A decaffeinated green tea extract supplement resulted in 32% lower fat burning during exercise and lower adrenaline responses during exercise. No differences in exercise performance were found between the green tea and placebo group. The caffeine content is likely the main constituent enhancing fat metabolism in green tea extract.
SUMMARY OF EGCG GREEN TEA FAT BURNER RESEARCH STUDY
EGCG green tea extract was compared to a a decaffeinated ECGC green tea extract supplement. The decaffeinated ECGC green tea extract results in 32% lower fat burning during exercise and lower adrenaline responses during exercise.
No differences in exercise performance were found between the green tea and placebo group.
The caffeine content is likely the main constituent enhancing fat metabolism in ecgc green tea extract.
Originating from the Camellia sinensis plant, green tea is renowned for its powerful antioxidant properties that actively fight free radicals and reduce oxidative stress, thus bestowing a plethora of health benefits, such as safeguarding nerve cells and potentially extending life
Historically, advocates have praised green tea extract for its ability to enhance fat burning (i.e., thermogenesis) and improve performance. Catechins, identified as the principal active ingredients in green tea, exhibit significant physiological effects. Typically, a 250 mL cup of green tea furnishes 50–100 mg of catechins and 30–40 mg of caffeine.
Various supplemental forms of green tea are available, such as liquids and powders. Green tea is rich in four main catechins: epigallocatechin-3-gallate (EGCG), epicatechin-3-gallate, epigallocatechin, and epicatechin, with EGCG being the most abundant and bioactive catechin, as noted by Kao et al. (2000).
ECGC GREEN TEA EXTRACT WEIGHT LOSS STUDIES
The active ingredient EGCG green tea extract has been controversial for weight loss, with some studies finding enhanced weight loss and others finding no benefit. (Chen et al., 2016; Mielgo-Ayuso et al., 2014) Some discrepancies can be due to differences in dosages and whether the green tea had other ingredients, such as caffeine.
Similarly to weight loss results, some studies have found increases in fat metabolism, whereas others found no benefit. (Bérubé-Parent et al., 2005; Gregersen et al., 2009) Most people will take green tea extract with exercise to lose body fat. Research showed that incorporating a decaffeinated green tea extract supplement (366 mg of EGCG) with moderate physical activity led to a 17% rise in fat burning but no effect on energy expenditure. (Venables et al., 2008)
Some propose that EGCG can boost fat metabolism by enhancing the activity of adrenaline and noradrenaline, potentially leading to more efficient energy utilization and fat loss. (Chen et al., 2005)
Despite the acute increases in fat metabolism, many long-term studies have found that EGCG does not increase fat burning. (Eichenberger et al., 2010; Jacobs et al., 2014) This brings into question whether green tea is a true fat burner.
Does Decaffeinated EGCG Green Tea Extract Increase Fat Burning?
In a noteworthy study, researchers from Swansea University in the UK embarked on an exploration to examine the effects of decaffeinated green tea extract on fat metabolism and the adrenaline response to a maximal exercise bout. The underlying hypothesis was that if EGCG truly has fat-burning properties, then there should be a noticeable increase in peak fat oxidation or fat burning corresponding with an increase in adrenaline hormones, specifically adrenaline and noradrenaline.
In this study, we recruited eight healthy male participants. We then allocated them to receive either an EGCG supplement or a placebo, conducting a single-blind, placebo-controlled trial to maintain the integrity of the study results. It’s important to highlight that the green tea extract administered was in a mega dose. Typically, the standard dosages of green tea extract are between 400-1000 mg, but in this study, participants received a substantial 1450 mg dose of EGCG, which contained less than .1% caffeine, and they also underwent another round with a placebo.
To evaluate the effects, participants underwent a maximum bicycling test until they reached total exercise exhaustion. To ensure consistency, we closely examined the participants’ dietary intake by scrutinizing their food diaries, making certain they maintained a balanced diet consisting of 40.20% carbohydrates, 37.61% fat, and 22.20% protein.
There was no difference in performance for the standardized green tea extract and the placebo groups for performance time, power, heart rate, or oxygen consumption.
The shocking finding was that peak fat oxidation or fat burning was 32% lower for the EGCG supplement. Additionally, carbohydrate use was 49% higher with the ECGC supplement, likely due to blunted fat metabolism. Unlike what is often claimed, adrenaline and noradrenaline levels were lower with the supplement compared to the placebo group. (Churm et al., 2023) Thus, ECGC green tea extract fat burner need caffeine to enhance fat mobilization.