If coffee, tea, or some other caffeinated beverage is part of your daily
routine, you’re far from alone. A study found that

85 percent

of all Americans consume at least one beverage containing caffeine every
day.

Here’s the lowdown on it, the ways it effects your body, and how you can
safely take advantage of its ability to put some pep in your step.

Pure caffeine

Caffeine is

a bitter substance

that is naturally found in more than 60 plants, including tea leaves and
coffee and cocoa beans. It can also be produced synthetically in a lab. In
its pure processed or manufactured form, caffeine is

a white powder

that can be added to food, beverages, and medicines.

How your body processes caffeine

The caffeine in beverages is quickly absorbed by your stomach. It then
dissolves in your body’s fat and water molecules and crosses into your
brain, where it affects your central nervous system.

Caffeine usually reaches its peak level in your blood in 15 minutes to two
hours, but it can remain in your system for much longer. That’s why the
recommended cut-off time for consuming anything containing caffeine is at
least

eight hours before bedtime.

Why caffeine is a stimulant

Caffeine provides a quick energy boost because it stimulates your central
nervous system.

When you’re awake, your body produces a chemical called

adenosine. The chemical binds to cells in your brain called receptors, slowing your
neural activity, and making your feel tired.

Caffeine binds to

the same receptors

as adenosine, but has no effect on brain activity. However, the number of
receptors available for adenosine to bind to are reduced by the caffeine,
which causes your neural activity to speed up. It also causes a relative
increase in chemicals that benefit your

mood and brain functioning, such as dopamine and norepinephrine.

Caffeine consumption guidelines

Consuming up to 400 milligrams of caffeine a day is generally safe for most
adults. To put this in perspective, that’s about:

• Four cups of coffee
• Eight cups of tea
• 10 cans of cola
• Five-and-a-half cups of a typical energy drink
• A little less than two full energy shots

Consuming too much caffeine

can make you anxious, jittery, and/or nauseous. It can also speed up your
heart rate, upset your stomach, and cause dehydration, headaches, and/or
insomnia. Rapidly consuming an excessive amount of caffeine (approximately
1,200 milligrams or 0.15 tablespoons of pure caffeine) can cause seizures.

Consuming too much caffeine can even be fatal, although this happens very rarely.

Ask a health care provider about limiting your caffeine consumption if you:

• Are pregnant or breastfeeding
• Have a sleep disorder
• Experience anxiety
• Get migraines or other headaches
• Have arrhythmia and/or high blood pressure
• Take medicines and/or supplements it might

interact

with

How to cut back on caffeine

Cutting back on caffeine should be viewed as a process. Quitting caffeine
cold turkey can cause miserable withdrawal symptoms, such as headaches,
drowsiness, irritability, trouble concentrating, and nausea.

The best way to avoid these symptoms is to gradually reduce your daily
caffeine intake. If you drink four cups of coffee every day, begin by
limiting yourself to only three cups or replacing the fourth cup with decaf.
After a week goes by, try cutting out another cup.

You can also try

swapping highly caffeinated drinks with tea. Black tea has about half the amount of caffeine found in a typical cup of
coffee, and green tea has even less.

Staying hydrated can also help you successfully kick a caffeine habit.
Replacing cold caffeinated beverages with water can make the transition
easier and will help your body naturally flush the caffeine out of your
system.

The bottom line

Caffeine can have pleasant and uplifting effects when it’s consumed in
moderation. If you’re experiencing
any of the side effects associated with consuming too much caffeine, you may
want to consider cutting back gradually or swapping out your current
beverage of choice with a lower caffeine option.