Ingredients
What Is Green Tea Extract?
Green tea extract is a concentrated preparation of compounds from green tea leaves (*Camellia sinensis*), typically including catechins such as EGCG and, in mos
Read GuideUnderstand Your Everyday Energy Choices
Coffee, tea, energy products and supplements can contain very different amounts and sources of caffeine. Learn how to compare labels, understand serving sizes and make better-informed choices for your routine.
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Ingredients
What Is Guarana?
Guarana is a climbing plant native to the Amazon basin whose seeds contain naturally occurring caffeine - typically at a higher concentration than coffee beans.
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How to Read an Energy Supplement Label
Work through an energy supplement label in order: caffeine per serving, servings per container, serving size, stimulant ingredients (including caffeine-containi
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Caffeine
Hidden Sources of Caffeine
Beyond coffee, caffeine hides in black and green tea, chocolate, guarana, yerba mate, green tea extracts in supplements, some soft drinks, and certain medicatio
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Caffeine
When Should You Stop Drinking Caffeine Before Bed?
Research generally suggests avoiding caffeine in the hours before bedtime, with many studies and sleep organizations pointing to the afternoon-to-early-evening
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Caffeine
How Long Does Caffeine Stay in Your System?
Caffeine's average half-life in healthy adults is about 5 hours, meaning roughly half the caffeine from a cup of coffee is still in your system five hours later
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Caffeine
Coffee vs. Energy Supplements: How to Compare Caffeine
Compare caffeine sources by seven factors: caffeine per serving, serving size, servings per container, ingredient sources of caffeine, additional ingredients, s
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Caffeine
What Does 50-60 mg of Caffeine Mean?
Fifty to sixty milligrams of caffeine is roughly half the amount in an 8-ounce cup of brewed coffee, and a bit more than a cup of black tea. It is a moderate am
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How Much Caffeine Is in Coffee, Tea and Common Energy Products?
An 8-ounce cup of brewed coffee contains roughly 80-100 mg of caffeine. Black tea has about 47 mg per 8 oz, green tea about 28 mg, a 1-oz espresso shot about 63
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