When evening chai disturbs dream time

Key points

• “Caffeine comes not just through coffee and chai but also through caffeinated sodas and ‘cold drinks’.
• And when sleep is affected, it can have an interesting effect on what we remember from the night.
• However, the connection between caffeine and REM is not quite as simple as saying that caffeine eliminates dreaming.
• With that distinction in mind, the solution does not necessarily have to be giving up chai altogether.

There is something comforting about an evening cup of chai. As the day winds down, the familiar clink of the cup and the first warm sip can feel like a small pause before bed. Yet, that innocent-looking cup may quietly follow us into the night, affecting not only how quickly we fall asleep, but additionally how much of our dream world stays with us by morning.

For Dr Soumya Parimi, FCCP, ABIM (Pulmonary and critical care medicine), director of the department of pulmonology at AIG Hospitals, Banjara Hills, the evening cup is often one of the first things worth discussing when someone comes looking for help with sleep. “Caffeine comes not just through coffee and chai but also through caffeinated sodas and ‘cold drinks’. While increasing brief awakenings, consumed later in the day, caffeine increases the time it takes to fall asleep, reduces sleep quality and deep sleep. Individual sensitivity can vary widely due to genetic differences,” says Dr Soumya.

The reason that evening cup can linger into the night is that caffeine continues to work in the body even after its stimulating effects become less noticeable. Dr Pragya Rashmi, consultant psychologist at Yashoda Hospitals, explains the process this way: “Caffeine works by blocking adenosine, a brain chemical that builds up during the day and promotes sleepiness. After you drink chai, caffeine is absorbed quickly, and its effects can last numerous hours because the liver breaks it down gradually. Even when you don’t feel ‘alert,’ residual caffeine can reduce sleep depth and delay the time you fall asleep. So you may think you’re fine, but the quality of your sleep — especially the deeper stages — can be subtly affected, leaving you less rested the next day.”

And when sleep is affected, it can have an interesting effect on what we remember from the night. Dream recall is closely connected to REM (Rapid eye movement) sleep and the small awakenings that happen around it. Dr Soumya explains, “Dream recall depends heavily on REM sleep and, importantly, on brief awakenings out of or near REM. People most reliably remember dreams when they wake up during or immediately after a dream. Anything that reduces the quantity, timing, or continuity of REM-rich sleep can reduce how often dreams are remembered. Because caffeine close to bedtime can prolong REM sleep latency and cause less REM overlapping with natural morning awakening, it could lead to fewer remembered dreams.”

However, the connection between caffeine and REM is not quite as simple as saying that caffeine eliminates dreaming. While changes in REM sleep may affect what we remember, they do not necessarily mean that dreams themselves disappear. Dr Soumya points out, “Caffeine’s effect on the overall percentage of REM sleep is small and not statistically significant. So, caffeine does not dramatically reduce the total proportion of REM in most studies. As mentioned above, however, caffeine does appear to alter REM timing and continuity. Clear, direct studies linking caffeine specifically to dream-recall frequency are limited.”

With that distinction in mind, the solution does not necessarily have to be giving up chai altogether. Instead, the timing of that familiar cup may be what matters most. Dr Soumya recommends, “Set a caffeine cutoff by avoiding caffeine intake at least 6-8 hours before bedtime, so if you typically sleep at 10.30 pm, avoid anything caffeinated after 2.30 pm. Replacing the evening chai routine with a non-caffeinated option, such as herbal tea, can help. As higher doses disrupt deep sleep and provoke anxiety, keep intake within a moderate range. Older adults and anxiety-prone individuals should stop caffeine earlier, drink less, and pair this with good sleep hygiene.”

Moving the cup earlier may help protect sleep, but changes in dream recall alone are not necessarily a reason for concern. Dr Pragya concludes, “A shift in dream recall on its own isn’t always problematic. Reduced dream recall could just be the result of a shorter or lighter REM due to caffeine. By contrast, if the shift is accompanied by drowsiness during the day, difficulty focusing, mood swings, or frequent nighttime awakenings, it indicates that sleep quality is compromised and needs to be assessed.”