How Much Coffee is Too Much?

Who doesn’t love to start their day with a cup of coffee? It’s a drink for almost every occasion. First thing in the morning. Pour a cup. Are friends popping over? Get out the French Press. Going shopping in town or on your way to work? Grab a quick coffee. And, of course, there are those heavy-eyed Friday afternoons when a strong cup of coffee is the only thing powering you through to the weekend. 

Some days, though, it’s difficult to remember if you’re on your fourth or fifth cup. This raises the question: how much coffee is too much?


Are Eight Cups of Coffee Too Much?

Eight cups of coffee are an awful lot. But is it too much? Can you drink eight cups and still function? 

It’s a complex question.

Recent research from the University of South Australia analysed health records and dietary patterns of almost 350,000 people aged 37 to 73. The study found that drinking six or more cups of coffee per day can increase your heart disease risk by 22 per cent, compared to those who consume one or two cups daily. 

One potent little gene – CYP1A2 – increases the metabolism of caffeine. Researchers thought it might increase caffeine tolerance. Genetic differences didn’t affect the risk of heart disease, however.  

The study’s results were broadly attributed to excess caffeine consumption. If you’ve ever had one too many ristrettos, you’ll know the feeling. Jitters. Anxiousness. Fast heart rate. Mind racing. Nausea.

That’s because caffeine is a stimulant. 

The theory goes that by consuming too much caffeine, your blood pressure rockets. Like high-pressure water pipes, the force of the blood is enough to damage the surrounding vessels. The result: cardiovascular disease. 


Is 1000 mg of Caffeine Too Much?

First, how much is 1000 mg?

In your average cup of coffee, expect around 95 mg. That means 1000 mg is roughly ten cups. In a Presto bag of beans – take our House Espresso 1KG bag containing about 120 cups – expect between 70 to 140 mg of caffeine per cup. That’s the average for brewed coffee. Whereas instant, like our new Columbian Instant Coffee, packs a more moderate 30 to 90 mg. Surprisingly, decaf coffee still includes a drop of caffeine – around 0 – 7 mg per cup.

Yes – 1000 mg is a lot of caffeine. Likely to cause significant health effects.

Published in Food and Chemical Toxicology: a 2017 review discovered up to 400 mg a day of caffeine – around four regular cups – did not cause any significant health risks in adults. 

It’s not all bad news, however. 

The South Australian study also found that compared to one or two cups per day, participants who didn’t drink coffee or drank decaf had 11 per cent and 7 per cent higher heart disease rates, respectively. 

Coffee is rich in bioactive compounds like antioxidants and anti-inflammatories. When consumed little and often, it decreases the risk of heart disease, stroke, death, type 2 diabetes, liver cirrhosis, certain cancers, and even brain diseases like Parkinson’s or Alzheimer’s. 

So, don’t cut out coffee. Just consume in moderation. 


What Happens If You Drink Too Much Coffee in a Day? 

Ok, so keep your coffee intake to around one or two cups per day. Or, at worst, about 400 mg – four cups.

But what if you did keep drinking? What happens?

The side effects of coffee are widely known:

  • Headache
  • Nervousness
  • Insomnia
  • Irritability
  • Fast heartbeat
  • Muscle tremors

These are the results of caffeine’s stimulant effect. It’s kicking your body into overdrive. 

Most people will be able to tolerate different levels of caffeine. For some, one or two cups leaves them feeling jittery, while others happily sip back four freshly brewed mugs without so much as a tremor.  That’s not all genetics, though. If you’re a routine coffee drinker, you’ve likely built up some tolerance. Caffeine just doesn’t have the same effect it used to. Whereas, if you only have a cup once a month, you’re going to feel caffeine’s effects more potently. 


Caffeine and Sleep

If you’re struggling to get to sleep at night? If you’ve tried everything and it’s made no difference. Consider: caffeine may be your sleep troubles’ root cause. 

Caffeine works by blocking the receptor of the neurotransmitter adenosine. Throughout the day, adenosine builds up in your brain, generating what’s called sleep pressure. When the pressure reaches its zenith – and you can’t avoid bed any longer – you nod off. But, with caffeine blocking adenosine, your sleep pressure is falsely reduced, keeping you wide awake. 

Caffeine – even in small amounts – can linger in your bloodstream long after the last cup. By avoiding coffee in the afternoon and evening, you’ll go to bed feeling sleepy. No more lying-in bed: mind whirring. Just blissful sleep. 

Caffeine Consumption: Consider your medications

In your body, chemicals and nutrients interact with each other. Caffeine is no different. If you take the following medications or supplements, watch your caffeine intake:

  • Ephedrine: Used in decongestants. When coupled with caffeine, it increases your risk of high blood pressure, heart attack, stroke, and seizures.
  • Echinacea: A commonly used herbal supplement. It can increase caffeine’s blood concentration, enhancing the negative symptoms. 
  • Theophylline: Given to open up airways. It can potentiate and enhance caffeine symptoms like nausea and heart palpitations.


Coffee Consensus

If you’re drinking a couple of cups a day, there’s no need to worry. Up to four cups of coffee are known to have no negative effects. But, if you frequently lose track, or you’re brewing up your fifth or sixth cup in the afternoon, you’re drinking too much coffee.

At extremes, excess caffeine consumption can have serious long-term effects on your heart. Consume 12 cups or 1,200 mg of caffeine, and you’re heading towards dangerous territory. 

Stick to a few cups, however, and you’ll reap the remarkable health benefits of coffee. Oh… and did we mention it’s delightfully delicious.

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