Caffeine gives you a boost of energy and may lower your risk of certain conditions. However, consuming too much can lead to less desirable effects, such as headaches, confusion, and high blood pressure.
Many of us rely on a morning cup of coffee or a jolt of caffeine in the afternoon to help us get through the day. In fact, research suggests that approximately 69% of Americans consume at least 1 caffeinated beverage daily.
But caffeine does so much more than just keeping you awake. It’s a central nervous system stimulant that affects your body in numerous ways.
Knowing the symptoms of caffeine and its long-term effects on your body may make you think twice about having that fourth cup of coffee. Read on to learn more about these effects.
Caffeine acts as a central nervous system stimulant. When it reaches your brain, the most noticeable effect is alertness. You’ll feel more awake and less tired, so it’s a common ingredient in medications to treat or manage drowsiness, headaches, and migraine attacks.
Additionally, studies have found that caffeine may help with processing speeds and memory, suggesting that moderate intake may help with cognitive (thinking) function.
In fact, research from 2020 found that people who drink moderate amounts of coffee (1 to 4 cups) and green tea (3 to 10 cups) have a lower risk of developing dementia and cognitive decline.
However, when caffeine is consumed excessively, it can lead to cognitive side effects. For example, too much of the compound can cause headaches, which are particularly prominent
The blood vessels in your brain become used to caffeine’s effects, so if you suddenly stop consuming this compound, it can cause a headache.
Other symptoms of caffeine withdrawal include:
In some people, sudden withdrawal may cause tremors.
Although it’s extremely rare, it’s also possible to overdose on caffeine. Symptoms of an overdose include:
A caffeine overdose can also result in death due to convulsions. Overdosing occurs by consuming large amounts of caffeine, most often in energy drinks or diet pills.
Caffeine increases the amount of acid in your stomach, which may cause heartburn or an upset stomach. Extra caffeine doesn’t get stored in your body either — it’s processed in the liver and exits through your urine. This is why you might have an increase in urination shortly after having caffeine.
If you have experience with stomach problems, like acid reflux or ulcers, ask your doctor if it’s okay for you to have caffeine.
Caffeine is absorbed from your stomach and reaches its highest levels in your bloodstream in under an hour.
This compound can temporarily raise blood pressure. This effect is thought to be related to either an increase in adrenaline or a temporary block on the hormones that naturally widen arteries.
In most people, there is no long-term effect on blood pressure, but if you have irregular heart rhythms, caffeine may make your heart work harder.
If you have high blood pressure (hypertension) or heart-related problems, ask your doctor if caffeine is safe for you to consume.
An overdose of caffeine may cause rapid or irregular heartbeat and breathing issues. In rare cases, a caffeine overdose can result in death due to convulsions or irregular heartbeat.
Caffeine in large amounts may interfere with calcium absorption and metabolism, contributing to bone thinning known as osteoporosis. If you consume too much of this compound, it may also cause your muscles to twitch.
If experiencing caffeine withdrawal, a symptom may include achy muscles.
Caffeine travels within the bloodstream and crosses the placenta into the bloodstream of the fetus. Since it’s a stimulant, it can cause fetal heart rate and metabolism to increase.
Excessive caffeine consumption during pregnancy has been linked to slowed fetal growth and an increased risk of pregnancy loss. While moderate intake is generally considered safe, caution is still advised.
The American College of Obstetricians and Gynecologists recommends limiting caffeine intake to no more than 200 milligrams (mg) per day—about the amount in one 12-ounce cup of coffee.
However, some studies suggest that even lower amounts, such as 100 mg per day, may be associated with a higher risk of miscarriage and developmental issues.
Given these concerns, it’s important to consult your doctor to determine a safe caffeine limit during pregnancy.
According to the Food & Drug Administration (FDA), it’s safe for most healthy adults to consume up to
If you’re using a mug or getting your fix at a coffee house, you’re likely drinking 16 ounces or more, so reading labels is important.
As you consume the same amount of caffeine daily, your body develops a tolerance to it. Other factors, like your age, body mass, and overall health, can also determine your tolerance to this stimulant.
If you want to reduce the amount of caffeine you consume, it’s best to do so slowly.
Research suggests caffeine can affect nearly every aspect of the body. When consumed in moderate amounts (400 mg or less), caffeine has been found to have protective effects on the brain.
However, when overconsumed, it can lead to headaches, upset stomach, anxiety, muscle twitches, and more. If you have a medical condition, including migraine or digestive issues, it’s best to speak with a doctor about your recommended caffeine consumption.