Wake Up and Don’t Smell the Coffee

The only known function of sleep is to cure sleepiness and the best time to drink a cup of coffee is 10.30am. The fact that we spend about a third of our time asleep, and that sleep deprivation can have disastrous effects ultimately leading to death, demonstrate the importance of sleep. But what is the neuroscience about waking up and coffee?

Waking early is one of my favourite things in the world. But I don’t now start the day with a coffee (or diet coke in my case). It does the opposite of what you think. If it is light outside, start by opening the curtains and bask in sunlight; drink a pint of water. The morning time is brilliant and quiet, as the world hasn’t begun stirring, the perfect time for meditation, writing, exercise and some quiet reading. If you do some research you will find that many successful CEOs are up at the crack of dawn. It is in the DNA of leaders. If we want to be successful, we need to be working when others are not. Waking early can give you an hour or three of extra time for focus and creativity. While you could do those things later in the day, most people don’t (with exceptions of course).

The key to getting up early is an understanding of chronopharmacology, coffee, cortisol and zeitgebers. Chronopharmacology can be defined as the study of the interaction of biological rhythms and drug action. One of the most important biological rhythms is your circadian clock. If you combine the latest neuroscience with improved imaging techniques like EEG, PET and fMRI, along with high computational power have led to an increasingly greater understanding of the mechanisms underlying sleep and waking up.

A zeitgeber is a term used in chronobiology for describing an environmental stimulus that influences biological rhythms. The term zeitgeber (German for "time giver" or synchroniser) was first used by Jürgen Aschoff, one of the founders of the field of chronobiology. His work demonstrated the existence of endogenous (internal) biological clocks, which synchronise biological rhythms. In addition, he found that certain external cues, which he called zeitgebers, influence the timing of these internal clocks.

It has been known for a long time that light is a strong zeitgeber. In the case of mammals, light is by far the most powerful. Following the discovery of connections between the retina and hypothalamus (the retinohypothalamic tract), investigations were aimed at the hypothalamus as the putative master clock. Since light is the strongest zeitgeber, open the curtains and let the light flood in for an hour. This would allow for stronger signals to be sent along the retinohypothalamic tract, thus increasing your morning cortisol production at a faster rate.The best times to drink coffee are when your cortisol levels naturally dip. These are, in fact, traditional coffee break times (further details can be found here http://www.ncbi.nlm.nih.gov/pubmed/18854200). The best time to drink a cup of coffee to get your daily hit of caffeine is between 9.30am and 11.30am, according to neuroscientists It may seem that a cup of strong coffee first thing in the morning is the best way to get yourself going, but in fact waiting until later may be better.

So the best time to drink a cup of coffee: 10.30am.

This is due to the way caffeine interacts with a key hormone – called cortisol – which helps to regulate the body’s own internal clock and promotes alertness. Cortisol levels are naturally high shortly after wake up and can remain high for up to an hour afterwards – with the average peak being between 8am and 9am. The effects of caffeine consumption at times of peak cortisol levels actually diminishes the effectiveness of the additional stimulation. Worse still, by consuming caffeine when it is not needed, your body will build a faster tolerance to it, and the buzz you get will greatly diminish.

Cortisol is also considered a stress-related hormone and consumption of caffeine has been shown to increase the production of cortisol when timed at periods of peak cortisol levels. An increased tolerance for caffeine can therefore lead to heightened cortisol levels which can disturb circadian rhythms and have other deleterious effects on your health.The times of peak cortisol levels in most people are between 8-9 am, 12-1 pm and 5:30-6:30 pm. Therefore, timing your coffee breaks between 9:30-11:30 and 1:30 and 5:00 takes advantage of the dips in your cortisol levels when you need a boost the most.

Put this way, the traditional idea of a coffee break makes a lot of sense. Cortisol for these individuals is likely very low compared to when sunlight dramatically increases in the morning. However, there is a phenomenon called the Cortisol Awakening Response (CAR) that results in an approximate 50% increase in cortisol upon awakening. This would suggest that even these individuals would not need caffeine immediately upon awakening either.

Be Amazing Every Day

Inouye, S.T., and Kawamura, H. (1979). Persistence of circadian rhythmicity in a mammalian hypothalamic “island” containing the suprachiasmatic nucleus Proceedings of the National Academy of Sciences of the United States of America DOI: 10.1073/pnas.76.11.5962