Too much caffeine? These are the warning signs coffee drinkers should know

Too much caffeine? These are the warning signs coffee drinkers should know

Over 1 billion people regularly drink coffee each day, but how much caffeine can the body actually tolerate, and how do you know if you've had too much coffee?

It begins with one coffee after you wake up, then a second as you get into work, a third after the midday slump, and then maybe one more in afternoon to get you through the rest of the day. Many coffee drinkers don't just drink one cup of coffee a day and have a daily caffeine intake of anywhere from 100mg to 400mg (and above). 

So what happens when you drink too much caffeine? These are the 7 signs and symptoms that you may experience if you have had too much coffee: 

  • Always thirsty - Coffee dehydrates our body, as a result we drink more water, which in turn leads to a constant urge to urinate. 
  • Poor and restless sleep - caffeine has a half life of 4-6 hours, so if you consume 100mg of caffeine around 4pm, the equivalent of a cup of coffee, you will still have 50mg of caffeine in your body at 8pm. If you have had multiple drinks throughout the day, this concentration will be higher, and you will have a hard trouble falling to sleep. 
  • Unsettled stomach -  many coffee drinkers associate a hot cup of coffee with a need to go to the toilet, and can become reliant on it for regular bowel movements. However, if you drink too much you could experience the laxative effects of coffee. 
  • Heart palpitations - caffeine makes you alert and promotes concentration, however if we overdo it, we can get palpitations as a result of an increase in blood pressure. 
  • Headaches - Smaller doses of caffeine can be beneficial for migraines however excessive caffeine can trigger unpleasant headaches. 
  • Increased blood sugar levels - A study by the Centre for Nutrition in the UK showed that if you drink too much coffee on an empty stomach, your blood sugar levels can increase by up to 50%. This can cause stomach pain, and also promote the development of diabetes in the longterm. 
  • Depression - Caffeine puts your body into an artificial stress situation, doing this everyday will put you body into a permanent state of alert. A consequence of this is exhaustion, anxiety, mood swings, insomnia, irritability, and even depression.


Coffee affects individuals differently based on factors such as genetics, age, pregnancy, smoking habits, and medications, influencing how quickly caffeine is absorbed by your body and how long it lasts. While there's nothing inherently wrong with daily coffee consumption, moderation is key, as excessive intake can lead to various symptoms indicating overconsumption. Recognizing these symptoms, such as restlessness or sleep disturbances, can signal the need to cut back on coffee or consider caffeine withdrawal, with decaffeinated coffee serving as a potential alternative for those sensitive to caffeine.