Thermogenic fat burners are nutritional supplements that are popularly believed to facilitate the process of weight loss by increasing fat metabolism, impairing fat absorption, increasing fat oxidation while exercising, and sometimes, producing long-term changes which increase fat metabolism. There are many ingredients in these supplements that are purported to have a beneficial effect on weight loss and they are said to have summative effects when taken in combination. Some of these ingredients are caffeine, green tea, conjugated linoleic acid, carnitine, kelp, fucoxanthin, and chromium.
The list of these ingredients is long and is primarily promoted by industry. In fact, according to Chron.com, there is a huge supplements industry that deals in products that claim to have thermogenic fat-burning properties. However, it would be wise to ask oneself these questions before trying them:
- Do these fat burner supplements work?
- What is the scientific evidence that supports these claims?
- Should I discuss them with my doctor before taking them?
In this article, we try to answer these questions as well as look for evidence supporting or refuting the claims regarding the beneficial effect of these thermogenic fat burners on weight loss.
Caffeine is a natural ingredient in many foods. It is also added to a variety of drinks and foods after its extraction from coffee beans or tea leaves. Moreover, there are many caffeine-containing supplements available in the market. Many people consume caffeine in all of these forms.
Caffeine is popularly believed to have a positive role in facilitating the weight loss journey of an individual. These claims are possibly based on studies showing its positive effects on fat breakdown, fat oxidation during light exercise, increasing resting metabolic rate, and hence, promoting weight loss in an individual.
Although these effects have been shown as such in some studies, many studies conclude that these effects are either small or they hold negligible value when a person is doing moderate to severe intensity exercise. To sum up, caffeine has little effect in decreasing the bodyweight of a person.
Carnitine is another supplement that is believed to reduce body weight by increasing fat metabolism. This belief is primarily based on two assumptions. Firstly, oral intake of carnitine supplements increases carnitine concentration in muscles. And the second assumption is that this increase in carnitine concentration in muscles results in increased fat oxidation that leads to loss of body fat. Both of these assumptions have been tested in medical studies and it is found that no such increases occur after ingestion of carnitine.
Fucoxanthin and kelp
Fucoxanthin is found in brown seaweeds. Kelp is a type of brown seaweed. Fucoxanthin promotes weight loss through various mechanisms including increases in resting metabolic rate, decreases in body and liver fat content, and improving the lipid profile of a person. It has been shown in animal research that long-term supplementation of fucoxanthin can help in weight loss.
However, there has been only one human study where its beneficial effects on weight loss have shown to be significant. Although these results show some promise, there is a need for research to provide conclusive answers and understand its mechanisms in reducing body fat.
Green tea is another supplement that has been popularized as a fat burner. It is believed that green tea contains catechin polyphenols and these catechin polyphenols facilitate fat oxidation through various mechanisms. Many studies have explored its effect on fat metabolism at rest and during moderate-intensity exercise. Research has shown that it increases fat metabolism and may help in losing body fat and hence, decreasing body weight.
One study showed that it increases fat oxidation during exercise and another study involving a meta-analysis of 11 studies showed that the experimental group lost 1.31 kg more over 3 months than the comparison group. Although there seems to be some evidence of its potential benefits in reducing body weight, the effects are rather small. More studies are needed to study these effects and study the underlying mechanisms of these effects thoroughly. So for now, scientists conclude that there is not enough evidence to suggest that it reduces a significant amount of body weight.
Conjugated linoleic acid
Conjugated linoleic acid is found in beef and lamb meat and also, in dairy products like cheese and milk. Many commercial preparations also contain different isomers. It is believed to enhance fat oxidation and fat breakdown and also impair the process of fat building and decrease the energy expenditure in the body. It is marketed as an anti-obesity agent.
The majority of evidence of the potential benefits of conjugated linoleic acid is based on studies done on animals. In human studies, there is a lack of consistency in results. It is concluded that they do provide some benefit in reducing body weight but there needs to be more research on these issues to determine their positive effects in weight loss and issues regarding their safety and dosages.
Chromium has been popularized as another fat burner through various marketing campaigns. Chromium is found in American cheeses, mushrooms, and brewer’s yeast. And it is an essential nutrient. Chromium nicotinic acid is the main form in which it has been marketed. A popular belief is that it increases lean body mass in people who exercise. Some studies did show its benefits in increasing lean body mass but these results have not been replicated in the results of various subsequent studies. Also, its changes in lean body mass were found to be very small. To conclude, there is not any conclusive scientific evidence to support the claim that it increases lean body mass. Furthermore, many significant side effects due to its accumulation in the cells have been reported in laboratory studies. Although these results have not been studied in humans, it is advised to take caution in the use of supplements containing chromium.
Many other ingredients like Garcinia Cambogia, Yohimbine, and bitter orange are also popular ingredients in supplements that are believed to facilitate the weight loss journey. But there is also a lack of evidence in research to support these claims. Also, there has not been thorough research in investigating their potential benefits. To sum up, there needs to be conclusive evidence in research to support the claims of their potential benefit in weight loss.
Overall, there is some evidence to suggest that caffeine and green tea do help burn fat but their effect is small as studied in scientific literature. There is no conclusive evidence for the other ingredients, mentioned above, to suggest their recommendation for supplementation to facilitate the weight loss journey.
To lose body weight, CDC recommends following a diet plan and doing regular exercise and it is recommended to consult one’s doctor before including them in your diet.
It is recommended to seek a medical professional’s help before starting any supplements in the weight loss journey. Also, it is advised to develop a healthy lifestyle and follow a diet plan to regulate body weight in the long run.
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