WARNING! CAFFEINE is HIGHLY TOXIC in higher quantities. DO NOT consume more than 600 milligrams (mg) of caffeine daily. Caffeine consumption can cause insomnia and difficulty sleeping. Do not take if you have a history of heart disease or if you are pregnant or nursing. Consult your physician before taking this product.
What is Green Tea with Caffeine?
Green tea extract comes from the oxidized leaves and buds of Camellia sinensis trees. The trees are native to Southwest China, North India, and Northeast India. However, it most likely originated between north Burma and Southwest China. The botanical genus Camellia is the Latinized name of botanist Georg Kamel in recognition of his contributions to the field. The species sinensis is a reference to its place of origin, meaning from China. All types of tea come from Camellia sinensis plants. However, the oxidation process determines the type of tea, with green tea as the least oxidized and black tea as the most.
Because green tea undergoes less processing, it usually has the highest levels of catechins. Catechins are polyphonic flavonoids with antioxidant properties and are likely responsible for the many benefits associated with drinking green tea. Green tea extract contains four types of catechins: epigallocatechin gallate (EGCG), epigallocatechin (EGC), epicatechin gallate (ECG), and epicatechin (EC). While all the catechins have similar properties, EGCG has the most potent effects.
Green tea extracts can contain up to 17.4% of caffeine by total weight. PureBulk manufactures this green tea extract to contain 50% caffeine. However, this caffeine is a natural extract from green tea and is not the anhydrous form. Combining green tea with caffeine can provide unique benefits, as these supplements are synergistic.
Potential Green Tea Extract Benefits
Green Tea Antioxidants
Green tea is richer in catechins than other types of tea. These compounds act as antioxidants in the body by scavenging free radicals and protecting cells against oxidative damage. When free radical levels outweigh antioxidants, they begin to injure cells, promote inflammation, and cause premature aging. Green tea may counteract this inflammation by disrupting pro-inflammatory cytokine activity.
Green tea improves the function of other naturally occurring antioxidants, particularly glutathione. Clinical studies also note that green tea polyphenolic catechins outperform the protective properties of other notable antioxidants like vitamin C and vitamin E. Green tea antioxidants also provide neuroprotection against oxidative stress and heavy metals.
Green tea antioxidants may support heart health by enhancing nitric oxide bioavailability. It helps improve blood flow by promoting vasodilation and expanding arteries. Green tea catechins also block LDL cholesterol oxidation by enveloping LDL particles and isolating free radicals. Oxidized LDL can accumulate on artery walls, cause chronic artery inflammation, and promote lesion development. Additionally, green tea catechins inhibit the enzymes that produce cholesterol from squalene.
Green Tea Extract + Weight Loss
Green tea synergizes with caffeine to enhance weight loss efforts. Combining green tea and caffeine increases the caloric burn required for thermogenesis to digest food and produce body heat. Boosting how many calories the body burns during natural processes may promote faster weight loss. A clinical study found that participants burned 179 additional calories over 24 hours after taking green tea with caffeine. Another study found that combining green tea with caffeine had better thermogenic effects than caffeine alone. Green tea also synergizes with caffeine to augment adrenaline and enhance metabolic rate.
Green tea is a potent fat burner, too. Several studies confirmed that participants taking green tea catechins experienced more overall fat loss than the placebo group. Clinical research also found that combining green tea extract with exercise resulted in superior weight loss than exercise alone. Participants that did not consume caffeine regularly experienced the most weight loss. Green tea also influences metabolism by inhibiting carbohydrate digestion and forcing the body to burn fat for energy.
Green Tea Extract + Exercise Performance
Athletes may benefit from taking green tea supplements. Green tea antioxidants help delay muscle fatigue by inhibiting oxidative damage. Strength training enhances green tea antioxidant protection, which may further fuel its ability to reduce muscle fatigue. A study on sprinters found that green tea supplements protected the athletes against oxidative damage. Additional research found that taking green tea supplements for four weeks increased the participants running distance by 10.9% compared to those taking a placebo.
Green Tea Extract + Skin Health
Green tea may support healthy and youthful-looking skin. It prevents skin aging by scavenging free radicals and protecting against the damaging effects of UV rays. It’s also proven to be helpful with aging skin, skin redness, and acne. Topical green tea extract also enhances skin moisture and elasticity.
Potential Green Tea with Caffeine Side Effects
Green tea is a popular beverage that many people drink without issue. Most individuals can take green tea extract without adverse effects. Numerous human studies also confirm the overall safety of green tea catechins. Excessive doses of green tea extract over long periods may damage the liver or kidneys. Caffeine may cause side effects, which are more pronounced in caffeine-naïve individuals. These include jitteriness, upset stomach, withdrawal headaches, and bowel urgency. Taking caffeine in the afternoon may delay or interfere with sleep. Do not exceed the recommended dosage, as caffeine toxicity can occur with as little as a couple of grams.