0006 - Is coffee good for you?
Coffee is the most commonly consumed psychoactive substance in the world, but it often gets bad press. However, if you drink it in moderation and at the right time, coffee can have powerful health benefits. So, if you are addicted to your first (and second?) morning cup of coffee, all is not lost!
- The health benefits
Coffee is the biggest source of antioxidants in the Western diet, outranking fruits and vegetables. This might be one of the reasons for the multiple health benefits identified by most studies:
it gives a short term boost in brain function, alertness, energy and performance
it fights the damaging effects of free radicals that contribute to ageing and diseases
it reduces the risk of developing type 2 diabetes, heart diseases, strokes, certain cancers, Parkinson's, Alzheimer's, liver cirrhosis, depression and of being suicidal.
it slows down the rate of cognitive decline and promotes neuronal survival and growth
it can promote weight loss by increasing the body metabolic rate.
Some studies even show that coffee drinkers live longer! That said, these studies generally show a correlation between coffee consumption and diseases outcome, which does not mean causation.
- The dark side of coffee
Coffee can also have a number of negative side effects.
Too much caffeine can cause jitteriness, anxiety, nervousness, heart palpitations, increased breathing rate and blood pressure, panic attacks but also difficulty to fall asleep, insomnia, upset stomach, nausea, vomiting...
When you consume less coffee than you usually do, you can develop withdrawal symptoms such as fatigue, brain fog, irritability and headaches.
So, if you are sensitive to caffeine, feel stressed or anxious, or have health issues associated with these side effects, reduce your intake or avoid it altogether.
- How caffeine works - Did you know this?
Adenosine is a neurotransmitter that makes you feel tired and sleepy. It builds up during the day, peaks before bed-time and is cleared out at night. Caffeine binds to adenosine receptors and blocks the adenosine from getting in. It disables adenosine sleep-inducing effects and fools your body into thinking it is awake and energised. 12 to 18 hours after your last cup of coffee, all the caffeine has been metabolised. This allows the adenosine to kick in, which makes you feel tired, sleepy and can trigger headaches.
When you have multiple cups of coffee daily, you develop a tolerance to caffeine: you need more to get the same energy boost. The brain thinks there is an adenosine shortage and makes more adenosine receptors. When the caffeine wears off, more adenosine can get in, which lowers your baseline energy, mood and performance. You wake up groggy and think that coffee switches your brain on, but the energising effect you feel is actually just your energy levels going back to what used to be your normal.
To reduce or avoid the dependence, you need to cycle off of caffeine, for instance at the week-end or on vacation. You can also swap to tea, decaf or chicory every other day.
- How many cups can you have?
The general advice is to have less than 400 mg of caffeine a day, which is about 2 to 5 cups of brewed coffee or 5 to 10 shots of espresso. The ranges are quite large as the caffeine contents can vary a lot: 70 to 165 mg per cup of brewed coffee and 40 to 64 mg per shot of espresso.
A medium or large take-away coffee can be more than one cup (8 oz): it can be 2, 3 or more cups depending on how strong the roast is. One single Starbucks Grande packs 330 mg of caffeine!
And you need to count as well the caffeine you get from other sources such as colas, energy drinks, teas (25 to 50 mg per 8 oz cup), chocolate/cocoa and supplements.
- When should you drink coffee?
Avoid coffee after lunch. Caffeine has a half-life of around 5 to 7 hours: if you have a coffee a 2 pm, half of the caffeine remains in your system around 7 to 9 pm. Your genes determine whether you are a fast or a slow coffee metaboliser. This is why some people can drink coffee in the afternoon and still sleep at night (lucky them!).
Avoid coffee first thing in the morning. I know this is going to be a tough one for many of you. Let me explain. We have a circadian rhythm that regulates our sleep-wake cycle and other physiological processes. Early morning, our cortisol goes up to wake us up and give us the energy to start our day. Cortisol levels peak about 30 to 45 minutes after awakening and remain high for a couple of hours. If you start your day with a coffee, it interferes with your body's natural awakening process. This is why it is better if you can wait a bit before drinking your first cup. Try starting with a decaf instead.
- What else?
Use your own stainless steel or ceramic cup when you buy take-away coffee. It is better for the environment and for you as well. The plastic lid on the coffee cup leaks harmful chemicals back into your coffee, due to the steam.
Avoid loading your coffee with milk, sugar or artificial sweeteners: they add "empty" calories and bring other potential health issues.
Buy organic coffee or decaf. Conventional coffee beans are loaded with pesticides and herbicides.
Buy decaf that has be decaffeinated using the Swiss Water process that does not use chemical solvents. Decaf doesn't have the stimulant benefits of regular coffee but it still contains similar amounts of antioxidants. So it is a great alternative if you want to reduce your caffeine intake.
Overall, the consumption of coffee has more positives than negatives. So go ahead and enjoy your morning cup(s)!
See references here.