Is Too Much Caffeine Negatively Impacting Your Work Performance?

When we need an extra boost in productivity, many of us reach for a cup of coffee. Whether we’re trying to start the day or pull through a mid-afternoon slump, nearly half of all Australians consume coffee in any given week. Unsurprisingly, Australians who work long hours drink the most coffee - those working 60+ hours per week will drink about 10.1 cups of coffee weekly, whereas those who work 35-39 hours per week will only drink 8.6 cups.

Caffeine can be helpful when consumed in small amounts. At low doses, caffeine can improve alertness, make us more supportive of others in social situations, and help reduce the risk of workplace accidents. It can also improve mood, reduce mental fatigue, and help with attention tasks. And, as most of us have witnessed, caffeine provides the body with a short boost of energy. However, if we drink too much coffee, we can end up hurting our productivity rather than helping it.

Irritability, anxiety, digestive discomfort, inability to focus, and insomnia are all possible side effects of overconsumption. Caffeine also triggers the release of adrenaline, the source of our “fight or flight” response, which favours quick response over rational thinking. When adrenaline levels are high, we’re more likely to let our emotions take over, which can compromise our decision-making skills.

Even if you drink your coffee first thing in the morning, it can interfere with your ability to sleep that night. Caffeine has a half-life of six hours, meaning it takes a full twenty-four hours for it to leave your system completely. If you drink a cup of coffee at eight a.m., 25% of that caffeine will still be in your body by 8 p.m.. If you have an afternoon coffee break, 50% of that caffeine will remain in your system by bedtime. Caffeine in the bloodstream makes it difficult to fall asleep, and disrupts the quality of sleep by reducing REM (rapid eye movement) sleep, which your body needs to fully recuperate. Lack of (or low-quality) sleep leads to reduced self-control and focus, both of which are needed to maintain a high EQ. Reduced REM sleep means you’ll wake up feeling tired, and the first thing you’ll want to do is - you guessed it - reach for a cup of coffee. Then, the cycle starts itself over again. (Read about the importance of sleep in our previous blog post here.)

When it comes to drinking coffee, how much is too much? There doesn’t seem to be a clear consensus - some sources say that 100mg is just the right amount to have a boost without any of the negative side effects; other sources say 200 - 300mg is considered safe, and others advise keeping consumption under 400mg per day. To put that in context, a shot of espresso typically has 60 - 80 mg, and a mug of percolated coffee has 60-120mg, depending on the brew. Of course, like any drug, the tolerated amount will be different for everyone. People who have anxiety should avoid caffeine entirely, though caffeine (in moderation) can be helpful in boosting productivity for those with depression. Body type, weight, and age are determining factors as well. Only you can determine how much caffeine is right for you. Pay attention to your level of alertness, calmness, and ability to make decisions logically as well as to your physical sense of wellbeing.

Timing is almost as important as dosage when it comes to caffeine consumption. While many of us reach for a cup of coffee first thing in the morning, we’re better off waiting until 9:30 a.m. or so. As part of our circadian rhythm, the body produces cortisol to promote alertness, with production peaking between 8 and 9 a.m.. When we combine cortisol and caffeine, the caffeine ends up being less effective and you’ll drink more to feel that jolt of energy. This causes your body to build a tolerance to caffeine, meaning you’ll require more of it to feel any effect. By 9:30 a.m., that first spike of cortisol will begin to subside, and your coffee will be more effective than if you drink it immediately upon waking. Make sure to finish your coffee before 11:30 a.m., so your caffeine intake won’t interfere with your ability to fall asleep that night.

While coffee might be a pleasant part of your morning ritual, you may consider swapping it out for decaf or green tea. If you decide to reduce your caffeine intake, remember that caffeine is technically a drug, and it is physiologically and psychologically addictive. Lower your intake gradually to avoid withdrawal symptoms, which can include headache, fatigue, difficulty concentrating, nausea, depression, and irritability. Remember that moderation is key, and time your caffeinated beverages for maximum benefit and minimal side effects.