Cardiovascular diseases, which lump heart disease, stroke, and other diseases of the heart and blood vessels caused by atherosclerosis and hypertension (high blood pressure) into one category, are the most prevalent causes of death in the world. Studies show that green tea can improve some of the main risk factors for these diseases, which includes helping regulate total cholesterol, LDL cholesterol, and triglycerides. One method by which green tea might help: it significantly increases the antioxidant levels of your blood, protecting LDL cholesterol particles from oxidation—one of the causes of heart disease.
Green tea is processed using either artisanal or modern methods. Sun-drying, basket or charcoal firing, or pan-firing are common artisanal methods. Oven-drying, tumbling, or steaming are common modern methods.[32] Processed green teas, known as aracha, are stored under low humidity refrigeration in 30- or 60-kg paper bags at 0–5 °C (32–41 °F). This aracha has yet to be refined at this stage, with a final firing taking place before blending, selection and packaging take place. The leaves in this state will be re-fired throughout the year as they are needed, giving the green teas a longer shelf-life and better flavor. The first flush tea of May will readily store in this fashion until the next year's harvest. After this re-drying process, each crude tea will be sifted and graded according to size. Finally, each lot will be blended according to the blending order by the tasters and packed for sale.[33] 

Because matcha preparation uses ground tea leaves that cannot be removed after steeping, the caffeine content in a cup of matcha is much higher than that of a cup of tea prepared using tea bags or leaves. However, the exact caffeine content may vary depending on the ratio of water to matcha powder used. Matcha contains less than half the amount of caffeine per cup than in a similar-sized cup of coffee.
In 2009, King’s College researchers found that epicatechin may protect brain cells through mechanisms unrelated to its antioxidant ability, as epicatechin is one of the few flavonoids that can cross the blood-brain barrier. The King’s College researchers reported that somehow epicatechin protects brain cells from the negative effects of beta-amyloid plaques, although the exact mechanism of how this works is still not entirely know. (9)
Matcha (抹茶, Japanese pronunciation pronounced [mat.tɕa], English /ˈmætʃə/[1][i]) is finely ground powder of specially grown and processed green tea leaves. It is special in two aspects of farming and processing: the green tea plants for matcha are shade-grown for about three weeks before harvest and the stems and veins are removed in processing. During shaded growth, the plant Camellia sinensis produces more theanine and caffeine. The powdered form of matcha is consumed differently from tea leaves or tea bags, and is dissolved in a liquid, typically water or milk.
Rooibos tea is anti-inflammatory in nature, which means that it reduces blood pressure and scavenges free radicals like other antioxidants. Quercetin, another powerful antioxidant found in rooibos tea, has been linked to preventing a wide variety of heart conditions. It promotes an increase in HDL cholesterol (good cholesterol) and inhibits the LDL cholesterol (bad cholesterol) from binding to the walls of arteries and blood vessels.