How Much Coffee Is Too Much?

A close-up view of four spoons with different coffee beans
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If you can’t start your morning without a jolt of caffeine, you’re not alone. More than 60 percent of Americans drink coffee every day, the National Coffee Association says.

That cup of java doesn’t just wake you up. Low to moderate doses of caffeine (40-300 mg) may improve reaction time, attention, alertness and vigilance, research shows. A study published in November 2021 linked regular coffee consumption with reduced cognitive decline and a possible reduction in the risk of developing Alzheimer’s disease.

How much coffee is recommended per day? An 8-ounce cup has about 80 to 100 mg of caffeine, and the FDA recommends no more than 400 mg a day. Too much caffeine could do more than make you jittery. High doses may negatively affect memory and attentiveness. It may also increase stress and anxiety levels, and a late-afternoon coffee could also affect sleep: Caffeine can stay in the body for up to seven hours.

To learn more about how coffee and brain health, read this article in Staying Sharp.

This content is provided for informational purposes only and is not intended to provide any expert, professional or specialty advice or recommendations. Readers are urged to consult with their medical providers for all questions.

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