Coffee may protect your heart, but energy drinks could harm it
A new American Heart Association scientific statement concludes that moderate coffee consumption (up to 400 mg caffeine daily) is safe and may lower cardiovascular risk, while high doses in energy drinks pose heart dangers.
The American Heart Association (AHA) has released a new scientific statement on caffeine and cardiovascular health, reviewing the latest evidence. Caffeine is the world's most widely used stimulant. The AHA states that for most adults, up to 400 mg of caffeine per day – equivalent to about 3 to 5 cups of plain black coffee – is safe and does not increase cardiovascular risk.
Research suggests that black caffeinated coffee (without added sugars, syrups, or cream) may be associated with lower risks of type 2 diabetes, coronary heart disease, stroke, heart failure, and some arrhythmias. However, the evidence is largely observational, meaning it cannot prove cause and effect. Coffee contains many bioactive compounds with antioxidant and anti-inflammatory properties that may contribute to benefits.
The statement cautions that high caffeine doses, especially from energy drinks and energy shots, can be harmful. These products contain 40–69 mg of caffeine per fluid ounce – 3 to 4 times more than regular coffee. Such concentrations have been linked to elevated blood pressure and abnormal heart rhythms, even in healthy adults under 30. Additionally, energy drinks often contain other ingredients that accelerate caffeine absorption, potentially increasing risks.
Individual responses to caffeine vary widely due to genetics, metabolism, age, and habitual use. People with high blood pressure may be more sensitive. The statement also notes that unfiltered coffee (espresso, French press, Turkish coffee) contains cafestol, which can raise LDL (“bad”) cholesterol, while paper-filtered and instant coffee do not.
The AHA writing group, led by Dr. Gregory M. Marcus, calls for more randomized controlled trials to clarify effects of different caffeine sources. Due to insufficient rigorous evidence, caffeine was not included in the AHA's 2026 Dietary Guidance to Improve Cardiovascular Health. The key takeaway: pay attention to your body's response and consult your healthcare team for personalized advice.
