Why do you Feel Sleepy After Drinking Coffee?
It doesn’t take rocket science to understand why millions of people reach for the coffee pot to get them started on the right foot each day. It’s the same reason they reach again and again and again throughout the afternoon and sometimes into the evening. In the United States, the biggest dietary source of caffeine is coffee. The caffeine in coffee boosts energy levels and makes us feel sharper. Add in the health benefits and uber satisfying flavor, and it’s no shocker that over 50 percent of Americans drink coffee as part of their daily routine.
But not everyone reacts to caffeine in the same way. As odd as it sounds, instead of the caffeine giving you that relatively quick jolt of energy, some people may actually feel tired—or even experience a caffeine crash—after just one cup.
So if you've been drinking coffee all day but you are still having trouble keeping your eyes open and are jonesing to take a nap right on your desk, hold the (coffee) press—it may not actually be the coffee that is making you feel tired.
7 Reasons Why You Feel Sleepy After Coffee
1. Adenosine will make you sleepy when the caffeine wears off.
Adenosine is a neurotransmitter in our central nervous system that causes fatigue when you aren’t receiving enough to your brain. The caffeine in coffee blocks adenosine receptors in your brain from receiving it. While preventing your brain from receiving adenosine, your body is still producing the neurotransmitter. Because of this, once the caffeine wears off, you have a build-up of adenosine still trying to attach itself to the receptors, and that’s what makes you sleepy.
2. You may be building up a tolerance to coffee.
If you drink a number of cups of coffee each day as part of your normal routine, then it’s likely you have built up a tolerance that keeps you from feeling energized, alert and ready to hammer through your day! Since the caffeine blocks the effects of adenosine, a regular dose of caffeine might mean your body starts to produce more adenosine receptors as a response. So in theory, the more receptors you produce, the less the coffee works as a pick-me-up over time.
3. Choosing coffee vs. water may be making you feel dehydrated.
Since coffee is a natural diuretic, you may have noticed peeing is your best friend when you consume a cup of Joe. That often makes people believe that drinking coffee leads to dehydration. That’s not really true for most people who drink coffee. It really doesn’t act any different than other beverages. The problem occurs when you are drinking coffee instead of water.
So if that describes your behavior—or if you are part of the minority of people that simply have a more active bladder in reaction to coffee, then you may go down a black hole of a dehydration cycle that does eventually make you more tired. Here’s what it looks like:
- Every time you go to the bathroom, your body is losing water.
- Once your body loses water, your blood thickens.
- Thicker blood moves more slowly through your arteries and veins, much like thick molasses in a slow drip.
- As a result of your blood slowing down, less oxygen is delivered to your body.
- Less oxygen causes you to become sluggish and lazy.
- When we feel sluggish and lazy, what better way to amp up again by reaching for more coffee. And the cycle begins again.
Try to consume a glass of water for every cup of coffee you consume. This will help to maximize the effects of sleepiness as it will keep you hydrated and help you enjoy your caffeinated experience.
4. Caffeine can trigger a stress response.
When we drink coffee, the caffeine prompts our bodies to produce a hormone called cortisol, the same chemical we produce when we’re stressed out or scared. (That’s why it’s called the stress hormone.) Elevated levels of cortisol can make you feel alert and keep you up at night, but increased cortisol can also lead to feeling super tired later on in the day.
5. If you're into sweet additives, you'll be the one falling into a deep sleep.
While you’re satisfying your sweet tooth, try thinking about that sugar crash that’s coming soon to a body near you. Sugar is processed much more quickly than coffee and leaves you without energy after it’s used up by your body. If you like a little coffee with your sugar, you may actually be experiencing a sugar rush and crash rather than a caffeine-boost.
6. The dairy and creamers may be causing drowsiness.
An amino acid called tryptophan is in the milk you may be adding to your coffee. Even though it’s a relatively low percentage, tryptophan has been linked to sleepiness. So try swapping out the dairy in your coffee with a plant-based option—or save your waistline and forget it all together. If you notice you feel more alert, then save the milk for winding down at night instead.
7. There could be mold in your coffee.
As disgusting as it sounds, if you’re sleepy after drinking coffee, it could be due to a type of mold in some coffee beans called mycotoxins that have been linked to fatigue. Fatigue could be the least of your worries over time, however. Some studies show that the coffee contamination can cause liver and kidney tumors and is considered carcinogenic to humans. That’s another great reason to watch those labels and only reach for the Certified Organic Death Wish Coffee beans.
Reaper's Pro Tip: Keep your coffee fresh-to-death by keeping it in an opaque airtight canister.
If you’re part of the rare breed that dozes off after your coffee and you’re looking for a quick fix, here’s some advice: You don’t have to give up coffee, just listen to your body. Go easy on the added creams and sugars too. And since water is so good for our general health, make sure you drink a cup of water for every cup of coffee you enjoy. One final note: Coffee isn’t the only beverage that contains caffeine. Sodas, energy boosters and even some pain relievers offer a kick of caffeine. So make sure you’re keeping track of your total caffeine intake. It may not be coffee’s fault at all.
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