How Coffee Can Actually Make You Tired

Coffee is a beloved beverage for many people, providing a much-needed boost of energy and alertness in the morning or during a long day at work.

But did you know that coffee can sometimes make you tired? This article will explore the science behind coffee, its effects on the body, and some other surprising things that coffee can do.

The Science Behind Coffee and Fatigue

Coffee contains caffeine, a stimulant that acts on the central nervous system. When consumed, caffeine blocks the effects of adenosine, a neurotransmitter that promotes sleepiness. This is why coffee can make you feel more awake and alert.

However, the effects of caffeine are different for everyone. Some people are more sensitive to caffeine than others, and for these individuals, even a small amount of coffee can cause jitteriness, anxiety, and other unpleasant side effects.

In extreme cases, caffeine sensitivity can lead to insomnia, characterized by difficulty falling asleep.

It Works Differently for Different People.

Additionally, the effects of caffeine can vary depending on a person’s overall health, caffeine tolerance, and the time of day that they consume coffee. For example, drinking coffee in the evening can interfere with the body’s natural sleep-wake cycle, making it harder to fall asleep at night.

One study found that individuals with high caffeine intake (more than 300 mg per day) were more likely to experience sleep disturbances and daytime sleepiness than those with lower caffeine intake. This suggests that excessive coffee consumption can ultimately lead to fatigue, despite its initial energizing effects.

Other Surprising Effects of Coffee

In addition to its potential to make you tired, coffee has many other effects on the body. Here are a few examples:

Coffee can improve physical performance

Caffeine enhances athletic performance, particularly in endurance sports like running and cycling. This is because caffeine stimulates the central nervous system, allowing the body to utilize fat as a fuel source instead of glycogen. This can help athletes to maintain their energy levels for more extended periods.

Coffee can improve cognitive function

Caffeine has been shown to improve memory, reaction time, and other cognitive abilities. This is thought to be due to caffeine’s effects on the brain, which include increased blood flow and the release of neurotransmitters like dopamine and norepinephrine.

Coffee can have negative effects on health

While moderate coffee consumption (up to 400 mg per day) is generally considered safe, excessive intake can negatively affect health.

For example, high caffeine intake has been linked to an increased risk of osteoporosis, heart palpitations, and digestive issues. Additionally, the roasting process used to make coffee beans produces a chemical called acrylamide, which has been classified as a potential carcinogen.

How to Enjoy Coffee Without the Negative Effects

If you’re a coffee lover but want to avoid the harmful effects of caffeine, there are a few things you can do:

Choose a lower-caffeine option

Some types of coffee, such as decaf or coffee made from Robusta beans, have less caffeine than others. Switching to one of these options can help you enjoy the flavor of coffee without the jitters.

Drink coffee in moderation

Adults’ recommended daily caffeine intake that is considered safe is 400 mg, equivalent to about four cups of coffee. To avoid negative effects on health, it’s essential to stick to this limit and avoid consuming excessive amounts of coffee.

Avoid drinking coffee in the evening

As mentioned earlier, drinking coffee in the evening can interfere with the body’s natural sleep-wake cycle, making it harder to fall asleep at night. If you’re sensitive to caffeine or have trouble sleeping, avoiding coffee in the hours leading up to bedtime is best.


In conclusion, coffee can have a range of effects on the body, from improving alertness and cognitive function to causing fatigue and other negative health effects.

Whether coffee makes you feel energized or tired depends on factors such as your sensitivity to caffeine and the time of day you consume it. To enjoy coffee without the negative effects, it’s important to choose a lower-caffeine option, drink it in moderation, and avoid consuming it in the evenings.