Caffeine is a stimulant and the most commonly used stimulant in the world. Commonly ingested in coffee, tea, some carbonated beverages and energy drinks. But besides these drinks, caffeine has shown to be increasingly prevalent in different foods covering multiple food groups. Every day, millions consume it to increase wakefulness, alleviate fatigue, and improve concentration and focus.

Amid myths and controversy about whether caffeine is good or bad for us, evidence suggests that moderate coffee consumption can bring both benefits and risks. 

Effect on your health

Starting with the good: caffeine can increase your short-term memory and alertness while also altering your overall mood. Caffeine is completely absorbed within the stomach and small intestine 45 minutes after ingestion, and its half-life in the body is approximately 3-4 hours.

The caffeine in one cup of coffee can stimulate the central system as it simultaneously lowers blood sugar, thus creating a temporary lift. Further research showed that “people who drink coffee regularly have up to 80% lower risks of developing Parkinson’s disease.”

On the contrary, caffeine does have a dark side. Caffeinated foods can contribute to a person’s struggle with either weight gain or hunger. The stimulant itself is known to increase appetite, to increase cortisol levels, and to increase levels of insulin. Any of these factors may combine with caffeine-induced stress that often affects the results of dieters, being that caffeine is a natural diuretic that can lead to water retention. Caffeinism, as it is often referred to, can come in waves of migraine headaches and sickness, which in turn can cause nervousness and a rapid heartbeat.

How to best use caffeine

How to best use caffeine — from a neuroscientist

Consume in small, frequent amounts.

Between 20-200 mg per hour may be an optimal dose for cognitive function.


Play to your cognitive strengths while wired.

Caffeine may increase the speed with which you work, may decrease attentional lapses, and may even benefit recall – but is less likely to benefit more complex cognitive functions, and may even hurt others. Plan accordingly (and preferably before consuming caffeine!)


Play to caffeine’s strengths.

Caffeine’s effects can be maximized or minimized depending on what else is in your system at the time. 


Know when to stop – and when to start again.

Although you may not grow strongly tolerant to caffeine, you can become dependent on it and suffer withdrawal symptoms. Balance these concerns with the cognitive and health benefits associated with caffeine consumption – and appropriately timed resumption. (For some, withdrawal from caffeine addiction can set in after 12-24 hours and last 2-9 days. Keep in mind that recall is best when the retrieval state matched the encoding state, i.e. if you were caffeinated when you learned it, be caffeinated when you’re trying to remember it.)



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