THE SCIENCE BACKED BENEFITS OF GREEN TEA

The current body of scientific evidence highlights several benefits with regular consumption of either green tea or green tea extracts. These range from enhanced weight loss, to increased fat metabolism during exercise, and positive effects on various aspects of health and cognitive performance.

WHAT IS GREEN TEA?

Worldwide there are four main types of tea (white, green, Oolong and black) produced all from the same plant. The tea leaves are processed differently (e.g. green tea is produced from mature tea leaves with minimal processing), this affects their nutritional content. As its health benefits are continuing to be recognised, the consumption of green tea has grown substantially over the last decade. 

DOES GREEN TEA HAVE CAFFEINE IN?

An 8 ounce cup of green tea contains between 35-50 mg of caffeine, which is approximately half of the caffeine content of a cup of coffee. Although caffeine has been shown to exert beneficial effects on exercise and cognitive performance, the caffeine content of green tea should be considered by people who look to minimise their caffeine content.

WHAT ARE THE HEALTH BENEFITS OF GREEN TEA?

Green tea contains a range of bioactive ingredients that may benefit cardiovascular and metabolic health, enhance fat oxidation and positively affect body weight, as well as being beneficial to oral health¹.

DOES GREEN TEA HAVE ANTIOXIDANTS IN?

Green tea is a rich source of catechins, a type of dietary polyphenols which display strong antioxidant, anti-inflammatory and antimicrobial (substance that kills microorganisms) properties ¹.

A study demonstrated that three months daily supplementation with 379mg of green tea extract reduced both systolic and diastolic blood pressures, decreased glucose and insulin levels, lowered inflammation markers and increased markers of antioxidant status in obese⁴.

WHAT ARE THE CARDIOVASCULAR BENEFITS OF GREEN TEA?

Green tea or green tea extract has beneficial effects on cardiovascular health. For example, an observational study conducted in Japan on nearly 40,000 individuals showed a 14% decrease in cardiovascular disease mortality between those who consumed <1 cup of green tea per day and those who consumed ≥5 cups ².

Daily supplementation with a green tea extract (providing ~585mg catechins) over 12 weeks was shown to reduce visceral and subcutaneous fat area, as well as to decrease systolic blood pressure and low-density lipoprotein³, all important contributors to cardiovascular diseases.

DOES GREEN TEA HELP WITH FAT LOSS?

Apart from the caffeine content which can promote fat oxidation, the catechins present in green tea are also suggested to increase fat oxidation⁵. Both acute and chronic supplementation with green tea extract in a quantity of over 500mg/day were shown to increase fat oxidation rates during steady state exercise ^6,7.

Body fat is reduced after green tea consumption, as shown in a randomised controlled study where body fat reduced by 1.6% following chronic supplementation with green tea extract in combination with endurance training for four weeks in recreationally active individuals ⁸.

The beneficial effects of green tea extract supplementation on fat oxidation (during rest and while exercising) and reductions in body weight and waist circumference are supported by several meta-analyses ^9,10. These studies support the use of green tea extract for enhancing fat oxidation and supporting weight loss, particularly when combined with an active lifestyle and a healthy diet.

The fat loss effects of green tea must be considered in conjunction with a healthy, calorie controlled diet. Achieving a caloric deficit (consuming less calories from your diet compared to the number of calories expended by your body) over a prolonged period of time is required for fat loss to occur.   

WHAT ARE THE COGNITIVE BENEFITS OF GREEN TEA?

A beneficial effect of green tea has been shown on various aspects of cognition, including improved memory and attention, as well as brain function assessed via MRI ¹¹. These beneficial effects are likely to be exerted by several nutrients present in green tea. The consumption of caffeine alongside l-theanine, both compounds found in green tea, was previously shown to enhance various aspects of cognition ¹¹, therefore playing a key role in the effects exerted by green tea.

DOES DECAFFINATED GREEN TEA HAVE BENEFITS?

The catechins present in green tea are also contributing to these benefits seen on cognition and brain function through their antioxidant and neuroprotective properties. Both acute and chronic supplementation with decaffeinated green tea catechins was shown to improve working memory, highlighting that the beneficial effects of green tea on cognition take place even in the absence of caffeine ¹².

GREEN TEA IN PHD PRODUCTS

Green Tea Extract is present in Diet Whey to help support your fat loss and lean muscle goals, along with other health benefits.

Supergreen also contains Green Tea Extract to help reach your daily recommended intake of phytonutrients and antioxidants, supporting the body’s immune system and energy levels whilst meeting the nutrition requirements for a healthy diet.

REFERENCES

1. Casey, A., Mann, R., Banister, K., Fox, J., Morris, P.G., Macdonald, I.A. and Greenhaff, P.L., 2000. Effect of carbohydrate ingestion on glycogen resynthesis in human liver and skeletal muscle, measured by 13C MRS. American Journal of Physiology-Endocrinology and Metabolism, 278(1), pp.E65-E75.

2. Burke, L.M., van Loon, L.J. and Hawley, J.A., 2017. Postexercise muscle glycogen resynthesis in humans. Journal of Applied Physiology, 122(5), pp.1055-1067.

3. Koopman, R., Saris, W.H., Wagenmakers, A.J. and Van Loon, L.J., 2007. Nutritional interventions to promote post-exercise muscle protein synthesis. Sports Medicine, 37, pp.895-906.

4. Beelen, M., Burke, L.M., Gibala, M.J. and Van Loon, L.J., 2010. Nutritional strategies to promote postexercise recovery. International Journal of Sport Nutrition and Exercise Metabolism, 20(6), pp.515-532.

5. Churchward-Venne, T.A., Pinckaers, P.J., Smeets, J.S., Betz, M.W., Senden, J.M., Goessens, J.P., Gijsen, A.P., Rollo, I., Verdijk, L.B. and van Loon, L.J., 2020. Dose-response effects of dietary protein on muscle protein synthesis during recovery from endurance exercise in young men: a double-blind randomized trial. The American Journal of Clinical Nutrition, 112(2), pp.303-317.

6. Burke, L.M., Hawley, J.A., Wong, S.H. and Jeukendrup, A.E., 2013. Carbohydrates for training and competition. Food, Nutrition and Sports Performance III, pp.17-27.

7. Zaromskyte, G., Prokopidis, K., Ioannidis, T., Tipton, K.D. and Witard, O.C., 2021. Evaluating the leucine trigger hypothesis to explain the post-prandial regulation of muscle protein synthesis in young and older adults: a systematic review. Frontiers in Nutrition, 8:685165.