Low to moderate doses of caffeine (50–300 mg) may cause increased alertness, energy, and ability to concentrate, while higher doses may have negative effects such as anxiety, restlessness, insomnia, and increased heart rate. [2] Still, the cumulative research on coffee points in the direction of a health benefit.
Studies have found caffeine can do both good and harm. People who regularly drink coffee may be less likely to develop chronic illnesses, such as cardiovascular disease, diabetes, Parkinson's disease and some cancers. A few studies suggest they are less likely to die from heart disease and other illnesses.
“For most people, moderate coffee consumption can be incorporated into a healthy diet.” Hu said that moderate coffee intake—about 2–5 cups a day—is linked to a lower likelihood of type 2 diabetes, heart disease, liver and endometrial cancers, Parkinson's disease, and depression.
Low to moderate doses of caffeine (50–300 mg) may cause increased alertness, energy, and ability to concentrate, while higher doses may have negative effects such as anxiety, restlessness, insomnia, and increased heart rate. [2] Still, the cumulative research on coffee points in the direction of a health benefit.
In addition, caffeine has many positive actions on the brain. It can increase alertness and well-being, help concentration, improve mood and limit depression.
People most commonly use caffeine for mental alertness, headache, migraine, athletic performance, memory, and obesity. It is also used for asthma, gallbladder disease, ADHD, low blood pressure, depression, and many other conditions, but there is no good scientific evidence to support most of these other uses.
While there is often concern about the links between caffeine and heart health, a moderate amount of tea or coffee (four or five cups a day) should be fine for most people. Research shows that this level of caffeine intake shouldn't be detrimental to your heart health, affect your cholesterol levels or heart rhythm.
Healthiest Energy Drink Choices
Tea: Black and green teas provide safe doses of caffeine along with some health benefits from the antioxidants flavonoids they contain. Although caffeine contents vary, the average cup of black tea provides about 40 milligrams (compared to 100 to 120 milligrams in a cup of coffee).
While coffee doesn't cause acne, some studies suggest it can make it worse. Caffeine makes you feel alert and awake but also leads to a heightened stress response in the body. Stress hormones, such as cortisol, may increase the amount of oil produced by your sebaceous glands, meaning you can be more prone to breakouts.
Adolescents and young adults need to be cautioned about excessive caffeine intake and mixing caffeine with alcohol and other drugs. Women who are pregnant or who are trying to become pregnant and those who are breast-feeding should talk with their doctors about limiting caffeine use to less than 200 mg daily.
For this reason, it might feel natural to reach for anything caffeine when your brain feels foggy. Yes, it may be beneficial for a quick mental boost but ultimately, caffeine does not address the root cause of your brain fog.
Wenk, Ph. D., coffee does not raise IQ levels. The caffeine in coffee only increases the brain's processing speed but it doesn't lead to significant long-term changes in cognitive performance.
What's the better choice, coffee or tea? “Neither is particularly harmful, and both offer an abundance of potential health benefits. Like most things in life, it comes down to portion control and individual preference,” Bollig said. If you aren't sensitive to caffeine, both are considered healthy.
Long-term effects at this level may include chronic insomnia, constant anxiety, depression, and stomach problems. It can also cause high blood pressure or make high blood pressure worse. More than 300 mg of caffeine (about 2 to 3 cups of coffee) in a day may be linked to miscarriages and low-birth weight babies.
The level of caffeine in your blood peaks about one hour later and stays at this level for several hours for most people. Six hours after caffeine is consumed, half of it is still in your body. It can take up to 10 hours to completely clear caffeine from your bloodstream.
With so many different jobs, it's clearly important to keep the liver healthy. And studies show coffee may protect against liver disease. Most of the benefits are thanks to antioxidants. A large 2021 study found that drinking coffee was associated with a lower risk of liver disease.
For healthy adults, the FDA has cited 400 milligrams a day—that's about four or five cups of coffee—as an amount not generally associated with dangerous, negative effects.
When blood concentrations peak, you are likely to feel the characteristic effect of caffeine: a boost in energy. The reason for this phenomenon is that caffeine blocks specific receptors in the brain that mediate critical functions like sleep, arousal, cognition, memory, and learning.
By quitting, you can return to a normal state of alertness and improve energy levels. Financial Savings: Modern specialty coffee drinks can take a big bite out of your monthly budget. Lower Blood Pressure: Quitting caffeine can lower your blood pressure and take pressure off of your heart.