Some food and beverage trends come and go, while others stick around for the long haul. Coffee is a drink that has been popular for decades, and continues to be a staple beverage for many around the world. In the United States and Canada, we consume a minimum of 2 cups daily. All told, the world drinks 2 billion cups total every single day. So is coffee and caffeine good or bad for you? Let’s delve into the pros and cons.
What Is Caffeine?
Caffeine is a compound found in certain plants. In nature, caffeine actually functions as an insecticide to protect the plant against critters who want to eat it. Caffeine is commonly associated with coffee beans and coffee, but you can also find it in:
- Tea (black and green which are both made from the tea plant camellia sinensis)
- Yerba mate (Ilex paraguariensis)
- Guarana (Paullinia cupana)
- Dark chocolate and cacao beans
- Kola nuts
- Energy drinks and sodas
The amount of caffeine in the coffee you drink depends on the type of beans, how they are roasted, how the cup of coffee is brewed and the serving size. An 8-ounce cup of coffee will have about 80-100mg, and the recommended safe amount according to government guidelines is about 400mg daily.
How Caffeine and Coffee Impacts Our Bodies
Coffee stimulates the central nervous system and has an almost immediate effect on our brain. We can clear coffee from our stomachs in about 20 minutes and then it enters the bloodstream, where it can impact various systems throughout the body. In our brain caffeine targets the receptors for adenosine, a compound that behaves as a neurotransmitter and helps us calm down and fall asleep. When adenosine is blocked by caffeine, however, we feel stimulated, awake, focused and alert. This is how coffee can help us wake up in the morning, or perk up whenever we feel we need it.
Caffeine quickly raises our blood pressure and heart rate; and it prompts our adrenal glands to produce a stress response and pump out cortisol and epinephrine. Coffee can often have an immediate effect on our bowels, too (many people use it as a laxative).
In the short-term, coffee consumption can make us feel alert and raring to go – but over time, especially when consumed as a stimulant, it can have negative impacts.
Health Effects of Caffeine and Coffee
The health benefits and drawbacks of coffee are hotly debated – and there are merits to both sides.
Negative Health Effects of Caffeine and Coffee
Insomnia and/or Sleep Disruption
As I mentioned above caffeine inhibits adenosine, which helps us to fall asleep. Being awake and alert first thing in the morning is beneficial; staring at your bedroom clock for hours trying to fall asleep is not. Coffee remains in our system for a long time, with a half-life of 3-5 hours. Studies on caffeine and sleep have found that coffee prevents us from falling asleep, reduces our amount of time spent sleeping, and compromises our sleep quality.
Caffeine stimulates the nervous system and induces a stress response, including an increased heart rate and blood pressure. For those who are sensitive to caffeine, or those who already struggle with anxiety, caffeine can make us feel nervous, anxious, irritable or even emulate a panic attack.
For children and young adults, who can be more sensitive to caffeine’s effects, both coffee and energy drinks can increase their risk of depression, anxiety, panic and nervousness.
Coffee and caffeine can prompt us to excrete important minerals for bone health like calcium and magnesium. In this study, greater coffee consumption was linked to lower bone density, and in this meta-analysis drinking coffee every day increased a woman’s risk of fractures (the risk of fractures was decreased in men).
Fertility and Pregnancy
High amounts of caffeine (over 200mg daily) may delay pregnancy, may increase the risk of pregnancy loss, and may lead to a lower birth weight in babies. In pregnant women, the half-life of caffeine in the body is longer because the liver enzymes that help to process it decrease. For nursing moms, caffeine may impact milk production and affect the sleep of their babies.
Coffee and caffeine stimulates our nervous system and gives us an almost-immediate boost of energy and focus. However, that energy boost can come down quite quickly, leaving us feeling sluggish and eager for our next coffee fix. Studies show that high caffeine intake is linked to feeling more tired in the mornings. Coffee addicts can find themselves in a pattern of highs and lows, and then when you factor in the sleep impairment coffee can cause we end up feeling more tired overall.
For some, caffeine can trigger heartburn. As coffee can stimulate the digestive tract, some may find it increases their transit time too much and they end up with diarrhea.
It’s A Diuretic
Coffee is a diuretic, meaning it can make us pee more. Though some studies conclude this excess urination doesn’t necessarily lead to dehydration, in my clinical experience those who drink a lot of caffeinated beverages aren’t consuming a lot of water or other hydrating foods (fruits, vegetables) and drinks.
The Good Stuff About Caffeine and Coffee
Coffee and caffeine isn’t all bad news – it has health benefits, and it can be a contradiction as some of its negative attributes can also provide positive advantages.
Improved Energy and Focus
Coffee is a brain stimulant – and it undoubtedly will make you feel more energized, focused and awake.
Lower Risk of Neurodegenerative Diseases
Evidence indicates that caffeine consumption can lower the risk of and improve symptoms of certain diseases like Parkinson’s and Alzheimer’s.
Studies on coffee and the heart show that coffee consumption is linked to a lower risk of cardiovascular diseases and death from cardiovascular events. Coffee is incredibly rich in antioxidants, which likely contribute to this protection.
Studies comparing high and low coffee consumption reveal that higher coffee consumption may reduce the risk of the following:
- skin cancer (both melanoma and non-melanoma
- prostate cancer
- endometrial cancer
- liver cancer
Type 2 Diabetes
Studies comparing coffee consumption between one to six cups daily found that drinking coffee decreased the risk of developing Type 2 diabetes. Surprisingly, when researchers compared those who drank six cups daily to those who drank no coffee at all, the coffee drinkers had a 33% lower risk!
The caffeine in coffee and tea can help with healthy weight maintenance, dull appetite and lower the risk of metabolic syndrome, a cluster of conditions that include obesity, cardiovascular disease and insulin resistance. The catechins in green tea as well as the chlorogenic acid found in green coffee beans can boost thermogenesis, which helps with fat burning.
Your Response to Caffeine is In Your Genes
The way we respond to coffee can depend on our genetics. CYP1A2 is the enzyme primarily responsible for processing caffeine. Variants in this gene determine how quickly we are able to handle caffeine – with some people being fast metabolizers and some being slow metabolizers. Fast metabolizers are at lower risk of the negative effects of caffeine, while slow metabolizers are at a higher risk.
So, whether or not you can safely drink coffee is part of your unique bioindividuality.
What Else Is In Your Coffee Cup?
Aside from the potential drawbacks or benefits of coffee, we also need to consider what else we might be consuming along with it. Coffee is a heavily sprayed crop and we may be ingesting pesticide, insecticide and herbicide residues. Many people don’t drink their coffee or tea black; they load it up with sugar or dairy products.
Let’s not forget we may pair our coffee with refined sugary muffins, cookies, scones, croissants or other baked goods that can impact our health.
Plus, many people get their coffee in take away cups that are often lined with plastic. That’s right, even though they may appear to be made of paper, there is a plastic resin coating to make sure the mug doesn’t break down from the heat.
The Bottom Line: Should We Drink Coffee?
It depends! You’ve just read all about how coffee and other sources of caffeine have both positive and negative attributes.
As caffeine is considered a drug, it’s important to use it responsibly. When I see clients, we work together to scrutinize the why behind the coffee or caffeine consumption. If you’re consistently using coffee to silence fatigue, relieve constipation or increase your focus, I recommend you aim to get to the root of why your struggles are occurring.
If your goal is to build health or lower your risk of developing certain diseases: is drinking coffee the optimal option to help you do that?
For example, if you’re trying to prevent Type 2 diabetes is drinking 3 cups of coffee daily the most effective way to achieve this? I’d say there are far better diet and lifestyle tools you could prioritize first, like cutting out refined sugars, eating loads of vegetables and fruits (especially dark leafy greens and berries), consuming adequate protein and fibre, and choosing nutritious fats.
In other words, if drinking coffee is genuinely a treat you enjoy you can continue to do so mindfully. If you’re using coffee and caffeine as a crutch, as so many of us do, it may be time to break the habit.