How to Tell if Coffee is Good or Bad for You.
Let's talk about coffee and the healthy/unhealthy relationship that you may have with it.
We can't seem to decide whether coffee is good or bad for us, and that's because the answer truly is that it depends.
There are studies which show the benefits of coffee for cognitive function, metabolism, and energy levels and there are also studies which show the negative effects of raising blood pressure, increasing anxiety, disrupting sleep patterns and causing headaches.
How can coffee be both good and bad for you?
Well, in order to understand how, we must look into a few things…
First we will go over the science behind it all, then we will touch on your coffee quality and finally your overall relation with the stimulant.
Coffee lovers, it's time to learn how you can create a much needed balance in your relationship with the world’s favourite stimulant.
The effects of coffee are different for everyone and this is due to our own unique metabolism. After you take a sip of coffee, it takes only 5 minutes for the caffeine to initially be absorbed into the bloodstream, after 45 minutes 99% of the caffeine will be fully absorbed. Effects of caffeine can last anywhere from 4-6 hours on average. The speed at which caffeine is metabolized depends on your specific gene makeup (yes, your coffee drinking ability is in your DNA).
Since 2.25 BILLION cups (that's with a B) of coffee are made each day in the ENTIRE WORLD. A habit so common, must be over analyzed. It’s the actual caffeine metabolism side of things that I want to touch on today. Aren't you even just the slightest bit interested in knowing how some can drink a cup of coffee and go to sleep within the same hour and how others can get jittery and anxious off just a sip?
Caffeine is classified as a drug, it stimulates the central nervous system and your body also metabolizes it like one. Caffeine is not stored in the body - 24 hours after consumption it is excreted. Your lovely liver is what metabolizes the caffeine, along with other toxic substances that we may ingest in a day.
Your ‘phase 1’ and ‘phase 2’ of liver detoxification are active in transforming toxins that we ingest (including caffeine), into a less-toxic form - which can now be safely excreted. YAY for your body!
Now before we go any further into detox talk - just as newly discovered planets end up with names such as Kepler-186f, enzyme names are also pretty technical, so don't stress memorizing or even comprehending the enzyme names i'm about to drop in the next few sentences.
When it comes caffeine metabolism, an enzyme called CYP1A2 does the work. This enzyme is a part of the cytochrome P450 'superfamily' and it plays a large role in your phase 1 of liver detoxification. This is the phase where alcohol, drugs, medications and of course caffeine are converted into their less-toxic form that is more, 'water soluble', and can now be excreted.
This family of P450 enzymes also play a role in producing cholesterol, steroids, fatty acids and vitamin D. (Isn't your body amazing). 
This enzyme called CYP1A2 is the also key player in whether you are a fast, or slow, caffeine metabolizer.
We all have two copies of the gene which makes up the enzyme ‘CYP1A2’, we get one copy from each parent (thanks mom & dad!). Just as your parents genes determined you hair colour and eye colour, they also were responsible for your caffeine metabolism (thanks mom & dad?). There are 2 variations of this gene which will affect how quickly a person metabolizes caffeine 
CYP1A2*1A metabolizes caffeine very rapidly
CYP1A2*1F metabolizes caffeine slowly
The difference between these two variants is one single nucleotide. Meaning one measly, single building block in your DNA determines your true relationship with your ability to ‘handle’ caffeine.
Now. Most of us don’t know which gene variation we have. But you can undergo genetic testing to see if you and coffee are a true match made in heaven. Both Nutrigenomix and 23andMe provide genomic testing which can tell you where exactly your DNA structure falls. This is valuable information to know, especially if you are consuming more than one cup of coffee a day.
Those who metabolize caffeine more slowly are much more susceptible to complications associated with high blood pressure and may have an increased risk of heart attack. Slow caffeine metabolizers should not drink more than one cup of coffee a day - and if you don't know where your genetic makeup stands (and don't want to pay to find out), then you're best off just having just one cup a day .
You know, limiting yourself to a few coffees a week and no more than one a day, in my own opinion, is the healthiest habit to form with caffeine. Use its benefits for when you truly need them. But when and if you do reach for your cup-a-joe, remember another important choice is the quality of the bean.
You see, you can actually get some nutrition from your coffee (it’s made up of more than just caffeine) - when you choose certified organic varieties.
"You mean I have to buy organic coffee!?", well - yes! You should, and it’s not hard to get your hands on these days.
Coffee is actually one of our most heavily sprayed crops. Since this bean is mass produced (2.25 billion cups per day), choosing organic ensures that your coffee is not saturated in pesticides - which would make for a chemical cocktail in your morning cup.
Organic, fair-trade coffee also tastes better, most are less bitter - and the true flavours of origin come through in a wonderful way. Some coffees have more of a vanilla undertone, while others take on berry or citrus flavour (true coffee lovers know).
Picking 'fair-trade' will also equal good karma. Many coffee farmers make little to no money from their hard work, and fair-trade means that the coffee farmers that work hard everyday to produce your java are making a fair living. Buying organic and fair-trade means there will be no artificial flavours added and no chemicals are used in the processing.
Coffee beans naturally contain magnesium, B vitamins, zinc, copper, and minerals from the healthy natural/organic soil that they grow in.
While there is lots to consider with our coffee habit, the biggest takeaway is do not let coffee rule you, premium organic coffee, with no dependency can definitely add some bonus points to your day (for cognitive function and energy), ideally you would be a fast metabolizer and not sensitive to stimulants.
On the flip side, an unhealthy habit is one where dependency on coffee is present and you cannot function without it. This is a tell tale sign of poor adrenal function. Caffeine stimulates your adrenal glands which puts you into a constant fight/flight response. Caffeine does create dependency and you must always remember that when you drink coffee, you are not really getting energy, you are borrowing energy from caffeine. So if your top reason for consuming coffee is because you cannot function without it than some underlying work needs to be done.
I highly recommend following a 14-Day Coffee Elimination Challenge to eliminate any dependency that you may have developed.
You don't have to give up coffee! Just make the healthiest choices that benefit your body as whole.