Demonised as the devil’s brew for many years, it seems coffee is making a comeback. The science is changing, and the media headlines are changing with it. For years, coffee only made the headlines for negative reasons but, in recent times, better quality studies have demonstrated interesting health benefits. So, is it time to rethink your relationship with coffee? Read on to hear our take on the most recent research available!
What’s in a coffee bean?
Well, firstly, it’s not a bean, it’s a seed. And, to understand the health benefits of it, we need to take a closer look at two key compounds – polyphenols and caffeine – found naturally in the coffee seed. Firstly, polyphenols. Many studies have found coffee polyphenols, such as chlorogenic acids, have amazing health-promoting attributes, including antioxidant, anti-inflammatory and anti-diabetic properties. And then there’s the caffeine. Caffeine acts as a stimulant to the nervous system and has been shown time and again to have a positive effect on brain function. So, promising stuff, isn’t it?
What does the research tell us about the health benefits of coffee drinking?
New research is coming out all the time. Here are some of the highlights of the recently published research.
- Regular coffee consumption significantly decreases our risk of type 2 diabetes. The relationship is dose dependent, with an intake of around 3-4 cups per day offering the most significant benefit. Both caffeinated and decaffeinated coffee offer benefits. Drinking 3-4 cups of tea also significantly lowers the risk of type 2 diabetes, though to a slightly lesser extent than coffee.
- Studies show coffee drinkers have a decreased risk of non-alcoholic fatty liver disease (NAFLD) a condition where there is excess fat in the liver of people who drink little or no alcohol. NAFLD is becoming a major public health issue as it is linked to an increased risk of diabetes, heart disease and stroke. Again, results suggest similar benefit for both caffeinated and decaffeinated coffee.
- There is a growing body of evidence to suggest moderate coffee drinking may reduce the risk of Parkinson’s disease and Alzheimer’s disease. This early research suggests results the benefits may be related specifically to caffeine. Further research is needed in this area.
- Caffeine has many positive effects on brain function, including increased alertness, concentration, mood and sense of well-being. It may improve exercise performance, while also raising metabolism and helping fat burning.
- Researchers have been looking at the relationship between coffee and cancer for decades and, while further studies are needed, research to date suggests that coffee drinking may lower the risk of certain types of cancer. Let’s look at that in a little more detail.
What exactly do we know about coffee drinking and reduced risk of cancer?
- The consumption of coffee, including decaffeinated, caffeinated, fresh and instant may reduce the risk of colon cancer.
- A high intake of caffeinated coffee (4 cups daily), may be associated with reduced cancer recurrence in patients with stage III colon cancer.
- Most research shows that coffee drinking does not raise your risk of breast cancer. For women who are post-menopausal, research has been even more promising, showing a possible link between coffee drinking and breast cancer risk reduction.
- Several studies have shown that coffee reduces the risk of breast cancer recurrence in women who have been diagnosed with breast cancer and treated with the drug, tamoxifen. This initial research suggests results are mainly due to the caffeine content of coffee, but also, in part to the polyphenol, caffeic acid.
- Coffee consumption has been associated with lower risk of liver cancer and oral/pharyngeal, prostate cancer, endometrial cancer and melanoma.
Is there any research which suggests coffee increases my risk of cancer?
Some studies suggest an increased risk of bladder cancer, specifically among males and non-smoking coffee drinkers but results are inconsistent and further well-designed large-scaled studies are warranted to provide more definitive conclusions. Most research articles suggest that coffee consumption is not associated with an overall cancer risk and in fact, for many cancers, the relationship appears to be inverse.
Can I drink coffee when I am having cancer treatment?
In general, there is no reason why you cannot drink coffee when you are undergoing treatment. However, pay attention to any treatment side effects – such as diarrhoea and insomnia – which coffee drinking may exacerbate. As always, listen to your body and do what feels right for you.
Are there any side effects of coffee drinking?
Yes! Caffeine tolerance varies greatly between individuals. While some people barely notice the effect of caffeine, others experience negative side effects, ranging from disturbed sleep and jitteriness, to anxiety and heart palpitations. Caffeine may also be highly addictive for some people, causing withdrawal symptoms like headaches and irritability when they try and reduce intake. If any of this sounds like you, then we recommend you avoid caffeinated coffee and try either decaffeinated coffee or green tea. While an 8oz freshly brewed coffee contains between 100-200mg caffeine, a green tea contains only 30-50mg caffeine and a decaffeinated coffee contains barely any, at 2-7mg.
I prefer to drink decaffeinated coffee. Is there anything I should know?
There are three methods for coffee decaffeination: The ‘swiss water’ and ‘supercritical carbon dioxide’ processes are considered chemical free while the ‘solvent’ process relies on synthetic chemicals. The level of solvent remaining after chemically decaffeinated the coffee bean is minimal, though, and below the level deemed safe by European regulations. However, if you wish to minimise your exposure, then choose coffee which is decaffeinated using one of the chemical free methods. The chemical free methods are also thought to produce a fuller flavour coffee than the chemically decaffeinated process.
Does decaffeinated coffee have the same health benefits as caffeinated?
Most research papers suggest decaffeinated coffee has a similar antioxidant content to caffeinated coffee and that decaffeinated coffee has similar health benefits to caffeinated coffee. Where the research has differentiated between caffeinated and decaffeinated coffee, we have discussed it above under specific health conditions.
I drink mostly instant coffee. Does this offer the same benefits as fresh coffee?
Most papers seem to suggest instant coffee contains similar amounts of antioxidants to fresh coffee. And in fact, we found one study which found instant coffee has higher levels of antioxidants than fresh coffee!
I’ve heard coffee is sprayed heavily with pesticides. What are your thoughts on this?
Coffee is indeed a heavily sprayed crop. From a health perspective, this does not appear to be an issue, since research shows that the processing and specifically the roasting of the coffee bean reduces levels of pesticides and fungicides by over 90%. There are, however, social and environmental issues associated with coffee growing, some of which would be alleviated by organic production methods.
Does coffee inhibit nutrient absorption?
Coffee drinking can reduce the efficiency of calcium absorption. However, research suggests there is no impact on bone health so long as calcium and vitamin D intakes are sufficient and coffee drinking is in moderation (up to 3 cups per day).
Coffee drinking can reduce the absorption of non-heme (vegetarian) iron. If you have low – or borderline – iron status, we recommend you drink coffee at least one hour away from both supplements and a meal.
Wow! That’s a lot to take in! Can you summarise for me?
Sure! Overall, research suggests that coffee drinking has a beneficial effect on health. Our aim is not to recommend whether you do or do not drink coffee, but to provide you with evidence-based information to make an informed decision. Coffee drinking has a range of negative side effects, and some people have a far greater tolerance to caffeine than others. We believe the level and type of coffee consumed should be set according to your own personal threshold. For example, if you experience negative effects drinking caffeinated coffee or you wake up in the morning feeling the need for coffee to function – we recommend you wean yourself off it. Simply do this by reducing your intake gradually. If, after a few weeks, you choose to re-introduce coffee, be attentive to how it makes you feel. And, here, we are talking in terms of anxiety, energy and digestion. If you decide caffeinated coffee isn’t right for you, good alternatives include de-caffeinated coffee and green tea. Of course, if you choose to drink neither coffee nor green tea, that’s OK, too! Yes, these maybe one source of antioxidants but our main source of antioxidants will always be vegetables and fruit, so you won’t be missing out!
Remember, we are all unique and while coffee will work for some of us, it won’t work for all of us. Always listen to your body and always do what feels right for you.
In line with the recent evidence about the benefits of coffee and to ensure we take a balanced approach to nutritional advice, we will be offering coffee to clients on courses from January with meals.