What Are the Health Benefits of Green Tea?
There can be many benefits to drinking green tea and eating green tea products. Science has discovered that green tea can form natural antioxidants, providing benefits to our systems through its natural antiviral and anti-plaque properties.
It can also reduce our risk for developing certain cancers, high blood pressure, cholesterol, body fat, fat accumulation in the liver and high triglycerite levels, while increasing calorie and fat burning at rest.
What is Catechin?
In a 2005, study in The American Journal of Clinical Nutrition by T. Nagao et al, proved that a keytone-containing flavonoid (known as catechin) which can be found in green tea, promotes weight loss and reduces body fat in humans.
Weight Loss and Green Tea – The Catechin Connection
People can experience a significant reduction in weight and body fat when they drink a green tea product highly-enriched with catechin, compared to those who take the product with low levels of catechin. And this is true, regardless of whether or not the tea is caffeinated or decaffeinated.
In a follow-up study of men with similar body mass index scores who were either at the upper limit of their normal weight or slightly above, T. Nagao and his team of researchers investigated the effects of green tea catechins on body fatreduction and waist circumference.
Nagao gave men in the study a highly enriched catechin, decaffeinated green tea product (at a rate of 690 mg per day) while giving the control group a decaffeinated green tea product that contained catechins at a lower dose of 22 mg a day.
Catechin in Green Tea Makes a Difference
After 12 weeks on the study, the men who received the highly-enriched catechin decaffeinated green tea product showed a significant reduction in body weight, waist circumference and body fat, as compared to the men who took the decaffeinated green tea product with depleted levels of catechin.
I’ve broken down the results of this study so you can better see the difference for yourself:
Average Weight Loss
- The Catechin-Enriched Group – 5.3 lbs
- The Catechin-Depleted Group – 2.9 lbs
Average Waste Circumference
- The Catechin-Enriched Group reduced by – 3.4 cm (or 1.36 inches)
- The Catechin-Depleted Group reduced by – 1.6 cm (or 0.64 inches)
Reduced LDL Cholesterol Levels
- The Catechin-Enriched Group – from 3.38 mmol/L (or 130 mg/dl) to 2.99 mmol/L (or 115 mg/dl). In addition, they realized a rise in their HLD-cholesterol levels
- The Catechin-Depleted Group – LDL cholesterol reduction was much less pronounced.
Lose More Weight When You Exercise with Catechin
In 2008, C.K. Maki and his team undertook a 12-week study involving overweight subjects (both male and female) who were given a highly-enriched catechin supplements at a rate of 625 mg a day.
The results showed an increase in weight loss when exercise was introduced at a rate of 3 hours a week, compared to the remainder of the control group who were not placed on the highly-enriched catechin product. There was also a significant reduction in the levels of abdominal fat and triglycerides in the group who ingested highly-enriched levels of catechin.
Catechin in Green Tea Attacks Brown Fat!
Another study performed by a researcher named Dulloo and his team found that certain green tea catechins can increase thermogenesis (the process by which our bodies raise their own temperatures) in the brown fat tissue of rats.
The study also suggests that consuming GTE (green tea extract) will increase energy in humans, and that one of the reasons catechins are so affective is because they inhibit an enzyme that attacks and degrades catecholamines (the natural neurotransmitters or hormones found in our bodies, dopamine, epinephrine and adrenaline.)
As a result, when natural hormones and neurotransmitters – like epinephrine and norepinephrine (catecholamines) – have a stronger presence in our bodies, they encourage fat cells to release more fat, regulating brown fat activity that also increases the level of fat burned while at rest, possibly leading to an increase in the total number of calories we burn every day.
Catechin May Discourage Fat Accumulation in the Liver
Catechins help our bodies by decreasing lipid oxidation (the process that happens when dangerous free radicals steal important electrons from our cells). Studies suggest that obesity mightbe related to an increase in lipid oxidizability, as it can damage the receptors that help to metabolize of our system’s fat process. As a result, green tea catechins may discourage fat accumulation in fat cells and liver by decreasing fat oxidation in the body.
Are There Benefits in Decaffeinated Green Tea?
Authors of these and other scientific trials have studied how green tea catechins help promote fat burning and weight loss without adverse stimulation to the central nervous system. So the benefits are the same, whether you ingest caffeinated or decaffeinated green tea.
This is great news, as people can reap the benefits of green tea and catechin without needing to be concerned over possible adverse reactions to stimulants; a win/win if there ever was one.
Some Final Thoughts on Green Tea
In addition, studies have also found that the catechin in green tea can stop the formation of oxidized lipids that would normally put us at risk for arteriosclerosis, and ingesting catechin has been proven to decrease body fat in humans and animals without resulting in any adverse side-effects or events.
Studies also suggest that catechins can contribute to the prevention of lifestyle-related diseases, particularly obesity and cardiovascular disease. They may also promote body fat reduction and boost the effectiveness of our body’s own adrenaline on our fat metabolism.
In summary, ingesting green tea products – either caffeinated or decaffeinated – high in catechin green tea can help to reduce body fat and your odds for developing atherosclerosis, high cholesterol and other lifestyle-related diseases.
References:
Nagao T, Komine Y, Soga S, Meguro S, Hase T, Tanaka Y, Tokimitsu I. Ingestion of a tea rich in catechins leads to a reduction in body fat and malondialdehyde-modified LDL in men. Am J Clin Nutr 2005-81; 1:122-129. 2005
Maki KC, Reeves MS, Farmer M, et al. Tea catechins and exercise-induced weight loss. The Journal of Nutrition. doi: 10.3945/jn. 108098293
Dulloo AG, Seydoux J, Girardier L, Chantre P, Vandermander J. Green tea and thermogenesis: interactions between catechin-polyphenols, caffeine and sympathetic activity. Int J Obes Relat Metab Disord 2000;24:252–8.
Dulloo AG, Duret C, Rohrer D, et al. Efficacy of a green tea extract rich in catechin polyphenols and caffeine in increasing 24-h energy expenditure and fat oxidation in humans. Am J Clin Nutr 1999;70:1040–5.
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