Coffee Affection is reader-supported. When you buy through links on our site, we may earn an affiliate commission. Learn more.

What Affects Caffeine Absorption? Health Facts to Know!

person holding white ceramic cup with coffee

Do you enjoy a hot, or cold, cup of coffee to help get you going each morning? If you are not a fan of coffee, do you prefer tea? No matter what your go-to drink is for that energy boost, or to wake you up when you’re feeling tired, it’s the caffeine inside giving you the energy you crave. But have you wondered why some caffeinated beverages, gums, and supplements seem to work in different ways? The answer is caffeine absorption.

Most likely, you’ve taken note of how caffeinated drinks have different effects on people. For some, drinking coffee late at night makes no difference, they can still sleep like a baby. Other people may need to avoid coffee, tea, soda, and even chocolate later in the day or their entire sleep cycle is damaged. While genetics plays a role in caffeine absorption, there are also other factors you should be aware of if you want the most out of your caffeine intake daily. Let’s take a look at those facts so you can better understand how caffeine absorption works.

divider 6

The Basics

Caffeine is a naturally occurring stimulant that is found in coffee beans, tea leaves, certain nuts, and the cacao plant. When we drink or eat something with caffeine, including dietary supplements which normally feature high doses of caffeine, it gives us energy and mental clarity. In most instances, caffeine is absorbed into the bloodstream within 15 to 45 minutes due to its ability to pass through our body’s membranes quickly.

Caffeine is similar to and competes against adenosine, a brain-calming molecule. When caffeine comes out on top of this competition it binds to the receptors in the brain. This is when caffeine truly goes to work by giving us an alert, awake feeling. When caffeine wins the battle with adenosine, our nerve cells react and the calming, or tired feeling adenosine causes slips away.

roasted coffee beans
Image Credit: Alexas_Fotos, Pixabay

Dosage vs Speed

While you may think drinking your morning coffee quicker will kick the caffeine absorption up a notch, this isn’t the case. It takes time for the caffeine you ingest to do its job and get where it needs to go inside the body. Remember, the 15 to 45-minute absorption time frame we mentioned? Chugging a soda or killing two cups of coffee without enjoying them won’t make absorption happen faster. However, the amount of caffeine you take in, or the dosage, does have an effect.

While a cup of coffee has around 95 milligrams of caffeine, many energy drinks on the market offer larger doses. Drinking an energy drink with 200 milligrams of caffeine will give you a major energy boost faster than your morning cup of joe. This is due to the amount of caffeine you’re ingesting, not the speed at which you drink it.

Caffeine Half-Life

We mentioned how long it takes for caffeine to give you the boost you’re looking for but how long does it last? In most cases, caffeine has a half-life of 5 to 7 hours. What is a half-life? This is the time it takes to reduce a substance by half of its original value. So, if you drink a cup of regular coffee with 95 milligrams of caffeine, 5 hours later you’ll still have roughly 47.5 milligrams in your body. This shows that once the caffeine is absorbed, it’s there for a bit.

a woman enjoying a cup of coffee
Image Credit: Ketut Subiyanto, Pexels

Caffeine and Skin Care

You may not expect coffee beans or tea leaves to do anything to your skin, but it does. More and more beauty gurus are using coffee scrubs, soaps featuring caffeine, and even makeup with caffeine found inside. While they enjoy the benefits of clear, revitalized skin they are also reaping the benefits of caffeine skin absorption.

While caffeine has natural sunscreen effects and works as an inflammatory, the amount absorbed through the skin is determined mostly by the length of time the product is left on. If you use caffeine products for bathing or face scrubbing, you’ll get a bit of a dose before it is washed off. If caffeine is present in a product you plan on wearing on the skin all day, you may get more caffeine absorbed into your skin than you’d expect.

Lifestyle Choices

Yes, our lifestyle choices affect caffeine’s ability to absorb into our bloodstream. It is believed that smokers metabolize caffeine more quickly than a non-smoker. It is even believed that certain oral contraceptives can alter how caffeine acts inside our bodies. This is why it is so difficult to pinpoint how a person will react to caffeine. Everyone is different so caffeine absorption will alter according to its host.

divider 2

Final Thoughts

As you can see, there is a lot to know about caffeine absorption. Genetics, lifestyle choices, and dosage all factor in when it comes to how quickly and how much caffeine will make its way into your bloodstream once you’ve ingested it. Keep this in mind when you sit down to drink your next morning cup of coffee or cup of tea. There’s no rush. The caffeine will give you the boost and clarity you’re hoping for. Simply sit back and enjoy.

Featured Image Credit: Olenka Sergienko, Pexels


Melissa Gunter

Melissa has been a fan of coffee since the first sip she stole from her Granny's cup when she was just a girl. Now, she spends each morning writing with a hot cup of coffee at her side. With a love of sweet and creamy bliss, Melissa and her daughter, Amber, stop by and try out every local coffee shop they see. Neither are afraid to try something new and have a long list of favorite coffee beverages they simply can't do without. When she's not freelance writing about her 2 passions, coffee, and pets, Melissa spends her time with her husband, 2 kids, and 5 fur babies. She also loves diving into the fiction world under her pen name, Rena Marin. If she isn't at the laptop or with the family, Melissa is out enjoying the mountains of East Tennessee she calls home.

Read more

Related posts

Other Categories