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Things to know about the world’s favourite performance enhancing substance.

  • Caffeine helps by improving performance when alertness is low.
  •  It helps us overcome the after-lunch dip (caused by our body clock, not by eating!)
  • Usually takes between 15 and 30 minutes to become effective.
  • Effects last in our bodies for up to 4 hours, so don’t drink caffeine too close to bedtime. Even if we don’t think that the caffeine is impacting our sleep, it reduces the quality, so we can feel more tired the next day, needing more caffeine.
  • We build up a tolerance to caffeine, so it is most effective when you don’t drink very much (less than 120mg a day is a good aim.)
  • Average caffeine quantities in some popular drinks:

Red Bull (8 oz can) 80mg
Starbucks cold brew coffee (16 oz) 200mg
Starbucks Grande Caffe Latte (16 oz) 150mg
Black tea (8 oz) 42mg
5 hour energy (2oz) 200mg
Berocca (8oz) 90mg
Black Label Brewed Coffee (12 oz) 1555mg
Coca-Cola Classic (12oz) 34mg
Instant coffee (8oz) 57mg

Up to 400mg a day is not considered harmful in adults but, if you keep your consumption below 120mg a day, then you can keep your caffeine tolerance low, so caffeine will work for you when you need it.

Use our Caffeine Calculator to check your average daily intake of caffeine and what that means.