Every day, we’re bombarded with advertisements pushing fat burners guaranteeing us a perfect body with little or no effort. Unfortunately, too many people rely on these hollow promises only to be disappointed. If you want to change your body, the answer isn’t in a bottle alone; it’s in a personal commitment to smart, healthy eating habits and regular exercise. Any promise short of that is a lie!
If you are serious about making a change in your body and have started eating healthier and exercising, than adding a fat burner to your supplement stack may make sense and help you reach your goals quicker. Ideally, fat burners should contain key nutrients that can enhance your body’s ability to become lean. These nutrients target multiple aspects of weight loss, including appetite stabilization, improved metabolism, fat blocking, insulin control, blood sugar stabilization, and fat utilization.
This article will discuss five ways fat burners work to promote fat/weight loss through the use of research-proven ingredients.
Five Ways Fat Burners Work to Support Weight Loss
1: Boost Metabolism
Key Ingredients: Caffeine, Green Tea Extract
Previous research has reported that caffeine and caffeine-containing supplements can acutely increase resting metabolic rate. Even small doses of caffeine (100 mg) have been reported to significantly increase resting metabolic rate by approximately 4% over a 2.5-hour period following ingestion. The magnitude of the resting metabolic rate response is linear with increasing dosages of caffeine intake. Specifically, doses of approximately 100 mg, 200 mg, and 400 mg of caffeine have been shown to significantly increase resting metabolic rate up to a 3-hour period by about 4%, 11%, and 16%, respectively.
In addition to its impact on metabolic rate, caffeine can affect substrate utilization during exercise. In particular, research findings suggest that during exercise, caffeine acts to decrease reliance on glycogen use and increase dependence on free fatty acid mobilization. Essig et al. reported a significant increase in intramuscular fat oxidation during leg ergometer cycling when subjects consumed caffeine at an approximate dose of 5 mg/kg. Additionally, Spriet et al. demonstrated that following ingestion of a high dose of caffeine (9 mg/kg), net glycogenolysis was reduced at the beginning of exercise (cycling to exhaustion at 80% VO2max). Consequently, performance was significantly improved. The results of this study suggested an enhanced reliance on both intra- and extramuscular fat oxidation.
In addition to caffeine, green tea extract has also been investigated for its potential to elevate resting metabolic rate. Specifically, these investigations have reported that green tea extract significantly raises 24-hour energy expenditure, possesses thermogenic properties, and promotes fat oxidation beyond that explained by its caffeine content. Also, green tea ingestion resulted in considerably more fat oxidation (12%) compared to a water control.
2: Increase Thermogenesis
Key Ingredients: EGCG, Cayenne Pepper, and Advantra Z®
Thermogenics are compounds designed to amplify body heat production, thereby increasing energy expenditure and promoting weight loss. One such compound is epigallocatechin gallate, also known as EGCG. EGCG has been theorized to increase energy expenditure by stimulating brown adipose tissue thermogenesis. In support of this theory, Dulloo et al. reported that EGCG in combination with caffeine (e.g., 50 mg caffeine and 90 mg epigallocatechin gallate taken three times per day) significantly increased 24-hour energy expenditure and fat utilization in humans to a much greater extent than when an equivalent amount of caffeine was evaluated, suggesting a synergistic effect. Recently, Di Pierro et al. reported that the addition of EGCG to a hypocaloric diet resulted in a significant increase in weight loss (14 kg vs. 5 kg) versus a hypocaloric diet alone over a 90-day clinical trial. Theoretically, the increases in energy expenditure via EGCG supplementation may help individuals lose weight and/or manage body composition.
A second thermogenic compound is cayenne pepper. Studies suggest that chemical compounds in cayenne have the ability to increase the body’s heat production, thus increasing the rate of metabolism of fats and carbohydrates. Additional research also indicates that cayenne increases the production of epinephrine and norepinephrine, which together decrease appetite. For dieters, it has been suggested that adding cayenne to a day’s diet reduces hunger after meals and reduces calories consumed during subsequent meals.
A final thermogenic is the patented compound Advantra Z®. Because Advantra Z® contains synephrine, it can stimulate thermogenesis, increase lipolysis to facilitate the burning of fats for fuel, reduce weight, increase lean muscle mass, and suppress appetite. Advantra Z® also improves athletic performance and uptake of amino acids into muscle cells. Advantra Z® offers many of the metabolic enhancing effects of ephedrine without the dangerous side effects. Unlike ephedrine, Advantra Z® does not influence alpha-1, alpha-2, beta-1, or beta-2 receptors, which affect blood pressure and heart rate, making it a safe and effective tool for weight loss. Advantra Z® only stimulates beta-3 adrenergic receptors, which increase lipolysis in fat tissue and thermogenesis in skeletal muscle.
3: Use Fat as Fuel
Key Ingredient: Carnitine
Carnitine plays an important role in converting stored body fat into energy. Carnitine’s primary function is to regulate fat metabolism and transport fatty acids into the mitochondria of cells, where they are oxidized and converted into energy. Studies suggest that athletes may need more carnitine than their body can produce, so supplementing with carnitine can lead to improved exercise capacity and a reduction in stored body fat.
During intense exercise, carnitine may help reduce the respiratory exchange ratio and lactic acid buildup in muscles, leading to increased energy and greater resistance to muscle fatigue. Put simply; carnitine helps your body burn its stored fat for energy, leading to increased endurance, work output, and exercise capacity. Studies show that it may even preserve muscle glycogen during exercise, keeping you energized even longer.
4: Appetite Suppression
Key Ingredient: L-Tyrosine
Although many of the other active ingredients listed above act as appetite suppressants, L-tyrosine may exhibit the strongest effects when it comes to curbing hunger. This is due to its role in the production of the dopamine, epinephrine, and norepinephrine. These neurotransmitters help create a sense of satiation (feeling of fullness), which in turn contribute to reducing cravings. Furthermore, supplementing with L-tyrosine may be an effective way to safely boost the metabolism of overweight and obese individuals. Tyrosine has been shown to influence the production of thyroid hormone levels, specifically thyroxin, a hormone that regulates the body’s metabolic rate.
5: Reduce Carbohydrate Absorption and Increase Insulin Sensitivity
Key Ingredients: Banaba Leaf, Theobromine
Banaba leaf is an insulin mimetic that has been shown to inhibit the uptake (digestion and absorption) of carbohydrates to a degree and can also aid in their deposition into skeletal muscle cells from the bloodstream, resulting in a reduction in blood sugar. Also, because Banaba contains the compound corosolic acid, it promotes the use of glucose as fuel and promotes weight loss.
Theobromine is a methylxanthine, which is a chemical relative of caffeine. When theobromine is absorbed by the body, it activates an insulin-signaling pathway, which causes a mild increase in glucose uptake. Increased glucose uptake means the body can take in sugar from the blood more effectively.
The Bottom Line on Fat Burners
Maximizing fat loss and achieving an ideal physique first and foremost requires putting in hard work at the gym and in the kitchen. If an individual has not done this yet, it probably makes little sense to use a fat burning supplement. By itself, a fat burner may be able to cause small but significant reductions in weight and adipose tissue but will always be more potent in conjunction with consistent training and healthy eating. For people whose exercise routine and diet are dialed in, a fat burner may help drop a few unwanted pounds or assist with “leaning” out. Finally, when choosing a fat burner, it is vital it contains research validated and clinically dosed ingredients like the ones discussed in this article.
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