for 15% L-Dopa, yields elevated levels of growth hormone and enhanced fat loss potential.
Vinpocetine has more recently earned a hot spot in quality thermogenic formulas, due to its ability to increase norepinephrine, and boost metabolism. Vinpocetine is derived from the leaves of the Lesser Periwinkle (Vinca minor) native to Europe. It has been primarily studied clinically in patients with cognitive decline or to treat symptoms of acute stroke, motor disorders, and dizziness. The precise mode of action is not exactly known, though it has been postulated, and basically accepted, that this potent compound works to help inhibit phosphodiesterase, and therefore, potentiate the effects of other thermogenics that work through stimulation of cAMP in cells. In addition, vinpocetine has been shown to inhibit a cyclic GMP phosphodiesterase, and it is speculated that this inhibition enhances cyclic GMP levels in the vascular smooth muscle, leading to reduced resistance of cerebral vessels and increase of cerebral flow. There is also evidence that vinpocetine may increase norepinephrine directly. In one experiment, vinpocetine increased both the resting and the nerve stimulation-evoked release of norepinephrine from blood vessels. And finally, in some studies, vinpocetine has demonstrated antioxidant activity equivalent to that of vitamin E. Stated more simply, this valuable bioactive contributes to any thermogenic formula by basically providing enhanced brain cognition and function, norepinephrine release and improved mood. Recap:
- Vinpocetine is a potent inhibitor of phosphodiesterase, which may spur a synergy with other thermogenics. It is a valuable antioxidant.
- Numerous studies show enhanced cerebral blood flow and consistent improvements in cognitive performance with vinpocetine supplementation.
- Vinpocetine also directly increases norepinephrine.
Because of oolong's unique bioactive profile, and because it delivers a different spectrum of catechins than green tea, some of the best products use the two teas together in their formulations. That's why oolong tea is more and more becoming an effective and preferred ingredient in some of the more advanced thermogenics on the market. Aside from wonderful water, the most popular beverage consumed worldwide is Camellia sinensis, more commonly known as tea. About three-fourths of all tea produced is black tea (77%), the remaining forms are either green (21%) or oolong tea (2%). All three variations are of the same plant, with the differences occurring during the processing of the tea leaves, which impacts the levels of bioactive flavonoids. Black tea has the least amount of flavonoids because it is oxidized enzymatically during processing, thus giving it the black appearance and a more roasted flavor. In contrast, green tea is heated and dried to avoid enzymatic oxidation altogether, while oolong tea is semi-fermented, which significantly reduces the level of oxidation. Representing only a small fraction of the total amount of tea produced, the oolong variety contains a broad spectrum of polyphenols and catechins. In terms of total catechins, oolong tea is on par with green tea, while actually outperforming the other forms in terms of total caffeine, phenolic compounds and anti-mutagenic activity. Researchers are quickly learning that oolong tea delivers a wide array of benefits and are just scratching the surface of this amazing plant's full potential. For certain, it is an excellent addition to any thermogenic product.
- Oolong tea is a very good source of caffeine and several bioactive polyphenols.
- The catechin profile of oolong tea is different than green tea.
- Because oolong has a different catechin profile than green tea, the best products use the two teas together.
- The catechins in oolong have shown effects on thermogenesis and weight loss.
Caralluma fimbriata is a new addition to the category that appears to be on the cutting edge of fat-loss technology. This edible plant has been known and consumed throughout India for hundreds of years as an appetite suppressant, thirst quencher and endurance enhancer. Two major clinical trials have been conducted on this powerful ingredient, and both showed highly successful outcomes. In a randomized, placebo controlled study, 62 overweight men and women either consumed a Caralluma fimbriata extract (1 g per day) or a placebo (maltodextrin) for 60 days. The results surpassed all expectations as the weight loss was actually two-fold greater in the Caralluma group (-2 vs -1 kg), while the percent of body-fat was reduced to a greater extent as well. In addition, subjective ratings of hunger were reduced by a remarkable 20% in the Caralluma group, which corresponded to a significant decrease in caloric intake. In yet another clinical study, this one over a duration of four-weeks, the preliminary findings provided further support for its tremendous efficacy. The study showed subjects who supplemented with 500 mg of Caralluma fimbriata extract before each meal, had consistently greater weight loss than placebo. In fact, over half the subjects in the Caralluma group lost more than 6 pounds in that 4-week period. Based on these clinical studies alone, it has become abundantly clear that this unusual compound offers exciting new potential as a true and powerful appetite suppressant and body-fat reducer. If it works this well alone, imagine what it can do when included in a state-of-the-art formulation of other key thermogenic compounds, all working synergistically, via multiple pathways. It's fair to say that Caralluma is quickly earning a place as one of the few truly effective weight loss compounds available today.
- Caralluma fimbriata is an edible plant native to India, used for centuries as an appetite suppressant and performance enhancer.
- Caralluma contains a variety of phytochemicals including pregnane glycosides, flavone glycosides, megastigmane glycosides, bitter principles, and saponins.
- Two recent clinical studies show Caralluma to have consistent effectiveness as an appetite suppressant and weight-loss agent.
Like most fruit, raspberries contain a delicious array of potent compounds that contribute to health and performance. Chief among them, we are discovering, are its significant benefits to weight loss. The key compound from raspberries, called Razberi-K (RK), is yet another fairly new addition to this important category. Also known and represented as (4-(4-hydroxyphenyl) butain-2-one in the literature, this aromatic compound has been shown to work through two distinct mechanisms: decreasing absorption of dietary fat, and stimulating lipolysis (the breakdown of fats by the enzyme lipase). A look at the structure of RK provides some clues as to its fat-fighting benefits. Chemically, it is very similar to capsaicin, the major pungent principle in hot peppers. Several studies have reported that capsaicin acutely increases energy expenditure, reduces food intake, enhances fat oxidation, and decreases body fat. RK is also similar in structure to synephrine, a naturally occurring alkaloid found in the fruit of Citrus aurantium. Synephrine acts on cells through adrenergic receptors, specifically on beta-3 adrenergic receptors and maybe alpha-1 receptors, which promote fat breakdown. Based on its similarities to those two compounds and its unique structural features, researchers hypothesized it would and should have potent effects on obesity and lipid metabolism. Japanese researchers recently performed experiments detailing the anti-obesity effects of RK. The results showed that it was effective in preventing obesity in response to a high calorie diet. RK specifically promoted increased norepinephrine-induced fat breakdown, enhanced thermogenesis, and inhibited absorption of dietary fat. Together, these effects contributed to a profound reduction in whole body fat as well as fat in visceral adipose tissue and the liver. Due to its unique chemical structure and multiple mechanisms of action, RK looks very promising as a fat-loss agent. Here again is another fairly new compound to the category that has the real potential to deliver significant benefits.
- Chemically RK is similar to capsaicin and synephrine, known thermogenics.
- RK promotes breakdown of fat in adipocytes.
- Stimulates thermogenesis and inhibits absorption of fat.
- RK specifically promoted increased norepinephrine-induced fat breakdown and inhibited absorption of dietary fat.
- Recent work showed RK results in reductions in whole body fat, particularly from visceral fat.
Green Tea Extract
Arguably, the most popular thermogenic compound is green tea extract, and for good reason. A large body of work exists supporting positive effects of green tea on a wide range of biological effects that i mprove health and weight management. Although green tea does contain a wide variety of compounds, most research has focused on EGCG as the predominant active ingredient that is responsible for the thermogenic, antioxidant and anti-carcinogenic effects. A few years back, a major green tea study designed to examine thermogenesis and fat oxidation kicked off the obsession with this thermogenic supplement. Ten healthy men with a wide range of body fat consumed either 1) green tea extract containing 150 mg of caffeine and 270 mg epigallocatechin gallate (EGCG), 2) 150 mg of caffeine, or 3) a placebo. The green tea extract was shown to increase 24-hour metabolic rate by 4% compared to a placebo. This amounted to an increase in energy expenditure of 80 kcal/day. Furthermore, it caused a shift to greater fat oxidation over carbohydrate oxidation and also a greater urinary excretion of norepinephrine over 24 hours during treatment with green tea extract. And to top off these excellent results, there were no adverse side effects including no differences between treatments in heart rate. In fairly general terms, here is how it works. Green tea is particularly rich in the flavonoids known as catechins. Catechins have a wide range of biological effects, but perhaps most pertinent to thermogenesis is that catechins inhibit catechol O-methyltransferase (COMT), the enzyme that breaks down norepinephrine. Norepinephrine is a hormone, that when released, increases cellular levels of cyclic AMP (cAMP), which in turn, increases metabolic rate and breakdown of fat in cells. Green tea also contains caffeine, which inhibits the enzyme phosphodiesterase. Phosphodiesterase breaks down cAMP in cells and thus can dampen the stimulatory effects of norepinephrine. Simply stated, green tea works through the interaction of catechins and caffeine. Other mechanisms of action that make green tea extract attractive as a weight loss agent have been identified. German researchers showed that 300 mg of EGCG caused a shift in energy utilization from carbohydrate to fat oxidation. The effect was more pronounced after ingestion of a meal, which provides a plausible mechanism to explain the anti-obesity effects of green tea. The acute benefits of green tea were further documented in yet another significantly remarkable study. After 12 weeks of green tea supplementation (containing 690 mg catechins/day), men had two-fold greater weight loss (-2.4 vs -1.3 kg) and fat loss (-1.4 vs -0.7 kg) compared to placebo. Additionally, compared to placebo, green tea had a four-fold greater effect on reductions in subcutaneous and visceral fat in the abdomen. The study shows that green tea is an effective method for losing fat, particularly in the mid-section. Collectively, these studies provide strong evidence that green tea contains bioactive and bioavailable substances that can help in the management of body-fat through multiple mechanisms. Importantly, while green tea appears to work primarily through the sympathetic nervous system hormone norepinephrine, it is distinct from other similar substances that act through adrenergic receptors, in that green tea does not have adverse cardiovascular effects.
- Green tea extract is a rich source of the bioactive polyphenol EGCG.
- EGCG has been linked to a multitude of health effects in cell culture, animal studies and human clinical trials.
- EGCG inhibits breakdown of norepinephrine and acutely stimulates thermogenesis and fat oxidation.
- Standardized green tea is a proven metabolism booster.
- EGCG has been shown to cause greater fat loss in weight loss studies.
Caffeine has been a staple in coffee, tea, chocolate and supplements for so long, that it'd be difficult to find an adult who has never enjoyed its benefits. Even with that, it has recently garnered even greater status as a true thermogenic powerhouse. Perhaps more than any other compound of its kind, there is a solid base of research supporting multiple positive metabolic effects of caffeine. Several studies have shown acute ingestion increases thermogenesis and in a dose-dependent manner. In one recent study, caloric expenditure was increased 13% after intake of a single dose of caffeine. There was also a marked increase in fat breakdown and fat oxidation after caffeine. In addition to promoting higher fat oxidation in the resting state, caffeine intake also increases the use of fat during exercise, an effect that enhances performance. Caffeine has also been shown to decrease caloric intake. Needless to say, the science behind this unassuming compound is very impressive. And it's good news for anyone looking to lean out. Caffeine works to promote thermogenesis and fat breakdown and utilization through a complex network. Many of the metabolic effects are mediated through enhanced activity of the sympathetic nervous system. It affects metabolism by other means as well, such as working to increase epinephrine (also known as adrenalin) levels. Epinephrine, in turn, is a potent activator of cAMP in cells that upregulates hormone sensitive lipase, the main hormone responsible for breaking down fat. In cells, caffeine also prevents the breakdown of cAMP by inhibiting the enzyme phosphodiesterase. In this way caffeine and epinephrine synergistically work together to promote fat breakdown. Another real reason to get amped about this thermogenic is there is no evidence that caffeine ingestion before exercise leads to dehydration, ion imbalance, or any other adverse effects. Despite popular opinion, overwhelming research suggests that moderate coffee and caffeine consumption causes no adverse health effects. Thus, it is reasonable to conclude that regular caffeine use, particularly in a controlled, standardized supplement form would be very beneficial for weight regulation, especially if used in combination with other thermogenics.
- Caffeine is a central nervous stimulant.
- Caffeine stimulates release of norepinephrine, fat breakdown, and fat utilization at rest and during exercise.
- Caffeine acutely stimulates thermogenesis, and reduces caloric intake.
- Caffeine decreases perception of effort during exercise and improves exercise capacity in many studies.
- Overwhelming research suggests that moderate caffeine consumption causes no adverse health effects
Taken individually these ingredients can offer real effectiveness. Any quality product in the thermogenic category should have at least one or two of these ingredients as its scientific backbone for weight-loss efficacy. In fact, there are few solid formulas in this category that do not utilize one or more of these ingredients. However, since they each seem to work through a different mechanism, using several of them in combination with each other may represent the ultimate synergistic supplement strategy for maximizing weight-loss.
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