Approximately 80% of the world’s population consume caffeine on a regular basis, but what do we actually know about it?
We put the caffeine guidance on each of our tea listings, but why? Simple: it’s because it’s one of the things we get asked about most often. So we thought we would put answers to the most frequently asked questions in one place.
Before we start let’s establish what the guidelines for caffeine consumption are for a healthy adult. Both the US Department of Agriculture (USDA) and the European Food Safety Authority (EFSA) consider a daily intake of 400 mg of caffeine as safe. This amounts to 2–4 cups of coffee per day. It is further recommended to limit the amount of caffeine you consume at one time to 200 mg per dose. According to the American College of Obstetricians and Gynecologists, pregnant women should limit their daily intake to 200 mg.
The Science bit: What is caffeine and what does it do?
Caffeine is a natural stimulant that is produced by plants to act as a deterrent to pests and bugs. In humans, it has a stimulating effect on the brain and central nervous system. Caffeine is water-soluble and is extracted into the brewed cup when preparing tea. When consumed it is quickly absorbed from the gut into the bloodstream. Caffeine’s main effect is on the brain where it stops you feeling tired by blocking the effects of adenosine, a neurotransmitter that relaxes the brain. Adenosine levels build up over the day, making you increasingly tired and encouraging you to want to go to sleep. Caffeine connects to adenosine receptors in the brain without activating them leading to reduced tiredness. Much of the research that has been conducted on caffeine and humans refer to coffee as it has higher consumable rates of caffeine per oz.
Does tea have more or less caffeine than coffee?
This is a frustrating question because there is no simple answer! When measuring coffee and tea in their dry forms then yes tea has more caffeine than coffee….but keep reading….when comparing brewed coffee and tea, coffee generally has more caffeine than tea! What?! How does that work? Well, I am glad you asked! Normally we use 2-5 grams of tea per 8 ounce cup, and 10 grams of coffee for the same quantity of water. A 2004 British study looked at 200 cups prepared by consumers going about their normal brewing routines. It found that the average caffeine level in the cups of tea (black English teabag style teas) was 40 mg vs 105mg in the average cup of drip coffee.
While the caffeine in tea and coffee are the same the experience is different. Tea contains an amino acid called L-theanine, which reduces stress and promotes relaxation. In tea, it works in harmony with caffeine to calm the body without reducing caffeine alertness. Tea also contains high levels of antioxidants which slow the absorption of caffeine. Together this produces a gentler increase of the caffeine in the system, a longer period of alertness with no crash at the end.