British Coffee Association - Alertness


Coffee is well known for containing caffeine, which is a mild central nervous system stimulant 1,2. Drinking coffee can therefore have positive effects on an individual’s alertness and concentration so aiding better performance - this has been shown to be of benefit when an individual is feeling tired or lethargic 3.

Alleviating Driver Fatigue

Research 4,5,6 has demonstrated, quite clearly, that a couple of cups of coffee and a short nap are the most effective way of alleviating driver fatigue. Many road traffic accidents occur as a result of a driver falling asleep at the wheel so any measure that can be taken to reduce the incidence of this, including drinking coffee, can only be for the good. The UK Department of Transport’s Think! Road Safety Campaign gives advice including, ‘Drink two cups of coffee or a high-caffeine drink and have a rest for 10-15 minutes to allow the caffeine to kick in’.

Post Lunch Dip

Business colleagues solving a problemAfter lunch it is quite usual to experience what is known as `the post lunch dip’, this is when our bodies' natural rhythms slow down and as a result we become less alert and find it difficult to concentrate. The caffeine contained in a couple of cups of coffee is sufficient to raise levels of alertness, and increase our concentration, enabling those at work to keep going until the end of the working day 7.

Night Shift Work

With an increase in the ’24 hour society’ it is inevitable that more and more people will be required to work through the night and research 8,9 has shown that these individuals may benefit from a couple of cups of coffee during the evening to help them concentrate better during the early hours of the morning. Importantly, neither the time taken to fall asleep, nor the quality of sleep, were affected by coffee consumed during the night shift.

Common Cold

Research 10 from Bristol University has demonstrated that drinking coffee has been shown to add a `feel good’ factor and lift some of the sluggish symptoms that are the common after-effects of a cold. Volunteers were tested when healthy and then again when they had a cold. The results were assessed and coffee increased alertness and performance of the sick volunteers to the same level as the healthy group.

Physical Performance

Caffeine is widely reported 11,12,13 to be an ergogenic aid i.e. a substance that improves the capacity to do work or exercise. It has been shown that caffeine consumption can improve athletic performance in numerous endurance events including swimming, cycling and women’s tennis.


Coffee is one of the most heavily researched commodities in the world today and the wealth of scientific evidence suggests that moderate coffee consumption, of four to five cups per day, can contribute to a healthy, balanced diet for the general population and may confer health benefits. Pregnant women should however moderate their intake following the guidelines issued by the Food Standards Agency, to 200mg caffeine per day from all sources.

The caffeine contained in a couple of cups of coffee (approx 120mg) increases alertness and performance, aids concentration and alleviates some of the sluggish symptoms associated with the common cold.

1. Smith AP. Human Psychopharmacology Clinical and Experimental, 2005; 20: 441-445.
2. Dorea et al. British Journal of Nutrition, 2005; 93: 773-782.
3. Nehlig A (2010). Is Caffeine a Cognitive Enhancer? J Alzheimers Dis, 20, S1: 85-94.
4. Brunyé TT, et al. Caffeine modulates attention network function. Brain Cogn, 2010; 72:181-8.
5. Horne & Reyner. Psychophysiology, Volume 34, 1997.
6. Brice CF and Smith AP. Psychopharmacology, Volume 16, 2001.
7. Smith AP, et al. Effects of caffeine given before and after lunch on sustained attention. Neuropsychobiology, 1991;23:160-3.
8. Smith AP. Caffeine at work. Hum Psychopharmacol, 2005; 20:441-5.
9. Smith AP. Caffeine, cognitive failures and health in a non-working community sample. Hum Psychopharmacol, 2009;24:29-34.
10. Smith AP. Neuropsychobiology, Volume 27, 1993.
11. Goldstein E.R. et al. J. International Society of Sports Nutrition Position Stand: caffeine and performance, 2010.
12. Ganio M. S. et al. Effect of Caffeine on Sport-Specific Endurance Performance: A Systematic Review. J Strength and Conditioning Research, 2009; 23.
13. Astorino T.A. et al. J. Efficacy of Acute Caffeine Ingestion for short-term high-intensity exercise performance: A Systematic Review. Strength and Conditioning Research, 2009; 24 (1): 257-265.