Tea is suggested to help promote alertness and concentration, but also help promote relaxation. These two benefits seemed inconsistent, they are all true. Different people react differently to the caffeine, so when talking about how tea effect on sleep, there isn’t a simple answer.
How the caffeine affect our sleep?
When we begin to brew a cup of tea, about 70%-80% caffeine solubilized into the water, and the tea liquid with caffeine promotes alertness and makes out brain excited.
Our tiredness comes from a neuromodulator called adenosine, which is produced by our body after one day’s working. When adenosines binding to adenosine receptors, we begin to feel exhaustion, and want to sleep.
However, the caffeine molecules and adenosine look similar, the caffeine can mislead the adenosine receptors and bind with receptors. Blocking the adenosine’s actions keep our brain alert and awake.
Of course, the adenosine receptors will figure out this “mistake”, but we stay awake at least for a while before they recognized each other.
The caffeine in the tea
Normally, the reaction time of caffeine in central nervous system is relatively shorter than that of other stimulants like alcohol. The caffeine will be resolved into other metabolites in an hour. Commonly used beverage like cola, energy drinks and chocolate also contains caffeine, but if we don’t indulge ourselves, they won’t affect our sleep. And if we just have a certain amount of caffeine, all the caffeine will be resolved in 3 – 4 hours. However, the different people react differently to caffeine, so an amount that is safe or pleasant for one person may not be healthy for everyone.
Normally, 200-300 mg of caffeine daily is safe for most healthy adults. However, if you are anxious, easy to lose sleep, highly sensitive to caffeine or are taking certain medications, you’d better not drink too much tea nor to drink tea within 4 hours before your bedtime. And if the caffeine won’t affect you in any way, you can drink tea anytime you want. Don’t indulge yourself with anything, including teas.
Small tips for drinking tea in the evening:
1. Use less tea leaves, less time and lower temperature
Hot water and longer time help release caffeine, therefore when brew a tea in the evening, we can use less tea leaves, brew less time in a lower temperature. However, tea is different from each other, we can’t simply tell how much tea you use, how long you brew it for, water temperature etc. we just recommend the best taste we enjoy. You can try and find the one best for you.
2. Have some herbal tea
All true teas are from the same plant, Camellia sinensis, it naturally bring caffeine. If you are very sensitive to caffeine, and still want to have some drinks in the evening, you can try herbal tea.
herbal tea, also called tisane, is an infusion of non-tea tree leaves, seeds, berries, fruits, and roots, they’re caffeine free. So you can drink some caffeine-free herbal teas in the evening, like chamomile or Camellia etc.
All these are suggestions, you have to pay attention to your own body, and find a best way for you to enjoy the tea as well as health.