Have you ever wondered if the coffee you drink is helping or harming you?
Before we begin to answer the question, here’re a few coffee facts:
- Coffee is one of the most frequently consumed psychostimulants in the world
- It’s the most popular beverage following water
- The International Coffee Organisation reported that between 2018 and 2019, 129.43 million bags were exported worldwide (1)
Coffee is an enormous industry and yet the research on the effect it has to our health is a minefield of information. It’s not hard to find conflicting science on the long term health implications. One source will state that coffee can contribute towards disease whilst another will sing its praises for longevity. This is very confusing when trying to get clear answers as to whether coffee is harmless or making us sick.
The average adult consumes approximately 1-2 cups per day. Whether you drink more or less than that amount is unique to each individual but from a health perspective it seems that drinking 400mg or less of caffeine should be on the safe side for healthy adults (2). This equals about 4 cups.
No matter the conflicting information, we all innately have an idea of our caffeine limits and know when we’ve overstepped the mark! So given the research inconsistencies, you should listen to your instinct as to whether you should be drinking coffee and how much is right for you. You know if caffeine is not your friend because you can feel it! Here’re some signs that you should probably step away from the cafetiere:
- Anxiety
- Nervousness
- Energy crashes
- Negative feelings
- Bloating
- Feeling jittery
- Inability to concentrate
Below are reasons coffee could be a friend or indeed a foe:
Friend
- Coffee stimulates the release of the warm and fuzzy neurotransmitters serotonin and dopamine. Let’s be honest, when these guys kick in you’re pretty much ready for anything! This can make your day all the more enjoyable and increase productivity.
- A coffee in hand is a brilliant way to bring people together by helping you to perk up and feel ready to socialise. It’s also a great topic of conversation to connect over, as seen as 80% of us drink it!
- The caffeine in coffee stimulates your skeletal muscles to contract at lower thresholds. This can manifest as increased tension in your muscles at rest. If you take that to the gym you’ll find that you’ll train harder and fatigue less than usual (3), especially when paired with adrenaline which is also stimulated by caffeine (4). This results in a better workout leading to long term increased levels of fitness.
- Coffee stimulates the bowels to release its contents meaning bye bye constipation!
Foe
Coffee acts as a fight or flight stimulant placing you in an unwanted state of stress. It’ll prepare you to be alert and ready for anything, even if it’s just your laptop! It does this by stimulating the release of adrenaline and cortisol (5) which have the following effects:
- Increased heart rate and size of blood vessels
- Increased focus on what’s in front of you
- Increased blood flow to the skeletal muscles in your arms and legs which can cause shakiness
- Release of stored glucose into the blood stream ready for energy expending activities
- Temporary Increased insulin resistance in the cells so the glucose can stay in your bloodstream for longer
For the reasons stated above, women need to be extra careful when drinking caffeine especially in excess amounts. Women have a more complicated and delicate hormonal system than men and stress can cause havoc with the balance possibly leading to menstrual cycle complications (6). Although the association between hormone issues and caffeine hasn’t been agreed upon in the studies I’ve seen so far, it’s a known fact that prolonged stress can unsettle female function. Therefore if you already deal with irregular periods, anovulatory periods or any menstrual/reproductive issues in general, re-evaluate your coffee consumption and at least reduce your intake.
- As a stimulant, coffee keeps you awake and alert. Handy if you need to stay up late or require an extra perk in your day. But, if you experience sleep difficulties you might want to consider reducing or cutting coffee out altogether until your sleeping habits return to normal. Caffeine can be circulating in your system from 2-12 hours (4) depending on your unique chemistry, whether you’ve eaten or even if you’re a smoker or pregnant (smokers metabolise caffeine quicker, pregnant women metabolise slower (7)). It’s also based on your genes. The CYP1A2 gene decides how fast the coffee is processed and absorbed into your system (7), and we all have unique expressions of this gene. Therefore, keep this in mind and ensure you don’t consume coffee even after midday if you have sleep challenges.
- It’s addictive. Have you ever tried to come off coffee? Did you get any side effects? Worryingly headaches, tummy aches and energy crashes are popular responses to caffeine withdrawal. It’s fine if you don’t need to abstain in the first place, but what if you fall pregnant, or if you forget your Aeropress on a camping trip? The good news is that the symptoms will usually reside after a few days….. but ouff!
Friend or foe? You decide!
References
1. International Coffee Organisation. (2019). ‘Trade statistics – September 2019’. Available at: http://www.ico.org/show_news.asp?id=705 (Accessed: August 5th 2020).
2. Gaspar, A. et al. (2016). ‘Personal characteristics of coffee consumers and non-consumers, reasons and preferences for foods eaten with coffee among adults from Federal District, Brazil’, food Sci. Technol, Campinas, 36(3), pp.432-438.
3. Richardson, D. L. Clarke, N.D. (2016). ‘Effect of coffee and caffeine ingestion on resistance exercise performance’, Journal of Strength and Conditioning Research, 30(10), pp.2892-2900.
4. Cappelletti, S. et al. (2015). ‘Caffeine: cognitive and physical performance enhancer or psychoactive drug?’, Current Neuropharmacology, 13(1), pp.71-88.
5. Lovallo, W.R. (2005). ‘Caffeine stimulation of cortisol secretion across the waking hours in relation to caffeine intake levels’, Psychosom Med, 67(5), pp.734-739.
6. Nagma, S. et al. (2015). ‘To evaluate the effect of perceived stress on menstrual function’, Journal of Clinical and Diagnostic Research, 9(3).
7. Thorn, C.F. et al. (2012). ‘PharmGKB summary: caffeine pathway’, Pharmacogenet Genomics, 22(5), pp.389-395.
