Coffee is one of the world’s most widely used stimulants, and it’s well known for its ability to make you feel awake, energized, and motivated. It’s consumed by millions of Americans every day to get a jolt of energy in the morning and throughout the day as a quick pick-me-up. Why, then, can it also make you tired?
Not everyone is affected by coffee the same way, and if you’re someone who feels drowsy after a cup of two of coffee, you’re not alone. Below, we’re going to go over some of the common reasons why coffee might be making you feel tired instead of awake.
To solve the mystery of why coffee makes you sleepy, you should first consider what, if anything, you put in your coffee. Black coffee is free of sugar, of course, but many people add milk, cream, sugar, or sugary creamers to their coffee. These additives pack in calories but also a lot of sugar.
According to this article from Sanford Health, increased levels of sugar in your bloodstream trigger a spike of insulin, which tells the body to use the sugar or store it away. This increase in insulin leads to the sugar in your blood to drop even below an average level, and the lack of sugar readily available for use in your blood, in turn, causes decreased energy.
If you typically add sugar or sugary creamers to your coffee, try cutting back or only adding milk to limit the tired feeling you may be getting from your sugar crash.
Caffeine Blocks Adenosine
Maybe you already drink black coffee or don’t use sugar at all. If that’s the case, then a particular effect of caffeine on your neurotransmitters may be the culprit for your post-coffee sleepiness.
Adenosine is a chemical transmitted into your brain that is directly related to your sleep-wake cycle, commonly referred to as your circadian rhythm. This research article published on PubMed explains that your adenosine levels increase throughout the day until you go to sleep. It’s believed that an abundance of adenosine is directly related to feelings of sleepiness.
Caffeine blocks adenosine receptors in your brain, which causes a buildup of adenosine in your body just like you would have naturally before going to sleep. This heightened level of the neurotransmitter may be leading to a natural reaction in your body to feel tired.
It May Be Dehydration
Most coffee drinkers know that caffeine normally increases the frequency at which you urinate. This is because this stimulant is a natural diuretic, meaning it makes you pass more water than usual.
This article from WebMD explains that dehydration can be a leading cause of feeling tired. The main issue with dehydration is that there isn’t enough water diluted in your blood. Thicker blood means your heart has to pump more, and your muscles get less oxygenated blood for energy.
The take-away is that coffee can cause your body to work harder to get oxygen transported, leading to feelings of tiredness, especially if your muscles are underfed. To fix this, drink water before and after your coffee, and make sure you get the recommended amount of water each day.
Caffeine Can Cause Stress
Coffee drinkers often report that they feel an increased level of stress or urgency after consuming caffeine, and the reason, according to this research paper, is that it naturally increases levels of adrenaline in your body.
Adrenaline can cause increased heart rate and blood pressure, and it’s the hormone responsible for your body’s fight-or-flight response, meaning it prepares you for action. The heightened levels of focus, along with the spikes in heart rate adrenaline can cause, can lead to tired feelings.
If you think this might be the cause of your sleepiness, you can try consuming less coffee each day or try spreading out your coffee consumption over a more extended period of time.
The Bottom Line
Coffee affects everyone differently, and while it may wake some people up and get them ready to take on the day, your morning cup may be making you sleepy. Some of the most common reasons are a sugar crash if you add sugar or sugary creamers to your coffee, the fact that caffeine blocks adenosine in your brain, dehydration resulting from coffee consumption, and increased stress in response to caffeine.
It can be a bit of a bummer to drink a stimulant and quickly feel tired instead of energized. Hopefully, now you understand why it might be happening to you and how to prevent it from occurring in the future. Why does coffee make me tired? Now you know!