Why does tea keep you awake?

Caffeine: The primary reason why tea keeps you awake is due to its caffeine content. Caffeine is a central nervous system stimulant that boosts alertness, suppresses sleepiness, and enhances cognitive function. It exerts its effects by blocking the effects of adenosine, a neurotransmitter associated with sleep regulation.

Type and Amount of Tea: Different types of tea contain varying levels of caffeine. Black tea generally has a higher caffeine content compared to green or white tea. Rooibos tea, also known as red bush tea, is naturally caffeine-free. The amount of tea consumed also affects wakefulness. A strong brew or multiple cups of tea will have a more pronounced effect in keeping you awake.

Individual Sensitivity: Individuals' sensitivity to caffeine can vary greatly. Some people may be more sensitive to the effects of even small amounts of caffeine, leading to sleep disturbances. This sensitivity may be influenced by genetic factors, caffeine intake habits, and overall health conditions.

Combining with Sugar and Milk: Some studies have suggested that adding sugar or milk to tea might diminish the wakefulness effect of caffeine. However, this effect may vary from person to person and depends on individual preferences.

Timing of Consumption: Consuming tea close to bedtime can disrupt the body's natural circadian rhythm and make it harder to fall asleep. Caffeine has a half-life of about 4-6 hours in the body, meaning it takes around this time for half of the caffeine to be eliminated. Therefore, it's advisable to avoid caffeinated tea several hours before intending to sleep.

While tea can be an excellent beverage for its health benefits, including its ability to provide a temporary boost in alertness, it's important to be mindful of caffeine intake and timing of consumption to avoid sleep disruption.