It’s ironic that enthusiasts for tea as a wonderful aid to good physical health so often at the same time ring the alarm bells about its dangers after 6 pm. The calming, soothing enhancer of psychological well-being turns into “No caffeine just before bedtime” as almost a diktat. Tea will keep you awake, disrupt your sleep patterns, and create a “sleep deficit” that will push you to consuming more tea (or the demon coffee) next day.
Sleep used to be a simple process of snuggle down in your bed at the end of day. It is now a real challenge for many people: disruptive work schedules, time zone shifts, early morning gearing for the highway commute battles, and late nights – you know them well. Caffeine has become embedded in our routines in dealing with many of these.
But what about bedtime? What drink can you personally choose that will help you get to sleep, stay asleep and wake up feeling fresh? Must you avoid caffeine entirely, hold it to a low amount or pick only certain types of tea? You have three main choices, each of which comes with general positives and negatives but also affects individuals in entirely different ways:
Coffee: Very high caffeine; energizing, not relaxing. Many coffee drinking cultures such as France, Scandinavia and Mexico, aren’t concerned with caffeine as a problem, but there is no question that it does have a direct and largely disruptive effect on sleep for many individuals.
Tea: Often assumed to be in the problem category in terms of caffeine, misleadingly so. Offers a wide variety of choices that many tea drinkers are scared away from taking up only because of clichés about caffeine and arrant nonsense about green and white teas versus black and oolong ones. May be an option to forego for the caffeine-intolerant, but not an inevitable cause of sleep disruption for most.
Herbal drinks: Not the preferred and healthy choice that they are too often touted as. Many side effects, some quite dangerous.
Sodas, alcohol and just plain water are also options, of course, but these three are the ones most likely to be part of your being able to nod off rather than grimace in response to “Sleep well.”
But what about all that caffeine?
The central issue in picking among them is caffeine, of course. The commonsense view is that caffeine is a stimulant that you should avoid entirely around bedtime. So, no coffee but maybe green tea (low caffeine) and white tea (lower). Those two commonsense sentences are anything but that. The commonsense is more old wives’ tales than grounded fact. Caffeine is not a yes/no issue. Green and white teas offer no real advantages over black tea and are often incorrectly classified in caffeine content. They have become marketing glosses added to the folk wisdom of tea.
Most people will have no problems with caffeine, within a wider set of daily habits and how the caffeinated drink fits into the many far more impactful elements of relaxation, stress, morning and afternoon drinks, bedroom heat, breathing patterns and many other contextual aspects of you, your body and the situation. There is a mass of evidence in studies of sleep behavior that the process of timing, preparing and enjoying your evening drink is more critical than its specific constituents.
“Caffeine-intolerance” is very real for many people and levels of caffeine in your bedtime drink often do have a dramatic impact on sleep. But caffeine-as-villain is too narrow a perspective. It is analogous to a major Swedish study of work that aimed at identifying differences in stress among professions and specific activities. Subjects wore body monitors that tracked their blood pressures, heart beats, perspiration and galvanic responses throughout the day.
The project was abandoned after a few months. The data showed that nothing in their work had even a fraction of the stress created by driving to it. Similarly, the contributions of tea, coffee or herbal brews to quality of sleep are dwarfed by the wider dynamics of your routines and physical makeup. (There’s some evidence that some types of caffeine-intolerance may be caused by genetic variations of the Adenosine A2A receptor gene, in which case, you don’t have any real choices.)
Here’s an impressionistic summary of the scientific research studies on caffeine and sleep. It is very muddly and doesn’t add up to a clear picture of the landscape. One study, for example, looks pretty definitive. It shows that caffeine reduced average sleeping time among its subjects by two hours a night, increased the number of awakenings, and doubled the time of wakefulness.
The caffeine was set at 300 milligrams, to equal the average daily intake, but here delivered in one dissolved dose. There were just six subjects, all middle-aged. The caffeine is the equivalent of 8-12 cups of whole leaf tea at a single sitting. Contextual issues applicable to real tea in a real setting such as the heat of the tea, how long it took to cool and drink, the range of subjects’ ages, and bladder management are entirely absent. All the study really says is that a huge dose of coffee or tea is guaranteed to have an effect.
This pattern comes up again and again in studies. The caffeine is generally a tea extract, pill or powder. This omits other elements of the leaf’s chemistry. For instance, L-theanine compounds seem to have a relaxing impact on the brain. They offset some of the energizing impacts of caffeine.
But they are not included in the study by letting the whole leaf compounds interact. It’s all just caffeine not tea.
And an absurd amount of just caffeine. Most studies treat subjects with a 250-400 mg hit. Of course that extreme input will create extreme outputs. If you make yourself a single cup of whole leaf tea, it will typically contain just 20-40 mg. Studies that use doses of 40 to 80 do show some largely small but consistent sleep disruptions. Many of these are dependent on levels and times of caffeine consumption during the day, with different effects on morning sleepiness, cognitive performance and even finger muscle strengths (500 mg of caffeine doubles it – 12 or more cups of tea; now why does that not seem surprising?) One study concludes that anyone who consumes 500-600 mg of caffeine a day “is likely” to have sleep difficulties. Anyone who does that has more to worry about than taking a nap.
The major limitation of the studies is in many ways their strength: the wide variation in impacts depending on context and person. Here are a few examples that may apply to you – you as an individual reading this post. Going back to the Swedish study where driving dominates anything else, the single most influential factor in getting good sleep is socioeconomic worry: don’t face financial problems and work insecurity and try not to be poor, please.
Large-scale repeated samples and longitudinal analyses show that worry, mood and overall body comfort account for most of sleep disruptions, more than health status. Forces that help build these improve sleep. Poverty is not a controllable factor, alas, but ones that are include lowering the bedroom temperature, for instance (research shows a consistent positive relationship between sound sleep and below average heat), selection of music at night, and breathing exercises.
So, how can tea aid in sleep?
The role of your bedtime drink expands from caffeine-sensitivity to mood and comfort “management.” It’s worth noting that the daytime value of tea has for millennia been seen as its calming and encouragement of meditation, mainly through its rituals and ceremonies. This has been the core of Buddhist tea practice, the Japanese tea ceremony, and the British “let’s all sit down and have a nice cup of tea.”
This doesn’t have to involve more than brewing a special tea in your favorite pot and just taking time out. Exactly what tea or which alternative drink you choose should fit into this context.
Here come the wise old wives’ less savvy offspring armed with much nonsense and less knowledge. They generally discourage all teas except low-caffeine green and lower-caffeine white teas. It is a complete myth to assume that the lighter the tea, the lower the caffeine. Current marketing hype too often claims that white tea is even lower in caffeine than green, because it is lighter in its leaf. The way white tea is harvested and the selectivity of the buds that are plucked makes it often the very opposite, far higher than big, dark, and full black teas. Japanese green teas are higher in caffeine than typical black ones. Overall, the range is typically 40-60 mg for black, down to 20 for green and 12-60 for white teas.
Pick any of them. If you are drinking just one nighttime cup, then 60 will not have a substantial direct disruptive effect and in any case that is small compared to the mood/comfort contribution. For most people, black tea will be a little too brisk and sharpen their senses rather than help them drift into sleepiness. Green teas offer a wide range of flavor, with slightly vegetal ones that are crisp but can be a little too drying, and sweeter and floral brews that are gentle and very satisfying. Some of those will be higher in caffeine – Japanese Sencha for example – but just right for mood: soft and relaxing.
And if you thought herbal teas are better…
Herbal teas can be dangerous choices. They are advertised for their Sleepy-something value and for being caffeine-free and natural. Most are processed for packaging in tea bags. Many meet their promise; they are soothing and aromatic, warming and easy to digest. Their selling messages often rest on the contrast of caffeine-bad/herbal-good distinction.
There’s a lot of herbal bad, though. The very fact that chamomile, valerian, lavender, lemongrass, spearmint and other common ingredients in them have proven health benefits in and of itself is a warning. It means that they interact with the body at the neurological and chemical level; they are not inert. Remember that Lucrezia Borgia’s reputation as a poisoner (more a libel than a likely truth) rested on her herb-gathering and blending skills; her sleepytime brew was for ever.
Many of the ingredients mentioned earlier are powerful. Chamomile has been used since the dynasties of Ancient Egypt for its easing of digestion, antibacterial properties and soothing depressive impacts. Those come with risks of bleeding, severe drowsiness if mixed with alcohol, and significant dangers in pregnancy. Spearmint is healthy in itself but easily affects kidney functions when mixed with a variety of other medications.
Valerian is a marvelous sedative and sleep aid but physicians routinely warn of its many dangers and strongly urge getting specific advice, avoiding its use in conjunction with many medical prescriptions, discontinuing long-term use, and stopping any consumption for two weeks before any surgical treatment. It acts very much like a medical anesthetic.
This statement is commonplace in reviews of valerian: “However, [this and several other herbs] are powerful drugs that should be used only under the consultation of a medical professional, not used casually as a beverage.” Herbal tea can be far more dangerous than caffeine for some people, just as caffeine is for others but both are safe for most individuals. There is no reason then for you to view whole leaf tea as something to avoid at bedtime and herbal tea as safer and more effective.
The trade-offs are compounded by the fact that none of the main herbal sleep aids has been proven to have any measurable effect. The main word summarizing results of research studies is “inconclusive.” But, coming back to the value of a beverage at night in providing warm hydration, a relaxing mood-builder and a pleasant taste, if it works for you, that’s fine. Maybe your reaction is “subjective” but getting to sleep can be as much a matter of mind as body.
Of course, the body part matters. There are many degrees of response to caffeine, ranging from allergic, sensitive and intolerant to dependency and even addiction. Caffeine-intolerance means don’t consume anything that contains it: tea, coffee, chocolate, Exedrin, most soft drinks, Anacin, ice cream, and the like. In most instances, you already know how caffeine affects you, which is probably that it’s not a worry but you have had occasions when you were kept awake from too late a coffee bucket or a “Yes, please” reply to the question “Would you like another slice of this great chocolate gateau?” You’re probably a little concerned about being concerned, warned off from even trying a late night cup of good tea because it seems fine but “everyone” says avoid caffeine after two pm, etc. etc.
Our recommendations of some teas to consider that offer a fine combination of sleep help
White: Silver Needle, expensive but affordable for one cup a day. Choose the best from Yunnan (China), Darjeeling top estates, Sri Lanka.
Gyokuru (Japanese): Very expensive and for occasional drinking. Also high caffeine. But exquisite and a sensory delight – light and rich.
Sencha: pick a good grade. Recommendation is Kagoshima or Uji with very little astringency and not too light or Houjicha which is smoky and leaves a pleasant goodnight aftertaste.
Jasmine Pearl for its smoothness, absence of astringency and floral freshness.
Yunnan Mao Feng for its buttery feel and refreshing light taste.
Oolong: Taiwan Tung Ting that’s fuller than greens and whites but not too much so for bedtime. Adds a smoky flavor that lingers pleasantly.
Black: Don’t be afraid to try a China Keemum or a lighter Indian Darjeeling. Play around with the brewing time to lower the astringency.
Tea is such a pleasure throughout the day. There is no dogmatic reason not to keep it so at night. Yes, caffeine may impose a block on you but that is not a given. Think of tea as part of designing your bedtime mood and routine. Pick your drink on that basis. Your body will let you know if you’ve got it right.
Illustration by Tasneem Amiruddin