Caffeine is the most widely consumed psychoactive drugs in the world. It owes all this to its properties. In particular, its stimulating properties. But are these the only properties it possesses? Can it do any harm? And can everyone consume it? You will find out in this blog!

Caffeine – what exactly is it?

Caffeine is actually 1,3,7-trimethylxanthine. It sounds complex! But it’s actually a white powder that tastes quite bitter. The interesting thing is that caffeine, once it enters our body, is quickly absorbed. It is also worth mentioning here that caffeine crosses the blood-brain barrier. The metabolism of this compound takes place in the liver, and is excreted in small quantities in the urine.


Benefits of caffeine for the human body

  • May lower risk of developing certain types of cancer
  • Reduced risk of neurodegenerative diseases (Parkinson’s disease, Alzheimer’s disease)
  • Has the ability to improve exercise performance
  • Improvement in cognitive function
  • Protection against cell damage as it contributes to the reduction of oxidative stress markers

Does coffee contain the most caffeine? 

Although caffeine is one of the main ingredients in coffee, coffee does not contain the most caffeine. There are products with a much higher caffeine content. One example is guarana. According to research, guarana seed extract contains around 4-6 % caffeine, which is more than coffee beans. Another example of a caffeine-containing product is ginseng. The stimulant is found in teas, in particular Yerba mate once in green tea.


Can it be dangerous?

Like any substance, in excessive amounts it can have a toxic effect. The daily maximum dose for an adult without health contraindications is 400 mg/day (equivalent to 4 cups of brewed coffee per day). If the recommended dose is exceeded, an overdose occurs. Then the following symptoms occur in the body:

  • Anxiety and muscle tremor
  • Headache
  • Nervousness and problems with concentration
  • Gastrointestinal problems
  • Increased urination
  • Tachycardia
  • Arrhythmia
  • Psychomotor agitation
  • In extreme cases, caffeine overdose can be fatal

Can everyone consume caffeine? 

There are a number of conditions that prevent the consumption of this compound. These include peptic ulcer disease or gastroesophageal reflux disease, as it can exacerbate discomfort. Those with kidney disease or liver disorders need to be more mindful of their caffeine consumption. Pregnant women should take special care and, above all, consult their doctor for specific guidance. Studies show that if a woman tolerates pregnancy complaints well, she can consume caffeine, but it is very important that the daily maximum concentration is lower than for other adults – it should not exceed 300 mg/day. If you are concern about your caffeine intake, you can also consume caffeine free teas and coffee. 


Caffeine is a valuable compound that causes many benefits for our body. However, it is important to keep in mind the recommended daily intake, which should not be exceeded. If you are taking medication or are pregnant, please consult your dietitian before you start taking caffeine products.

To book a 1-1 consultation with one of our dietitian specialist, click HERE

By Martyna Slotwinska, dietitian intern, revised by Reema Patel, Registered Dietitian at Dietitian Fit & Co.


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