With over one billion people worldwide drinking coffee daily, it’s fair to say many of us are regular caffeine consumers. It’s one of the most common dietary ingredients in the world, found in energy drinks, tea, and even chocolate.

Dr Brian Fisher, clinical director at wellness app Evergreen Life, has shared his knowledge on the stimulant to help educate readers on the effects of caffeine.

“Occurring naturally in over 60 plants, caffeine is a natural substance which stimulates the brain and central nervous system, leading to the feeling of alertness. Man-made, synthetic caffeine also exists, added to many foods, drinks and medicines.”

“ Caffeine is absorbed into the body within around 45 minutes once consumed, remaining in the blood for anywhere between 1.5 and 9.5 hours after being broken down in the liver. Affecting the brain the most, caffeine helps to prevent tiredness and increase awareness as it blocks the effects of adenosine, the chemical responsible for making you feel fatigued.”

“There’s a great many foods and drinks that contain caffeine, from the usual suspects such as tea and coffee, containing around 47mg and 90mg of the stuff respectively, to some options you may not consider, such as an ounce of dark chocolate containing around 24mg. A standard can of cola contains roughly 40mg of caffeine on the fizzy drink front, while energy drinks usually contain 85mg. Even decaf coffee isn’t caffeine-free, containing about 4mg per cup.”

“So, other than keeping you awake, what are some of the benefits of caffeine intake? Researchers have found that caffeine can act as an antidepressant, with an 8% reduction in the risk of depression from daily intake.”

“It has also been found to help with exercise, including improvements in muscle endurance, sprinting and jumping. Caffeine can also reduce the risk of type 2 diabetes and obesity.”

“And the risks? While the scientific community at large says that caffeine has no adverse effects if consumed in moderation, there are still outliers to this fact. For example, some individuals may be genetically more sensitive to caffeine than others, and tremors, difficulty sleeping, and an irregular heartbeat have all been linked to excessive caffeine intake.”

“It can also cause a short but dramatic spike in your blood pressure, so those who already suffer from high blood pressure should consult their doctor about a healthy intake. For adults who aren’t pregnant and have no pre-existing health conditions, 400mg a day, or around four–five cups of coffee a day, isn’t associated with any dangerous side effects.”