Coffee is one of the world’s most popular beverages. It contains caffeine which is a psychoactive stimulant drug that speeds up the messages travelling between the brain and the body.
The psychoactive effects of caffeine influence neurotransmitters (mood hormones) such as dopamine and norepinephrine which leads to better mood, greater alertness, energy and improved cognitive function. Along with these positive psychoactive effects, coffee contains several minerals and antioxidants which provide a benefit to health. Research has shown that because of the caffeine, minerals and antioxidants found in coffee, regular or daily coffee consumption can help with:
- reducing the risk of cardiovascular diseases including heart attack, heart failure and stroke
- reducing the risk of developing type 2 diabetes
- reducing the risk of developing neurological diseases such as depression, Parkinson’s disease and Alzheimer’s disease
- improving physical performance
- promoting longevity or a longer life span.
Although there are many health benefits that come with regular or daily consumption of coffee, there are also many negative health effects for individuals due to the caffeine quantity.
On average, a cup of coffee contains anywhere between 60–350 mg of caffeine depending on your individual order. A standard Australian-made coffee contains approx. 100 mg of caffeine. If you order a large/double-shot coffee, that is approx. 200 mg of caffeine. If you have another large/double-shot coffee later in the day, that’s another 200 mg and so on. You can see how quickly and easily this could add up. Additionally, items such as energy drinks, tea (including green tea), soft drinks and even chocolate all contain caffeine which means your caffeine intake is not just limited to your coffee.
Here is how a high caffeine intake may be negatively affecting your health:
Stress and anxiety
Caffeine stimulates our adrenal glands to produce adrenaline and cortisol – our ‘stress hormones’. These are the hormones that activate our fight-or-flight response and amplify our reaction to stressful situations. As such, consuming coffee recreates a stress response but the body can’t tell the difference; it is just responding accordingly to the increased levels of adrenaline and cortisol in the system. This will lead to symptoms including shakiness, heart palpitations, racing heart and hyper-vigilance which leaves us feeling jittery, anxious and on edge.
Over time, continually elevated adrenaline and cortisol levels deplete the adrenal glands and they are no longer able to produce these hormones to keep up with demand, leading to a feeling of being ‘wired but tired’ and is the sign that the adrenal glands are fatigued. This has a flow on effect and begins to negatively affect other hormones.
Sleep quality and quantity
As mentioned earlier, caffeine is a psychoactive stimulant drug – it gives us that buzz and keeps us alert! Depending on how well our liver detoxification pathways are functioning, caffeine can remain in the system for up to 8–12 hours. If you are consuming caffeine in the afternoon, there is a strong chance that it will still be in your system in part when it comes time to go to bed, making it much harder to fall asleep. Caffeine also inhibits the uptake of the hormone adenosine in the brain which is required in high concentrations for sleep onset.
As a general rule, you should drink caffeinated beverages after 8 am, after you have eaten breakfast and no later than 11 am, especially if you are sensitive to caffeine.
Caffeine is very acidic which contributes to inflammation and is incredibly irritating to the gastrointestinal tract lining. Caffeine also increases gastrointestinal tract motility, causing a laxative effect, which is why bowel motions, looser stools or diarrhoea are commonly reported after caffeine consumption. The increase in gastrointestinal tract motility, or laxative effect of caffeine, negatively impacts the digestion process, resulting in improper digestion of food and nutrients. This influences the body’s nutrient levels, see below. Caffeine may also suppress appetite, as well as trigger bloating, heartburn and reflux.
Consuming caffeinated beverages with meals interferes with the metabolism and reduces the absorption of many important nutrients including magnesium, vitamin C, B vitamins, calcium and iron, each of which perform hundreds of different important functions in the body. Separate caffeinated beverages from your meals by 1–2 hours to assist your gut to metabolise, digest and absorb these important nutrients.
If you find you cannot get through the day without coffee, you are having issues with sleep onset at night-time or you are experiencing some of the above mentioned digestive issues, it might be time to start thinking about reducing your caffeine intake. It is worthwhile seeking the assistance of a naturopath to help restore your body’s own energy production and other system or organ functions that may have been impacted by excessive caffeine consumption over time.
Written by Perri Baldwin BHSc