Tea is an ancient drink that is made by steeping the leaves of the Camellia sinensis plant in boiling water. The resulting drink contains active ingredients such as caffeine, flavonoids and fluoride. Many health benefits have been linked to regular tea consumption, including one observational study that noted an 11 percent decrease in heart attack risk for subjects drinking three or more cups of tea per day. However, excessive consumption can lead to some adverse side effects.

If you rely on caffeine to wake you up and keep you going, you aren’t alone. Caffeine is used daily by millions of people to increase wakefulness, alleviate fatigue, and improve concentration and focus.

Why is caffeine so addictive?

Dr Chidi explains: “Caffeine – along with other drugs such as cocaine and nicotine – is particularly addictive because it goes straight to the brain.”It triggers a fast release of the stimulant adrenalin, which makes you feel more alert and is why we crave coffee so much in the morning.But while your first tea or coffee may perk you up, studies show beyond this first high you don’t get much more of a kick from further cups.More disappointingly, that first cup probably doesn’t even boost your work performance. During one study, the typing levels of two groups of secretaries were monitored – one group who had no coffee, the other up to five cups.While the coffee drinkers typed faster, they made 10 times as many mistakes.Furthermore, when a caffeine buzz wears off, you end up feeling twice as tired as you were before.Dr Chidi says: “This is because brain chemistry doesn’t like being interfered with by taking stimulants, so it releases chemicals that dampen the alert response. This lowers energy levels and mood, so you feel like another coffee – which continues the cycle.”

There are some adverse side effects when too much caffeine is consumed.

Rapid Heart Rate

Because having caffeine excites your nervous system, it can put more pressure on your heart to keep up with this stimulated body state. As this happens, your heart rate may speed up to accommodate the extra work your body is doing. Having a rapid heart rate can be dangerous, especially for those who have a heart condition or suffer from irregular heart rhythms.

Difficulty Sleeping

Caffeine helps to keep you awake and alert, so it’s no surprise that having too much of it could interfere with your sleep patterns. It’s best not to have caffeine shortly before going to bed since this could keep you awake even longer. Even if you haven’t had caffeine recently, having a lot over the course of the day can still affect your ability to fall asleep at night. For some people, this produces a cycle where they don’t get enough rest at night, causing them to rely more on caffeine during the day.

Frequent Urination

Caffeine is a diuretic, which means that it helps your body get rid of fluids. This can lead to increased frequency of urination, especially when for individuals who get their caffeine fix through a drink like coffee, soda or tea.


The diuretic effects of caffeine may lead to nausea in some people as well. In some cases, people may even vomit after having too much caffeine, although people are more than likely to just feel nauseous, and actually vomiting is a very rare side effect.


People who drink too much caffeine may find that they experience headaches due to the stimulant’s effects on the brain. The pain may have varying levels of intensity and can be easily confused with other medical problems.


Some people do not deal well with the increased stimulation in their brain and nervous system, which can be the result of drinking caffeine. This could potentially lead to anxiety caused by the inability to deal with caffeine’s effects on the body. In more severe cases, some people even experience symptoms of depression from having too much caffeine.

Muscle Tremors

Many people experience some kind of body tremor or jitteriness after drinking too much coffee, which is a side effect of the overstimulation of the nervous system. Someone who stops consuming caffeine after having a long-term dependency on it might even suffer from withdrawals.

Decreased Bone Mass Density

Over time, consuming large amounts of caffeine may decrease a person’s bone mass density. It is believed the cause of this is the way in which caffeine interferes with the body’s ability to absorb calcium. In severe cases, a person with significantly decreased bone mass density could even develop osteoporosis.

Breast Lumps

People who drink too much caffeine could find that they are developing one or more painful lumps in their breasts, which is also known as fibrocystic disease. In some cases, simply cutting back on your caffeine intake will cause these lumps to disappear.


Children who have too much caffeine may not be getting adequate nutrition for proper growth and development. This is particularly true when a child has caffeinated drinks instead of healthy drinks like water, milk or juice. Additionally, caffeine could decrease the child’s appetite, which would increase the likelihood that they are not getting adequate nutrition in their diet.

Are YOU having too much?

It’s recommended you don’t exceed 400mg of caffeine per day (200mg if pregnant) – but how much do your favourites below contain?

  • A large Americano – 300mg
  • A cup of home-made filtered coffee – 150mg
  • A takeaway latte – 150mg
  • Mug of instant – 100mg
  • 2 x Anadin Extra painkillers – 90mg
  • Can of Red Bull (250ml) – 80mg
  • Cup of tea – 75mg
  • An espresso – 70 mg
  • Bar of plain chocolate (50g) – 50mg
  • Can of Diet Coke – 42mg
  • Cup of green tea – 40mg

Tips on quitting

  • Choose green tea over ordinary tea or coffee. It has a fraction of the caffeine, is packed with antioxidants and fills the “hot drink” void.
  • Cut down on sugar. Reaching for coffee is usually because of an energy crash that is caused by eating sugary foods.
  • Sprinkle cinnamon on to food. It helps avoid energy crashes by regulating blood sugar.
  • Try a natural light alarm clock to help you wake up more gently – you’ll feel more alert in the mornings and less dependent on caffeine.