Caffeine is a natural psychoactive substance widely used in foods and beverages across the world. It is found in many plants, including coffee beans, tea leaves, cacao pods, and kola nuts. Caffeine is synthetically produced and used in medications and energy drinks for its energizing and alertness-promoting effects.

Often consumed in drinks, and since there are so many variations in caffeinated products, it can be hard to know exactly how much caffeine is in a particular drink, especially a fresh-brewed cup of tea or coffee that has no label. Generally speaking though, coffee is the most potent and most consumed caffeinated beverage. A single eight ounce cup of coffee contains between 95-200mg of caffeine

When we consume caffeinated drinks and foods, our stomachs and small intestines quickly absorb the caffeine. The maximum effects of caffeine, usually occur between 30-60 minutes within consumption, although this timing can vary widely among individuals.

After being absorbed, caffeine is efficiently distributed throughout the whole body, and it crosses the blood-brain barrier.

Inside the brain, caffeine blocks adenosine receptors. Adenosine is a sleep promoting chemical that is produced in the brain during our waking hours. Normally, adenosine builds up in the brain the longer we’re awake. The more it builds up, the sleepier we become. When caffeine blocks this process, we remain alert and vigilant.

Caffeine can impact the onset of sleep and reduce sleep time,efficiency and satisfaction levels. Older adults may also be more susceptible to caffeine-induced sleep troubles. If you have difficulty sleeping, consider limiting any caffeine intake six hours before bed.

Caffeine can cause a burst of energy as it stimulates the central nervous system . Most people drink coffee in the morning to help them wake up, but caffeine consumed at night can cause more harm than good.

Since caffeine can be both beneficial and harmful depending on the dose, it is important to find a level of consumption that is healthy for you. The Food and Drug Administration (FDA) recommendation for safe daily caffeine consumption sits around 400mg, or 4-5 cups of coffee per day. A large cup of coffee can have up to 470 mg of caffeine content which is more than the daily recommended caffeine content.

The recommended cut-off time for caffeine use is a minimum of six hours before bedtime.


Monitoring your caffeine use is just one way you can help yourself get regular, restorative sleep. Other lifestyle choices, like a healthy diet and exercise regime, can contribute to healthy sleep. 


April 06, 2022

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