ECGC Revs Up Your Metabolism

ECGC Revs Up Your Metabolism and Suppresses Inflammation

The prevalence of obesity has steadily increased over the past three decades both in the United States and worldwide. Recent studies have shown the role of dietary polyphenols in the prevention of obesity and obesity-related chronic diseases. A recent review paper published in the prestigious Journal of Nutritional Biochemistry titled,” Novel insights of dietary polyphenols and obesity.“ suggests that tea may be a way to prevent and treat obesity. The researchers evaluated the impact of commonly consumed polyphenols, including green tea catechins and epigallocatechin gallates, resveratrol, and curcumin, on obesity and obesity-related-inflammation. Cellular studies demonstrated that these dietary polyphenols suppress the formation of new fat cells, stimulate fat mobilization, and also reduces inflammation.

Obesity and Inflammation

One of the major findings of the decade is that fat cells are not just inactive globules but instead adipose tissue is an active endocrine cell. Adipose tissue sends out important hormones that are critical to overall energy balance and homeostasis. One interesting finding that obesity researchers have found is that adipocyte cells from obese patients are inflamed. Thus, obesity is a chronic low-grade inflammation.

Putting out the Obesity Inflammation Flame

The beneficial effects of some diets such as the Mediterranean diets for weight loss are attributed for the most part to the significant amounts of bioactive components with recognized anti-inflammatory and anti-oxidant properties of the fruits and vegetables in the Mediterranean diets. In a systemic review by Esfahani et al, the authors reported that daily consumption of mixed fruits and vegetable supplements significantly increases serum levels of antioxidant pro-vitamins and vitamins (β-carotene, vitamins C and E) and folate and reduces homocysteine and markers of oxidative stress. These findings emphasize the beneficial effects of food components and further support the dietary recommendations for Americans that emphasize diets rich in fruits and vegetables for the prevention of chronic diseases including obesity. Indeed, several cell, animal and human studies provide strong evidence that dietary bio-active compounds act as anti-oxidant and anti-inflammatory agents to increase thermogenesis and energy expenditure while decreasing inflammation and oxidative stress, further supporting progress towards weigh loss and/or decreased metabolic disorders. This inflammation-associated obesity can be prevented or even reversed with weight reduction that can be achieved via energy restriction, increased physical activity, and anti-oxidant rich foods. For example, consumption of foods rich in bio-active anti-inflammatory compounds, such as omega-3 fatty acids and polyphenols, has been documented to decrease inflammation. Another potent ingredient that reduces inflammation is green tea.

Green Tea: Mothers Nature’s Fire Extinguisher for Inflammation

Green tea is made from the dried leaves of the Camellia Sinensis plant. Compared to black tea and oolong tea, green tea contains the highest amount of green tea catechins, the major polyphenols in green tea that constitutes about 35% of its total dry weight. A 2-gram bag of green tea contains about 500 mg of green tea catechins. The most abundant green tea catechins are (−)-epigallocatechin gallate (EGCG), which accounts for about 68–69% of green tea catechins. The anti-obesity potential of green tea catechins, particularly EGCG, has been shown in cell culture, animal and human studies.

Several systemic reviews have been published in the past four years. Based on a meta-analysis of 11 studies, Hursel et al. concluded that catechin or an EGCG-caffeine mixture contained in green tea had a small effect on weight loss and weight maintenance. Phung et al. reported that participants in intervention groups who received green tea catechins (GTC) in combination with caffeine had a decreased BW and waist circumference, compared with the control groups containing similar amounts of caffeine.

Published studies show that obesity-associated inflammation, a major contributor to metabolic disorders in humans, can be prevented or partially reversed by dietary polyphenols such as those reviewed herein. Mechanistically, these dietary polyphenols exert their additive and/or synergistic effects through reducing obesity related inflammation. However, most dietary polyphenols have relatively short half-lives once ingested due to rapid metabolism, so it is important that their consumption is maintained throughout the life span. In summary, cellular and animal studies have shown that dietary supplementation with EGCG or GTE is a potentially viable nutritional strategy for the prevention of obesity.

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