Faster, But Not Smarter

There is nothing like waking up in the morning and brewing some fresh coffee. It is a ritual that I’ve included as part of my morning routine for quite some time. I measure my coffee beans with a gram scale, I make sure the water is properly filtered and re-mineralized for the best flavor. I buy my coffee beans fresh from a local roster and try to select a “water process” to minimize my exposure to mycotoxins (although, in the US this is not really a concern, but better safe than sorry).

Within the Paleo community, we love to sing the praises of coffee. For example, coffee helps protect DNA from spontaneous DNA breaks that lead to random mutations. [1] The problem is that as humans, we love to “cherry pick” the information that will support our views. Could there be adverse effects from consuming large amounts of caffeine?  For this post, I want to delve into the information that warn us against the overconsumption of caffeine. Please, bear with me.

the research 

A study published in 2002 investigated the effects on healthy adults receiving caffeine dosages ranging from 90 mg to 250 mg. [2] The subjects did improve in cognitive performance, in a dose dependent matter. The problem is that at higher concentrations of caffeine, they also experienced dangerous spikes in blood pressure.  

To put it on perspective, a short (small) “Bucks” coffee packs a whooping 180 mg of caffeine (double the effective dose). A tall (medium) packs 260 mg of caffeine, more than the dangerous dose administered to the subjects! 

Average content of caffeine in coffee from a famous coffee chain.

Average content of caffeine in coffee from a famous coffee chain.

Deeper into the data

A study aptly named “Faster, not Smarter”, aimed to investigate the effects of caffeine and perception of alertness. The researchers tested these effects in people that consume caffeine periodically and people that abstain from caffeine consumption. [3] The study found that people who abstain from caffeine did find an increase in response-time with consumption of caffeine. Caffeine reduced their perception of sleepiness and subjects gained speed in simple motor tasks. This was attributed to an increase in jitteriness (they were more likely to "trigger" their response). In comparison, the people who regularly consume caffeine had their motor skills improve to levels before their caffeine deprivation.

This is a visual representation of the results from Faster but not smarter: Effects of caffeine and caffeine withdrawal on alertness and performance. [3] This graph was created as a visual tool, and does not represent actual results from the paper.

This is a visual representation of the results from Faster but not smarter: Effects of caffeine and caffeine withdrawal on alertness and performance. [3] This graph was created as a visual tool, and does not represent actual results from the paper.

To quote the study:

“increase in mental alertness experienced by medium-high caffeine consumers after taking caffeine,  and the associated improvement in mental performance,  represent a return to the normal state of affairs (i.e. reversal of adverse effects of caffeine withdrawal) rather than an enhancement to above the normal state.”

In other words, the participants that are habitual caffeine consumers would have had similar results if they had abstained from caffeine consumption. Their reliance on caffeine made their performance return to baseline dependent on the consumption of caffeine. The non-caffeine consumers had an increase of response time, but not because they were more aware, their jitteriness made them quicker to react. They were faster, but not smarter.  

The physiology of coffee consumption

Caffeine increases the release of catecholamines such as epinephrine, dopamine and norepinephrine, there are all excitatory compounds that are responsible for our “fight or fight response”. They are also responsible for the feeling of alertness or jitteriness associated with caffeine consumption. [4] 

A single dose of 300mg can exacerbate symptoms of anxiety. A dose of 400mg can trigger panic attacks in people that are susceptible to them, when paired with a stressful task. [5] 

When do people consume caffeine? 

Now, think back at when people tend to consume caffeine. As a society that values going “above and beyond” without regard to our own health, we turn to caffeinated beverages when we are sleep deprived, when we are stressed or when we have a stressful day or task to complete. This creates the perfect storm that masks the need for sleep, increases our stress response and makes the task completion faster, but not better.

People consume caffeine in order to ameliorate their sleep deprivation symptoms. The problem is that consumption of caffeine is associated with decreased time in bed and poor sleep. [6] Improved sleep hygiene might help reduce the reliability on caffeine.

In addition, having a caffeine dependence could stem from a hypothalamus-pituitary-thyroid (HPA axis) dysfunction. Thus, you need an extra boost of catecholamines that can be acquired by caffeine. In fact, a study found that chronic fatigue syndrome was associated with lower levels of cortisol. [7]

“A central characteristic of the previous documented attenuation of the HPA axis in CFS is reduced responsivity, resulting in weakened cortisol response to common daily stressors (such as awakening), and a flattened cortisol diurnal curve”

Strategies for Caffeine Consumption

I try to go without coffee for two weeks, once or twice per year. At the same time, I work on my sleep hygiene and stress reductions. I never experience any effects of withdrawal, and I continue my morning ritual by drinking decaffeinated tea. Roasted dandelion tea or cocoa tea, are very good substitutes for coffee. Remember, even decaffeinated coffee, has trace levels of caffeine.

When I reintroduce coffee, I try to decrease my caffeine consumption to levels of minimum dose response (90mg of caffeine), this is to take advantage of the alertness benefits of caffeine without going into the danger zone of hypertension (above 180 mg). This is about one small cup of coffee per day. Another strategy I use is to consume caffeine earlier in the morning to prevent sleep disturbances caused by an increase of cortisol late in the day.

Coffee should not be used as crutch to return to “baseline” performance. If you enjoy the taste of coffee, and see it as part of your morning ritual, you can continue drinking it! Coffee is chock full of antioxidants and has even shown to prevent DNA rupture. But if you are using coffee to increase your alertness after poor sleep, you might be digging a deeper hole without improving performance. Instead of relying on caffeine for your perceived alertness, cover your bases with better sleep hygiene, stress reduction and meditation. If you believe that your fatigue symptoms are caused by more than just lack of sleep, consult with a practitioner to correct the underlying cause of your fatigue and decreased alertness.




1.       Bakuradze T, Lang R, Hofmann T, et al. Consumption of a dark roast coffee decreases the level of spontaneous DNA strand breaks: a randomized controlled trial. Eur J Nutr. 2015;54(1):149-156. doi:10.1007/s00394-014-0696-x.

2.       Kourtidou-Papadeli C, Papadelis C, Louizos AL, Guiba-Tziampiri O. Maximum cognitive performance and physiological time trend measurements after caffeine intake. Brain Res Cogn Brain Res. 2002;13(3):407-415. Accessed September 14, 2016.

3.       Rogers PJ, Heatherley S V., Mullings EL, Smith JE. Faster but not smarter: Effects of caffeine and caffeine withdrawal on alertness and performance. Psychopharmacology (Berl). 2013;226(2):229-240. doi:10.1007/s00213-012-2889-4.

4.       Yamada Y, Nakazato Y, Ohga A. The mode of action of caffeine on catecholamine release from perfused adrenal glands of cat. Br J Pharmacol. 1989;98(2):351-356. Accessed October 30, 2016.

5.       Persad LAB. Energy drinks and the neurophysiological impact of caffeine. Front Neurosci. 2011;5:116. doi:10.3389/fnins.2011.00116.

6.       Watson EJ, Coates AM, Kohler M, Banks S. Caffeine Consumption and Sleep Quality in Australian Adults. Nutrients. 2016;8(8). doi:10.3390/nu8080479.

7.       Tsigos C, Chrousos GP. Hypothalamic–pituitary–adrenal axis, neuroendocrine factors and stress. J Psychosom Res. 2002;53(4):865-871. doi:10.1016/S0022-3999(02)00429-4.