Caffeine accounts for tea’s energizing and uplifting qualities, and can be beneficial to your health. Recent studies indicate that caffeine in small doses have positive effects on your health, and isn’t necessarily bad for you.
CAFFEINE CONTENT OF TEA & COFFEE (approximate milligrams per cup)
- black tea 25-110mg
- semi-green/oolong tea 12-55mg
- white tea 8-16mg
- green tea* 8-16mg
- drip coffee 60-90mg
The given range of caffeine content depends on the variety of tea and how long it is steeped. Shorter steeping time equals less caffeine. If you like strong flavour, but want to avoid caffeine, use more tea leaves and steep for a shorter time. Caffeine starts to release after about a minute.
*Matcha is an exception because it can be prepared in two ways, and can contain as much caffeine as black tea, depending on how much powder is used.
A study about the health benefits of green tea found that the caffeine is an active ingredient in helping your system assimilate antioxidants. Caffeine stimulates the central nervous system, promotes circulation and assists the release of waste products.
Caffeine in tea versus caffeine in coffee
- Coffee gives you a very fast lift, but an equally sharp decline in your energy is felt later.
- Tea gives you a slower, more delayed lift, which leads to a plateau, and then a secondary lift.
- Tea does not give you a sharp decline in energy rather it very gradually decreases so the negative effects of the decrease are felt less than with coffee.
- Drinking black and semi-green teas is an effective way to reduce coffee consumption; start by continuing to drink a cup of coffee in the morning and follow it up with a black or semi-green tea in the afternoon.
Researchers have discovered that white tea contains marginally higher levels of caffeine than green tea brewed under the same conditions. This could occur because white tea oxidizes slightly during withering; whereas, the oxidation process is stopped early in the manufacture of green tea by the steaming or pan firing of the leaves.
Since the term “antioxidant” is similar to “oxidation”, it’s important to clarify the meaning of both. Both have a relationship to oxygen. Oxidation describes the process of combining a substance with oxygen. Black, oolong and white teas are “oxidized” because they are exposed to air immediately after picking, prior to being dried. An “antioxidant” is a substance such as vitamin e, c or beta carotene which inhibits oxidation. They are believed to have health benefits because they protect the body’s cells from the damaging effects of oxidation.
Tea naturally contains antioxidants. The oxidization process does not affect the level of antioxidants in tea. “Oxidation” describes how black, oolong and white teas are processed. Exposure to air causes changes to occur in tea leaves, making it look and taste different, while increasing the caffeine content.
CAFFEINE & NUTRITIONAL CONTENT OF CONVENTIONAL TEABAGS
- Most teabags release up to twice as much caffeine as loose teas because they are made with low grade leaves that are powdered and crushed.
- When a tea leaf is crushed, the surface area of the leaf is exposed to more air, which causes the tea to lose nutrient value, become stale and lose flavour rapidly.
- To counteract loss of flavour, more crushed leaves are used, which results in more caffeine.
- Teabags are generally made with low-grade leaves (the twigs, leaves, stems that are located lower on the tea bush) as opposed to the “top” leaves and bud that are used for high quality loose teas. Lower grade leaves contain less nutrient value, not solely because they are crushed, but also because they are poorer quality to start.
- Many estates produce their entire low-grade tea yield solely for teabag production, and some teabag manufacturers also use leftovers from high-grade tea production (crushed and broken leaves).
- Matcha is the only tea that does not lose flavour or health benefits when the leaves are crushed. Matcha is powdered under very stringent controls, which are designed to keep it fresh and nutrient rich. Its exposure time to air is deliberately very minimal. The same attention is not given to crushed leaves used for most bagged teas.