Research
Research suggests camellia sinensis (green tea leaf extract), contains an epigallo catechin gallate (EGCG) caffeine mixture. This EGCG caffeine mixture is an excellent source of antioxidants which help with the maintenance of good health and weight management.3,4 Many human studies have demonstrated the positive effect of green tea on weight management.5,6,7,8,9 Research also indicates that green tea suppresses appetite and decreases energy intake.10 Additionally, green tea catechin supplements and caffeine have been demonstrated to have a positive effect on blood glucose levels.11,12 It has been proposed that green tea is able to exert effects on weight management through a synergistic effect of both EGCG and caffeine on thermogenesis, fat oxidation, and sparing fat free mass during weight maintenance.13 Even though caffeine has been shown to promote weight management the effect of caffeine with EGCG present in green tea, has been shown to have a greater effect than caffeine alone on weight management.14 As a result, the use of caffeine independent of green tea does not have the same effects on 24-hour energy expenditure or fat oxidation.15 Green Tea, when used in the ratio of 15% EGCG to 8.3% caffeine for an average of 12 weeks, demonstrates a positive effect on weight management.16,17,18 Green tea is also thought to confer cardiovascular protection by decreasing LDL cholesterol and triglycerides as well as by blocking platelet aggregation.19,20
L-glutamine is an amino acid produced primarily in skeletal muscle. Although classified as a non-essential amino acid, L-glutamine is essential for maintaining intestinal function, immune response, and amino acid homeostasis during times of stress, and thus is often called a conditionally essential amino acid. L-glutamine is released into circulation when required, particularly in times of metabolic stress. When the body is experiencing physical stress, the body may consume more glutamine than the skeletal muscle can produce. Progressive muscle breakdown (wasting) can occur as the body tries to meet glutamine requirements.21,22,23 As a result, muscle function can decline as progressive muscle breakdown occurs. Supplementation of L-glutamine has been shown to be beneficial to enhance exercise performance.24,25,26,27 In general, L-glutamine helps support digestive system health after periods of physical stress, is linked to energy metabolism and physical activity, and is important in sustaining immune function.20,28,29,30 L-glutamine has also been found to increase carbohydrate oxidation and promote meal related energy expenditure. L-glutamine has been found to increase post-meal energy expenditure by increasing post-meal carbohydrate oxidation and fat oxidation.31 Preliminary evidence proposed L-glutamine supplementation may prevent hyperglycemia and hyperinsulinemia, suggesting it to be a useful in increasing insulin sensitivity.32
Resources
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2 Health Canada. Natural Health Products Directorate. Product Monographs. Glutamine. Available at: www.hc-sc.gc.ca Accessed Jan 31, 2011.
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