Top 10 Brown Fat, Thermogenic, Fat Burners
By Robert Schinetsky
Fat burners are among the most popular dietary supplements lining store shelves. When you take into consideration that approximately 70% of the population is either overweight or obese and that at any given time, 40% of the population is dieting, it’s easy to see why fat burners and thermogenics are in such high demand.
Unfortunately, the vast majority of fat burners you’ll encounter pack a lot more bark than bite, meaning that by and large the typical weight-loss supplement you see on the store shelf talks a big game, but does next to nothing in terms of actually burning excess body fat.
In fact, most thermogenics are nothing more than glorified stim bombs, and instead of burning fat, boosting metabolism or suppressing appetite, they leave you feeling overstimulated, jittery and anxious.
Suffice it to say that conventional fat burners are by and large a sham, but they don’t have to be...if you know what ingredients to look for.
Ahead, we’ll discuss the top 10 thermogenic and brown fat-activating compounds, as demonstrated by science.
But before we get there, let’s briefly review the two main types of adipose tissue found in the body, white fat and brown fat.
A BRIEF PRIMER ON BROWN ADIPOSE TISSUE (BROWN FAT)
Researchers have long known that the human body contains two specific, yet very different types of fat cells:
- White fat – relatively inert form of stored energy composed of single, large fat droplet.
- Brown fat – cells composed of many small droplets loaded with mitochondria. Brown fat is more metabolically active, burns calories at a higher rate than white fat, and helps maintain core temperature when exposed to cold weather.
Based on this information, it stands to reason that if it’s possible to convert more white fat to brown fat or stimulate the existing brown fat, a greater amount of calories would be converted into heat, reducing overall body fat, bodyweight and waistlines in the process. In fact, obesity researchers are exploring ways to increase BAT activity as a safe and effective means to combat the increasing obesity crisis.
However, complicating this issue is the fact that BAT activity tends to decline with age, which is one of the reasons individuals more easily accumulate extra weight as the years go by.
With that said, let’s get to the top 10 supplements you can use to help stimulate brown adipose tissue and ramp up thermogenesis.
TOP 10 THERMOGENIC & FAT BURNING SUPPLEMENTS
What can be said about caffeine that hasn’t already been stated 1,000 times before?
It is a powerful central nervous stimulant well-documented to increase energy, alertness, wakefulness, exercise performance and mental focus. It also helps reduce appetite and boost metabolism.
And, it can be found just about everywhere these days, from pre-workouts to weight-loss support supplements to even peanut butter and protein powder.
Research has shown that consuming just 100mg of caffeine (about the amount you get in an 8 oz cup of strong drip coffee) can boost thermogenesis and increase energy expenditure up to 100 calories per day. More recent research has shown when caffeine is combined with other common fat-burning supplements, the dose needed is as low as 77mg.
Now, you might be wondering if these metabolism-boosting effects caffeine dwindle with continued use – apparently not, according to some research. In fact, studies have shown that even in habitual caffeine users (~100-200mg per day), ingesting a 100mg dose of the consummate stimulant resulted in a significant thermogenic effect lasting over 3 hours.
Naturally occurring in Citrus Aurantium (bitter orange), p-synephrine is a fat-burning alkaloid widely used to help boost metabolism and rid the body of excess weight. The manner in which p-synephrine encourages fat loss is due to its affinity for beta-3 adrenergic receptors found in brown fat.
Without getting too mired down in human biology, fat cells have two types of receptors that affect fat loss when stimulated. Specifically,
- Alpha receptors – hinder fat burning by turning “off” lipolysis (the release of stored fatty acids into the bloodstream)
- Beta receptors – encourage fat burning as they trigger lipolysis when activated
Research has shown that p-synephrine has high affinity for beta-3 receptors with virtually no binding affinity for α-1 and α-2 as well as β-1 and β-2 adrenoreceptors. This is important as stimulation of beta-1 and beta-2 adrenoceptors typically leads to increases in heart rate and/or blood pressure.
Both alone and in combination with caffeine, P-synephrine has been shown to exert a thermogenic effect in the body by increasing resting metabolic rate, lipolysis and exercise performance as well as reducing food intake.[9,10]
Forskolin is one of the most intriguing thermogenic supplements. Yet it is not a stimulant, like so many other common fat-loss ingredients.
Forskolin hails from the Indian plant coleus forskohlii. It’s the active component buried within the plant that’s been documented to activate an enzyme in brown fat called adenylyl cyclase. Activation of this enzyme leads to increases in cyclic AMP (cAMP) levels, which typically only occurs when noradrenaline (one of the body’s fat-burning catecholamines) binds to a beta-receptor. When this occurs, thermogenesis is activating.
Since forskolin increases cAMP levels in brown fat without binding to beta-receptors or causing an increase in noradrenaline, this means it also promotes thermogenesis.
In fact, various animal studies have documented that forskolin increases oxygen consumption and thermogenic activity of brown fat.
This means that for those seeking accelerated fat loss, it may behoove them to stack forskolin with a beta-receptor agonist such as p-synephrine. Together, these compounds both agonize beta-receptors and increase cAMP levels, which promotes increased cAMP levels, lipolysis and most importantly, calorie burning.
Research has even shown that forskolin supplementation accelerates fat loss and may also increase testosterone levels.[24,25]
Dopamine is one of the most powerful and important neurotransmitters/hormones in the human body. Not only is it responsible for allowing us to experience reward, motivation and pleasure, it’s also vital to maintaining focus, motor control and the ability to make decisions.[13,14]
There’s one other “trick” you can add to the list of things dopamine does – ignite thermogenesis.
The next question is, “how do we increase dopamine?”
Well, there are several ways you can do that, including caffeine and exercise. But since we’ve already commented on caffeine, let’s instead shift to compounds that directly impact dopamine production, namely the two powerful dopamine precursors, L-Tyrosine and L-Dopa.
Research has shown that supplementation with either of these potent dopaminergic activators increases dopamine production and function, which ignites a cascade of physiological processes in the body that results in increased energy expenditure in a dose-dependant manner.[15,16,17]
In other words, the more dopamine you have circulating in your body, the greater amount of energy expenditure that occurs.
Since supplementation with both L-Tyrosine and L-Dopa has been shown to significantly increase dopamine levels in the body, it stands to reason that supplementation with them supports increased thermogenic effects in the body, leading to better fat loss.
Pungent Spices (Capsaicin, Piperine, Ginger (Gingerols), Cinnamon)
Without spices, many of your favorite foods wouldn’t be much better than the bland bro-tastic meal of baked chicken breast and steamed broccoli.
Spices give culinary fare nuance, depth and bite. They help inject life into that broiled, grilled or pan-fried hunk of animal flesh and tantalize your taste buds to keep you coming back for more.
They can also help ignite your internal fire and rev your metabolism, too
Best of all, you don’t have to scour the Far East to unearth these potent flavor bombs; most of you reading this likely have these spices in your own kitchen right now.
Research has identified four key spices that boost metabolism and enhance fat loss. Those four spices are:
- Capsaicin (present in chile peppers)
- Piperine (present in black better)
- Gingerol (present in ginger)
- Cinnamaldehyde (present in cinnamon)
Capsaicin is the tongue-numbing alkaloid that gives chile peppers their distinctive bite. It binds directly to the TRPV1 receptor in the oral cavity, causing noradrenaline to be released, which as we mentioned above is very good for stimulating brown fat thermogenesis.
Several interesting pieces of research have shown that ingesting just a single dose of capsaicin can ramp up brown fat thermogenesis.[19,20] And, when used continuously for six weeks, capsaicin supplementation leads to reduced body fat.
But that’s not all – the same study also found significant thermogenic activity in brown fat in individuals with very low amounts of brown fat. This indicates that capsaicin, consumed consistently, may lead to an increase in brown fat stores in the body.
Now, there’s a bit of decision-making you have to do when deciding on what form of capsaicin to purchase, as there are several variations floating around the market. By and large, these “alternative” forms of capsaicin use an enteric-coating or time-release technology to delay the release of the capsaicin alkaloids into the body.
The reason for this is that in some people ingesting pure capsaicin can lead to an intense warming sensation in the body and a bit of GI upset.
Coating the capsaicin helps avoid this GI upset, but it comes with a cost.
You see, capsaicin targets the TRPV1 receptors, the majority of which are located in the oral cavity and upper GI tract.[41,42] By using an enteric-coated, delayed-release form of capsaicin, you are bypassing many of the prime targets for capsaicin, which could significantly reduce the compounds metabolism-boosting potential.
In fact, researchers estimate that an individual would need to consume roughly 2-3 times the amount of enteric-coated capsaicin to account for its delayed release.
Now, there’s a close capsaicin relative known as dihydrocapsiate. It’s found in the CH-19 sweet pepper and is touted to be about 1,000 times more potent than capsaicin in terms of lighting up your tastebuds.
It’s also been noted that dihydrocapsiate shares the same beneficial metabolic qualities as capsaicin without inducing the unwanted GI side effects.
Despite sharing some similarities, capsiate has been noted to be less effective than capsaicin, especially during periods of negative energy balance (i.e. dieting).[44,45]
The takeaway on capsaicin is that if you want to take full advantage of the compounds potential use the pure, simple form. And, if you’re worried about minor GI upset, you can take your serving of capsaicin alongside a meal, which reduces feelings of heartburn.
Moving on from the powers of capsaicin, we turn our attention to three other distinct spices in black pepper, ginger and cinnamon. Each of these culinary staples contain a unique chemical which has been shown to induce thermogenesis (and increase energy expenditure) via activation of TRPV1 family of receptors.[21,22,23]
Prevalently found in apple peels and the Ayurvedic herb Holy Basil, ursolic acid is an intriguing thermogenic supplement. Research has noted that the compound may be capable of increasing the amount of brown fat in the body via increasing activity of uncoupling protein (UCP-1).
Additional research indicates that ursolic acid may have anabolic properties too, increasing muscle mass and limiting protein degradation. An animal study from the University of Iowa documented that ursolic acid prevented muscle breakdown following food deprivation (fasting) and spinal cord injury.
Together, these actions make ursolic acid an incredibly intriguing supplement to consider using regardless if your goal is to burn fat, build muscle or recomp.
Ursolic acid owes its pro-muscle building effects to mimicking the effects of the favorite whipping boy of low-carb dieters, insulin. Specifically, ursolic acid beneficially impacts insulin signaling in skeletal muscle (a very good thing for hypertrophy) while also limiting activity of a gene associated with atrophy.
Olive Leaf Extract
The Mediterranean Diet has been lauded for over a decade for its heart-healthy benefits and is perennially highlighted as one of the best diets for overall health and weight loss.
In addition to a heavy emphasis on nutrient rich, whole foods, the Mediterranean diet also promotes the regular consumption of olive oil, a tasty liquid chock-full of monounsaturated fats.
As most of you know, olive oil comes from pressing olives found on the olive tree. The leaves of the olive tree (as well as olive oil itself) are rich in a potent polyphenol called oleuropein.
So, how does this olive oil chemical enhance fat burning?
Above, we mentioned a protein in fat cells called UCP-1 (uncoupling protein-1).
Since their discovery, uncoupling proteins have generated an immense amount of interest from dieters and obesity researchers due to their ability to cause cells to dissipate energy as heat, instead of storing it as fat or using that energy to generate ATP.
It’s also important to note that UCPs account for roughly 10% of the mitochondrial protein content in BAT and plays a significant thermogenic role in it as well.
Animal studies have found that supplementing with oleuropein increases levels of the fat-burning hormones adrenaline and noradrenaline, and it also ramps up uncoupling activity, which would lead to increased energy expenditure.
Additional studies indicate that supplementation with olive leaf extract support thyroid function and may increase thyroid hormone T3 2.5x above baseline. As you’re probably aware, dieting for prolonged periods of time can result in reduced thyroid function and a slower metabolic rate.
Supplementing with oleuropein in the form of olive leaf extract may provide two separate mechanisms for enhancing weight loss and shedding unwanted body fat.
No doubt you’ve heard of many of the compounds on this list, but one you probably haven’t encountered is a little chemical called kaempferol.
Kaempferol is another potent polyphenol noted to have some fairly impressive thermogenic properties. It’s naturally occurring in a variety of dietary staples including broccoli, tea and grapefruit and has been noted to stimulate thermogenesis in muscle cells.
Believe it or not, fat cells aren’t the only ones that burn energy via thermogenesis, muscle cells do too. As you’re aware, skeletal muscle is one of the main factors impacting your basal metabolic rate (BMR) – the more muscle you have, the higher your BMR is.
And, you’re also probably aware that muscle contractions generate heat, which is part of the reason you feel hot and start sweating during intense exercise. Well, researchers have recently discovered that skeletal muscle also performs non-shivering thermogenesis, meaning it can give off heat and burn energy outside of exercise.
Kaempferol has been documented to increase skeletal muscle thermogenesis and it also stimulates thyroid hormone production, which subsequently activates thermogenesis in brown fat.
What this means is that kaempferol has the extremely rare ability to induce thermogenesis in different types of cells in the body.
Melatonin is a hormone naturally produced by the body most often associated with sleep and helping set the body’s internal clock, a.k.a. circadian rhythm.
But, that just begins to scratch the surface of the many roles melatonin serves in the body.
It also plays a role in energy metabolism and bodyweight maintenance. Numerous studies have noted that melatonin supplementation leads to reductions in total bodyweight and abdominal fat.
Here’s the kicker – those reductions in weight and fat mass can without subjects eating less food or increasing their amount of physical activity. This suggests that the boost in energy expenditure is due to brown fat activation.
Now, those findings were from animal studies, so the same results may not directly carry over to humans, but melatonin has a pretty robust track record for improving sleep in humans, so it’s not too much of a stretch to think that it may also support fat loss.
And, as it turns out, there is some human research showing melatonin supplementation promotes weight loss. A study from Aarhus University in Denmark found that women using 5mg of melatonin (the amount typically contained in most sleep aids) per day reduced body fat by almost 7% and increased lean mass by 5.2%.
Bile acids are produced from cholesterol and serve an important role in digestion where they act as emulsifiers for fat to improve digestion.
The use of bile acids as a supplement has been considered as a means to enhance fat loss due to their ability to stimulate thyroid hormone function, which ramps up thermogenesis in brown fat.
More specifically, bile acids can bind to the TGR5 receptor located in the cellular membrane of brown fat. Following this activation of TGR5, expression of the enzyme deiodinase increases.
Deiodinase stimulates the production of the active thyroid hormone T3 (triiodothyronine). As we explained above, increasing thyroid function is very good for raising metabolism, and more specifically thermogenesis. With greater T3 comes an increase in uncoupling protein-1 activity, which boosts BAT activity.
In fact, researchers from Maastricht University Medical Center in the Netherlands observed that ingesting supplemental chenodeoxycholic acid (one of the acids found in bile) increased brown fat activity in adult women.
THE BEST THERMOGENIC, BAT-ACTIVATING SUPPLEMENT
As we stated at the beginning of this article, most thermogenic fat burners you’ll find do very little in the way of actually helping you burn fat.
But, that doesn’t mean all fat burners are junk. In fact, fat burners can be particularly effective for helping you shed those unwanted pounds – if they’re formulated with scientifically backed ingredients.
AML ThermoHeat is that fat burner.
ThermoHeat has been meticulously formulated to help activate brown fat, boost metabolism, increase energy expenditure and most importantly, lose weight. Try AML ThermoHeat for yourself today and see what a real fat burner, built on science, can do for your weight loss goals.
© Published by Advanced Research Media, Inc., 2023
© Reprinted with permission from Advanced Research Media, Inc.
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