Ah, coffee, the savior that allows you to survive another long day in the open-plan office and not nod off between meetings... You think you can't live without your shot of espresso, but you're still wondering at what dose caffeine can go from ally to sworn enemy?
Because yes, from a certain quantity, caffeine can harm your sleep or your state of health.
So, how much caffeine should you not exceed? And how many coffees (or Red Bulls, if you like your caffeine with bubbles) does that translate to? We'll tell you everything!
The effects of caffeine on your body: lots of benefits, but be careful of excess
Before warning you about the possible effects of too much caffeine, we wanted to clarify things! Because yes, coffee does have beneficial effects :
- 🔋 Stimulating effect: this is the main reason why we drink coffee, for its famous boost!
- 🤓 Boost concentration and cognitive performance, release of endorphins.
- ✅ Antioxidant effect: Coffee contains antioxidants, molecules that protect our cells against damage caused by free radicals, thus helping to prevent cellular aging and certain diseases (such as type 2 diabetes or cardiovascular diseases).
💡 Please note: this information should still be taken with a grain of salt, but some recent studies suggest that regular and reasonable consumption of coffee could have a beneficial impact on life expectancy (Impact of coffee intake on human aging: Epidemiology and cellular mechanisms - Cátia R. Lopes, Rodrigo A. Cunha)
Well, we're not going to recommend that you give yourself an intravenous drip of Robusta: like any food or drink, coffee consumption is beneficial in controlled doses.
Because if you consume too much, caffeine can quickly turn against you. According to the EFSA (European Food Safety Authority), the side effects of excessive caffeine consumption can include:
- 😴 Sleep disturbances: Caffeine is a stimulant that binds to adenosine receptors, a neurotransmitter that promotes sleep. While it's great for fighting fatigue at the start of the day, it can quickly lead to sleep disturbances! These include increased time to fall asleep, poor sleep quality, poor sleep cycle timing, and more frequent nighttime awakenings.
- 😫 Increased anxiety: Adenosine is also known for its relaxing effects on the central nervous system. In its place, caffeine can also cause hypervigilance, nervousness, irritability, and anxiety.
- 📈 An increase in blood pressure: Caffeine has a vasoconstrictor effect . When you drink too much coffee, it can temporarily increase blood pressure, especially in people prone to hypertension. For some at-risk individuals, coffee and eye pressure do not mix well. Rest assured, if you have no history or risk factors, moderate consumption is not dangerous for your blood pressure.
- 🤢 Gastrointestinal disturbances: If you have a sensitive digestive system, too much coffee can upset your stomach.
- 🫀 Heart palpitations: People sensitive to caffeine or with certain heart conditions are advised to moderate their coffee consumption. Indeed, tachycardia (increased heart rate) can be observed with excessive caffeine intake.
And of course, while coffee and tea have positive health effects, this is NEVER the case with energy drinks: there's nothing wrong with indulging in a soda every now and then, but don't expect any positive health effects.
Maximum dose: 400 mg (3 cups of coffee) per day
To avoid these side effects, EFSA recommends a maximum of 400 mg of caffeine per day for healthy adults.
To make it more explicit and easier for you to visualize, here is what it looks like in cups of coffee:
- 3 cups of 237 ml: or 3 mugs of long coffee
- 6 cups of 30 ml: or 6 espressos
💡 Note: Coffee isn't the only source of caffeine! If you're watching your intake, also be careful with guarana, tea, and energy drinks (like Red Bull, for example), or even chocolate. Some dietary supplements also contain it, so take the time to read the labels. As a guide, a 25cl can of Red Bull contains 80 mg of caffeine (and also 27 grams of sugar, or 7 sugar cubes).
A reduced dose for pregnant women and people at risk
For pregnant women, the recommended dose is 200 mg per day to avoid repercussions on the fetus and complications for the mother.
ANSES (French Agency for Food, Environmental and Occupational Health Safety) also recommends that breastfeeding women monitor their caffeine consumption: they are advised not to exceed 300 mg per day.
Finally, there are additional recommendations for certain populations:
- Children and adolescents: It is recommended not to exceed 3 mg per kg of body weight. This is a consideration for young people who may consume excess caffeine in cola or energy drinks. Risks: an impact on neurological development and sleep.
- Caffeine-sensitive individuals: Individual tolerance is an important factor to consider. If you are a caffeine-sensitive individual, the dose is lowered to 200 mg per day.
- In case of cardiovascular diseases: here too, it is recommended to limit to 200 milligrams per day to avoid adverse effects.
Pay attention to the quantity, but also to the timing!
The time of day you drink your famous black nectar is just as important as the quantity you drink throughout the day! We talk about this in more detail in our full article: When to drink coffee?
The basic rules:
- Wait an hour after waking up to drink your first coffee to give yourself time to wake up naturally.
- You can possibly have another helping in the morning.
- A cup of weak coffee in the early afternoon, but nothing after 4 p.m.!
- It's forbidden to serve yourself a coffee at the end of the day or evening, otherwise, you're guaranteed insomnia: caffeine remains active in your body for more than 6 hours, so opt for a caffeine-free infusion if you really want a hot drink.
- And so, in the evening, go easy on the vodka Red Bulls in the evening, eh :)
The final word: caffeine is no problem as long as you don't overdo it!
- Are coffee and tea dangerous for your health? Not in moderation. Consuming coffee in moderation can help you concentrate better and even prevent certain diseases thanks to the antioxidants these drinks contain. However, beware of sugary caffeinated drinks; consume them in moderation, as with all sodas.
- How much caffeine is safe to drink coffee? Up to 400 mg of caffeine per day for an adult. It's lowered to 200 mg for pregnant women and people sensitive to the effects of caffeine or at risk of cardiovascular disease. During breastfeeding, it's 300 mg. This amount varies depending on your caffeine tolerance, but also your age: we obviously advise children and teenagers not to drink coffee and limit the caffeine intake (colas and energy drinks) to 3 mg per kg of body weight per day.
- How many cups of coffee does that equal? 400 mg of caffeine is the equivalent of 3 mugs of long coffee or 6 cups of espresso.
- What are the health risks if I exceed the maximum recommended dose of coffee? Beyond this dose, you risk developing certain pathologies (high blood pressure in those already at risk, heart palpitations, digestive disorders), sleep disorders, and even anxiety. This is why the European Food Safety Authority recommends not consuming more than 400 mg of caffeine per day.
- Can I drink caffeine late in the day? We don't recommend it if you want to get a good night's sleep. Caffeine is fine until early afternoon. After that, it's best to switch to herbal teas!