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.
Caffeine increases heart rate and blood pressure, and too much of it can cause anxiety, insomnia, headaches, stomach irritation and an irregular heartbeat. It's also addictive. About 400 mg is the maximum amount of caffeine you should consume in one day, which equals about four cups of coffee.
The study, which was published in the European Journal of Preventive Cardiology, suggests that two to three cups of coffee a day may actually protect you from developing heart disease and even early death.
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. However, there is wide variation in both how sensitive people are to the effects of caffeine and how fast they metabolize it (break it down).
Up to 400 milligrams (mg) of caffeine a day appears to be safe for most healthy adults. That's roughly the amount of caffeine in four cups of brewed coffee, 10 cans of cola or two "energy shot" drinks. Keep in mind that the actual caffeine content in beverages varies widely, especially among energy drinks.
Some research suggests coffee can lower the risk for high blood pressure, also called hypertension, in people who don't already have it. But drinking too much coffee has been shown to raise blood pressure and lead to anxiety, heart palpitations and trouble sleeping.
Drinking 3 Cups of Coffee a Day May Help Maintain Low Blood Pressure, Study Says. Nick Blackmer is a librarian, fact-checker, and researcher with more than 20 years of experience in consumer-facing health and wellness content. Regular coffee drinkers also have lower blood pressure measurements, new research shows.
If you are wondering how much is too much, a review published in November 2017 in the journal Food and Chemical Toxicology found that intake levels of up to 400 mg a day, or about four 8-ounce cups of coffee, are not associated with health risks for adults.
In general, having two to three cups of coffee a day was associated with the greatest benefit, translating to a 10%-15% lower risk of developing coronary heart disease, heart failure, a heart rhythm problem, or dying for any reason.
Prior studies have also found moderate amounts of black coffee — between 3 and 5 cups daily — has been shown to lower the risk of heart disease, as well as Alzheimer's, Parkinson's, type 2 diabetes, liver disease and prostate cancer.
Lower Blood Pressure: Quitting caffeine can lower your blood pressure and take pressure off of your heart.
Diabetes: Caffeine might affect the way the body uses sugar. If you have diabetes, use caffeine with caution. Diarrhea: Caffeine, especially when taken in large amounts, might worsen diarrhea. Epilepsy: People with epilepsy should avoid using caffeine in high doses.
Research suggests that caffeine isn't a cause of abnormal heart rhythms or atrial fibrillation, and drinking four to five cups of tea or coffee a day shouldn't increase your risk of developing coronary heart disease either.
In this battle over health benefits, coffee comes out on top. Coffee drinkers can raise a mug to fiber, microbiome health and lowering risk for cancer and diabetes. But tea drinkers, do not despair. Tea is undoubtedly good for your blood pressure, cholesterol, stress levels, mental health and productivity.
The body adapts by creating more adenosine receptors, so people who drink coffee every day still sleep normally. As a result, your energy levels drop and you need coffee just to combat withdrawal symptoms. Those symptoms can include irritability, headaches, and exhaustion.
There can also be side effects to consuming too much caffeine, such as jitteriness, anxiety, nervousness, increased blood pressure, heart palpitations, difficulty sleeping, irritability, tension, and even exacerbated panic attacks.
Human response to coffee or caffeine can also vary substantially across individuals. 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.
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. It's even possible that people who drink coffee can reduce their risk of early death.
While coffee does not contain cholesterol, it can affect cholesterol levels. The diterpenes in coffee suppress the body's production of substances involved in cholesterol breakdown, causing cholesterol to increase. Specifically, coffee diterpenes may cause an increase in total cholesterol and LDL levels.
Recently, the American Heart Association (AHA) updated their guidance to indicate that people age 65 and older should ideally have a blood pressure reading lower than 130/80 mm Hg (millimeters of mercury). The first number (systolic) measures artery pressure when the heart is pumping.
However, caffeine can cause heart palpitations in people with caffeine sensitivity and those with an underlying heart condition. If you are new to consuming caffeine or are used to drinking excessive amounts, you are more likely to experience cardiac symptoms.