Lion's Mane and Cordyceps being mixed together by someone wearing a lab coat to create a healthy concoction



Note: Coffee Replacement recipes can be found at the bottom of this article.

Coffee – is it “good” for us, or is it “bad”? Ah, the age old question. Do a quick Google search and coffee aficionados everywhere will be delighted to discover an abundance of research articles at their fingertips, all proselytising with near-rabid excitement the health benefits of drinking coffee. These studies link drinking coffee with reduced risk of diabetes, heart disease, and just about every disease under the sun. If all you did were look at the top search results for research on coffee drinking, you’d be convinced that coffee is a very healthy substance indeed.

Add to this the recent bulletproof coffee craze in which coffee is marketed as the biohacker’s ultimate weapon. Creator Dave Asprey goes so far as to say that bulletproof coffee is “a gateway drug for taking control of your biology”. The butter and coffee concoction is promoted as a breakfast-replacing superfood that not only enhances cognitive performance, but also extends your life span. 

So should everyone be drinking 3-5 cups of coffee a day? Not so fast. One thing that’s important to understand about scientific research is that it deals in averages. In a typical study cohort, there may be a bunch of people who drink coffee and experience reduced risk factors for cardiovascular risk, whilst for others there are increased risk factors. When it comes to answering the coffee question, individual differences are what we should consider, rather than simply “the research”.

In the same way that other current dietary trends (like intermittent fasting, ketogenic or low carbohydrate diets) benefit some people whilst actually deteriorating the health of others, the effects of coffee on health aren’t the same for everyone and depend on a number of very individual factors. These factors include genetics, metabolism, and current health status.

In this article, I’ll discuss the pros and cons of coffee use. I’ll explain how your body responds to coffee intake, the stress response it elicits, and the impacts in various systems of your body. Then you can decide whether or not coffee consumption is right for you, and if you do decide to reduce your intake, I’ll explain how you can do so with minimal unpleasant symptoms.

Caffeine’s positive uses

Let’s start by summing up exactly why coffee is so incredibly popular. 

We live more stressful lives than ever before. Deadlines, traffic jams, high work performance expectations (including being on-call 24/7), and double-income households with kids have become the norm. The accumulation of stress garnered by this kind of lifestyle creates incredible amounts of fatigue; fatigue that stops us from completing all the tasks we feel we need to do to keep our heads above water. In our fast-paced, time-poor society many people don’t believe they have the time or capacity to address the root causes of our fatigue - by say, working less, and resting more. So we look to stimulants.

Caffeine is the most widely used stimulant in western society, and coffee is the most popular vehicle for this stimulant. Caffeine activates the stress response, which is how it enhances short-term performance and concentration. But what most of us forget is that in activating the stress response to experience these “desirable” effects of caffeine, we also get a bunch of other unintended and potentially harmful effects. 

What is the stress response? 

To understand exactly how caffeine affects your physiology, it’s important to understand the stress response. When we take caffeine into our bodies, it stimulates two primary pathways that our bodies possess for responding to acute stress: the sympathetic nervous system (SNS), and the hypothalamic-pituitary-adrenal (HPA) axis. Both of these systems act as biological shock absorbers that help us manage and recover from acutely stressful events. They set up a two-way brain-body communication that either “switches on” or “switches off” the fight or flight response.

The fight or flight response occurs when we find ourselves in critical situations – coming face to face with a tiger is the classic example of this, but getting abruptly cut off in traffic will do it too. 

At the first sign of threat (or perceived threat), the SNS kicks into gear. Adrenaline and noradrenaline are released within fractions of a second, triggering the performance- and focus-enhancing effects coffee is so well known for. Heart and respiratory rates increase. Blood is diverted from the digestive system into the arms and legs to help you fight or flee. Your senses of hearing, sight and smell become keener. You become more alert and vigilant. Your appetite decreases (which is why many people manage to skip breakfast and “get by” on just a coffee in the morning). Immunity is boosted in the case that you are injured by the threat and need to mount an inflammatory response to fight an infection. Growth, digestion, and reproduction are inhibited, as the body diverts resources to immediate life-saving needs rather than “optional” ones. 

The second system, the hypothalamic-pituitary-adrenal (HPA) axis, works slightly more slowly than the SNS, within minutes of detecting the threat. When that car cuts you off in traffic, a part of your brain called the hypothalamus releases a hormone that sets off a cascade that eventually tells your adrenal glands to release cortisol. The pancreas releases glucagon, and together with cortisol, these hormones shunt large amounts of sugar from your muscles and liver into the bloodstream to provide the energy needed for a massive physical response.

Other hormones such as prolactin are secreted by the pituitary gland, which play a role in suppressing reproduction during stress. The stress response also inhibits the release of sex hormones like oestrogen, progesterone and testosterone.

In a natural situation where the fight or flight response is triggered, the adrenaline and increased blood sugar secreted give us the energy to fight or flee and thus survive the threat. Moving our bodies in dynamic ways like sprinting or fighting allow the adrenaline and blood glucose to be used up so that our bodies can return to a state of homeostasis fairly quickly.

However, if we are activating this response when sitting at our desks or driving our cars, our muscles remain stationary - aside, perhaps, from those of your middle finger in traffic!. We don’t have a chance to “burn up” the sugar, and fully utilise the many hormones and neuroendocrine mediators that are being pumped out. Instead, the stress hormones and blood sugar remain in our systems for much longer. Interestingly, when the body finally gets a chance to recover from the acute stress, it responds to the need for repair by increasing appetite and storing fat (mostly in the abdomen). 

Prolonged stress

Prolonged and repeated exposure to acutely stressful events (and the anticipation of such events, like anxiety about those overdue bills you need to pay) can override the body’s capacity to fully recover to the point where the body’s shock absorbing systems can no longer stay on top of the wear and tear. The deterioration that your body experiences as a result of chronic exposure to an activated stress response is called allostatic load.

Allostatic load can lead to HPA axis dysregulation, where the HPA axis either cannot turn off, or cannot turn on the stress response. 

People who cannot turn off the stress response will pump out disproportionately large amounts of adrenaline as if they were in a chronic state of fight or flight. These people can experience relentless anxiety, agitation, and insomnia. Other people experience this as cortisol dominance which shows up as increased cravings for salty, fatty and sweet food, weight gain around the waist, and generally having more negative, stressed out thoughts. 

If your allostatic load becomes too great, your body may actually turn down the adrenals in an effort to protect you from this wear and tear. Instead of having an overactive stress response, your HPA axis now does the opposite - you produce lower than normal levels of cortisol and adrenaline.

Although these are “stress” hormones, we still need a certain level of cortisol and adrenaline to stay healthy. If levels are too low, your immune system becomes compromised and you may feel more aches and pains. This can manifest as a chronic condition called fibromyalgia.

Because cortisol helps us feel awake and refreshed in the morning, low cortisol levels mean that you will feel exhausted no matter how many hours of sleep you’ve had. Waking up in the morning becomes increasingly difficult, and you might find yourself crashing mid-afternoon, or even all day long. Digestive problems, anxiety and overall stress usually get worse the longer the cortisol deficiency continues. 

Caffeine and the stress response

So what does coffee have to do with all of this? Caffeine looks like adenosine, a naturally occurring neurotransmitter in the brain that helps us feel sleepy, especially at nighttime before bed. Caffeine binds to adenosine receptors on the surface of nerve and brain cells, but instead of making us sleepy like adenosine would, caffeine actually causes increased neuron firing. The HPA axis (in particular, the pituitary gland) senses this activity and interprets it as some sort of emergency, so it releases hormones that tell the adrenal glands to produce adrenaline. 

Caffeine triggers the acute stress response just as if a tiger has just jumped out in front of us, which is why we experience those “benefits” of sharper focus and performance. Regular intake of caffeine creates a pattern where our bodies are repeatedly pushed into fight or flight mode, but without necessarily providing the “tiger” to motivate us to physically run or fight - actions that would dissipate the chemicals and sugar released in that stress state.  

Caffeine allows us to push past our natural energy limits, which may be useful for short-term athletic performance and concentration. But if we repeat this pattern multiple times a day, day after day, our endocrine and nervous systems get tired of working so hard every time we ingest caffeine. With time, your ability to produce adrenaline may decrease, and the hormones of the HPA axis become dysregulated, especially cortisol.

Contrary to popular belief, caffeine does not give us energy; rather, it masks tiredness by pushing us into an adrenalised “survival” state. This explains why people often experience even deeper states of fatigue and depression once a caffeine-induced adrenaline high wears off.

If we are drinking coffee multiple times per day, we are triggering the acute stress response over and over again, which can set us up for HPA axis dysregulation, overdrive, and eventually exhaustion.

The downsides of caffeine use

It’s one thing to use caffeine in one-off situations, competing in a marathon perhaps, or to improve your concentration when sitting an important exam. But because of its impact on the acute stress response, in combination with its addictive quality, few people reserve coffee drinking for only these rare occasions. With persistent overuse, caffeine has a number of serious negative health impacts that need to be considered:

  1. Caffeine can cause or exacerbate anxiety. Because it stimulates the stress response, caffeine can create and even worsen anxiety over time (1). Anxiety disorders are one of the most common forms of mental illness in western countries, with chronic anxiety affecting around one in five Australian adults (2). Remember, that statistic only counts those who have been diagnosed. Many more people experience high levels of stress and anxiety on a regular basis, even if they’re not seeking active treatment for it. 
  2. Caffeine can create and worsen HPA axis dysfunction. As previously mentioned, regular caffeine intake creates a persistently activated stress response, which can lead to HPA axis dysregulation and the associated fatigue, hormonal, mental and immune issues. If stress and the HPA axis dysfunction it elicits both continue, this may lead to chronic fatigue.
  3. Caffeine abuse can contribute to chronic fatigue syndrome (CFS) and cortisol dominance. HPA axis dysfunction is often the root cause of chronic fatigue. Chronic fatigue syndrome (CFS), once considered a fringe diagnosis, is now becoming a more accepted medical diagnosis albeit with a new name: Myalgic Encephalomyelitis (ME) (3). Once a person is in a state of HPA axis dysfunction, chronic fatigue may be just around the corner. In this state, the long-term stress hormone cortisol becomes dominant. While it has some helpful functions, persistent cortisol levels reduce immune function, blood sugar imbalances which can lead to insulin resistance, and can create thyroid and sex hormone imbalances.
  4. Caffeine suppresses thyroid function. High cortisol levels down regulate thyroid hormones (3). Additionally, a chronically activated stress response reduces the sensitivity of thyroid receptors. This can lead to hypothyroid symptoms like depression, dry skin, fatigue, hair loss, and weight gain.
  5. Caffeine disrupts sleep cycle and circadian rhythm. Remember adenosine? It’s an important neurotransmitter for sleep, and especially to deep sleep. Caffeine blocks the action on adenosine and interferes with our quality of sleep. Depending on how long it takes your body to break down caffeine, you may be able to have a coffee at lunchtime and fall asleep that night easily – or you may not. The half-life of caffeine varies greatly between individuals, anywhere from 2 to 10 hours! (4). If you’re a slow metaboliser of caffeine, having a big cup of coffee mid-morning could significantly affect your body’s ability to experience deep, restful sleep. You wake up tired, and reach for another coffee. And so the fatigue and sleep deficit accumulates, and the dependence on coffee to stay awake grows. Given that the number of people in western society who get fewer than six hours per night is increasing, widespread caffeine consumption may well have wide-ranging societal implications (5). 
  6. Caffeine causes sex hormone imbalances. Because of its capacity to contribute to HPA axis dysfunction and cortisol dominance, regular caffeine intake can affect the delicate balance of your reproductive hormones, including oestrogen, progesterone, and testosterone. Sex hormones and cortisol all require the same basic building block: cholesterol. When you’re constantly activating your stress response your body diverts hormone production away from making oestrogen, progesterone, and testosterone into making more cortisol. When this occurs, women are more likely to experience menstrual difficulties such as severe PMS, irregular or missing periods, which can contribute to infertility. Additionally, coffee can directly increase levels of sex hormone binding globulin (SHBG), a protein that binds to oestrogen and testosterone in the blood (6). The body cannot use sex hormones when they are bound to SHBG.
  7. Caffeine can upset digestion. Caffeine switches on the fight or flight response, which basically stops digestion in its tracks. No one wants to waste energy digesting when they have to fight off a tiger! A gut that is not moving, coupled with higher levels of adrenaline-induced anxiety, can set you up for chronic gas, bloating, digestive discomfort, and irritable bowel syndrome (IBS). These symptoms may be due to microbiome and intestinal wall changes that that occur when gut function is impacted by acute stress for too long. 

So do I give it up completely, just cut back… or keep enjoying my daily bulletproof coffee?

Before we make any decisions about coffee, the most important question to ask is, “does it work for me?” Whether you’re using it to sharpen focus and concentration, improve sports performance, or simply to feel more energised, does it fulfil the intended purpose with minimal to no negative side effects? Answering these questions necessitates paying attention to what’s happening inside your own body. This kind of mindfulness will give you more answers than any scientific study. 

Observe your body during and after you drink coffee. Does your breathing become more rapid, and are you comfortable with that? Do your muscles tense up? How you feel immediately afterwards, a few hours later, and later on in the day? What is your quality of sleep like that night? Do you feel hyper-stimulated, jittery, anxious or overly wired after drinking coffee? 

You may drink your daily cup of coffee and experience mental clarity, have no troubles falling asleep and no signs of HPA axis dysfunction, in which case coffee might not be affecting you negatively. Or you may feel sweaty, extremely nervous and unable to fall asleep hours after having just one coffee. 

If you’re using it to enhance sports performance, is it actually working for you? Even though caffeine is used by many athletes to lower perceived exertion and increase power output, individual variability should still be considered. Exercise physiologist Stacy Sims reports, “I’ve seen athletes experience big heart-rate and blood pressure swings and become too amped to focus even with low doses (of caffeine).”

Individual variability

Perhaps you’re so used to drinking coffee that it’s difficult to discern which bodily sensations are normal and which are caffeine-induced. If this is the case, you can think about a few other factors to determine whether or not coffee is right for you: 

  • Caffeine sensitivity. Genetic factors dictate how well you tolerate caffeine, specifically how quickly your body breaks down caffeine. Your caffeine sensitivity is dependent on the capacity of phase I detoxification in your liver, where it is metabolised by an enzyme encoded in the CYP1A2 gene. You could be a slow or fast metaboliser of caffeine depending on this gene. If drinking a cup of coffee leaves you anxious and jittery, or keeps you awake for days, chances are you are a slow metaboliser. Coffee consumption by slow metabolisers is associated with a higher risk of heart disease (7), high blood pressure (8), and impaired fasting blood glucose (9). If you are curious, you can order genetic testing that will identify you as a slow or fast metaboliser.
  • Stress levels and tolerance. When you’re run down and fatigued, caffeine can be harder for your body to handle. A high allostatic load impairs many body functions including liver detoxification and digestion, which may make you more sensitive to caffeine. If you’re healthy and sleeping well you may be able to drink coffee during the day without ill effects. But if you’re not 100% in these departments, coffee could just make things worse.
  • Current health status. Do you have PCOS, an oestrogen dominant condition (e.g. endometriosis) or other some other thyroid or sex hormone imbalance? Do you have IBS, fibromyalgia, an autoimmune disease, or another chronic illness that’s really stressing your HPA axis? If so, the stimulating effects of caffeine may be too much for your body to handle and may worsen these conditions.
  • Coffee quality. Pesticide-grown coffee beans are one of the most chemically treated crops - an average acre of conventional coffee is sprayed by over 100 kilograms of chemical fertilisers. A daily coffee made with conventionally grown coffee beans, non-dairy creamer and artificial sweetener is probably going to have a greater toll on your health than say an organic coffee with full fat milk or cream.

How to cut back on caffeine

Maybe you’ve decided that you don’t love the feeling of uneasiness or jitters coffee gives you, a feeling many of us mistake as increased energy. Or maybe you recognise some of those health issues mentioned earlier and you’re curious to see if cutting back on coffee can help alleviate your symptoms. 

It’s no secret that the withdrawal symptoms from suddenly quitting coffee can be unpleasant. Headache, fatigue, irritability, anxiety, difficulty concentrating, and flu-like symptoms like nausea, vomiting and muscle pain or stiffness are common when going cold turkey (10, 11). These symptoms usually occur 12 to 24 hours after you completely stop consuming caffeine. They peak in their intensity between one and two days, and all up may last for two to nine days. Of course, the higher your daily caffeine dose, the more unpleasant you can expect the withdrawal symptoms to be. These symptoms may even occur when quitting relatively small doses of coffee, say one small cup of coffee (100mg caffeine) a day (12).

But it’s not all doom and gloom! Instead of going cold turkey, taking a stepwise approach is a more humane way to come down from caffeine without suffering the more severe withdrawal symptoms. You can make the process even more comfortable – and dare I say, even pleasant – by incorporating some nutritive and regenerating caffeine replacements. This gentle approach can eliminate the cravings for your usual coffee fix while beginning to repair any damage caffeine may have done.

How long will this process take? Two to four weeks depending on how much coffee you’ve been drinking. Try reducing the your overall caffeine intake by half. If you’re a 4-cups a day coffee drinker, that might look like:

  • going from 4 cups of coffee per day to 2 cups
  • swapping 2 regular cups for decaf coffee or green tea instead
  • incorporating some non-caffeinated beverages such as herbal tea.


Coffee alternatives

Fatigue is often the main reason people are hesitant to move away from caffeine-dependence. Folks wonder how they will get through their workday – or life - without it. Many of the clients I see in my clinic rely on caffeine to fight fatigue, without addressing the stress that’s causing their fatigue in the first place. Rather than using coffee to manage low energy levels, a better approach would be to address the underlying causes of your fatigue. 

As you work on addressing the life stressors that are bringing about your fatigue, you can simultaneously nourish, support and rebalance your nervous and endocrine systems with tonifying herbs. 

Here are some wonderful alternatives to coffee that can not only be used as coffee alternatives, but have veritable health benefits and support natural energy levels without taking a toll on your body:

  • Tea (Camillia sinensis) High quality black and green teas contain theanine, a compound, which actually promotes relaxation (13). Theanine has been shown to counteract some of the stimulant effects of caffeine, perhaps one of the reasons that caffeine sensitive people can enjoy tea without the typical caffeine response. Finally, despite still containing some caffeine, it sis much less than coffee; the average cup of coffee contains 135mg of caffeine versus 40mg in a cup of black tea, and 20mg in a cup of green tea.
  • Bitters such as roasted dandelion (Taraxacum officinale) root. This herb can help prepare your body for digestion, and stimulates liver detoxification. Chicory root works in a similar way.
  • Anxiolytics such as kava (Piper methysticum) and passionflower (Passiflora incarnata) may offer temporary relief for the anxiety that can arise during caffeine withdrawal (14). They are also wonderful ways to help you stay calm and centred in daily life.
  • Adaptogens are a special class of herbs that have been used in Ayurveda and Tradition Chinese Cultures for thousands of years, to promote a sense of wellbeing. Adaptogens do just that – they help your body adapt to the ongoing stresses of daily life. They regulate the stress response, increase energy, and most of them are non-stimulating (with the exception of Korean ginseng) (14).  Adaptogens work best when they are taken for a minimum of three months. Examples include, but aren’t limited to:
    • Ashwaganda (Withania somnifera) – traditional used in Auervedic Medicine as an adaptogen, helping the body adapt to stress.
    • Siberian ginseng (Eleutherococcus senticosus) – a focus and performance enhancer. Avoid with high blood pressure; and if you’re prone to insomnia use a different adaptogen (14).
    • Adaptogens don’t only come in the herb form; a few mushrooms are also powerful adaptogens, such as chaga (Inonotus obliquus), try our recipe here. Chaga tastes very similar to coffee and is enjoyed by people in Russia and Siberia as a daily drink. It was even used as a coffee replacement during World War 2 when food shortages were the norm.

Other ways to smooth out your venture away from coffee include keeping blood sugar levels stable with regular and balanced meals, creating or maintaining a regular mindfulness and meditation practice, enjoyable exercise, staying hydrated, and getting adequate sleep.

The benefits of reducing your coffee intake are huge. Even if you don’t quit entirely, you may find that you need less caffeine than expected to wake up in the morning, and you may start to experience more natural energy and less anxiety. Your thinking can become clearer as your sleep patterns start to regulate. And if you have any of the hormonal conditions described earlier, you can expect improvements in your health the longer your body stays off this potent substance.

Written by Casey Conroy
Casey is a holistic dietitian (APD), Credentialed Eating Disorder Clinician (CEDC), Yoga & Movement Teacher and 4th year student Naturopath. She offers 1-on-1 consultations virtually and on the Sunshine Coast. You can find her at


  14. Bone, K (2007), The Ultimate Herbal Compendium,1sted, Phytotherapy Press, Warwick.

1 comment


Really great read!

About three months ago, I finally decided it was time for me to quit coffee, atleast temporarily, as I had began to notice during meditation after my morning coffee that I could feel the stress coursing through me.

In conjunction with going to a doctor and finding out about HPA Axis disregulation and how that had been affecting me, and taking steps to recover, I find that my decision has been a great move forward.

I have had probably two coffees in my ‘quitting’ time, and I could notice that I was better without it.
Although after a few weeks of no caffeine at all, I ended up getting more into chai, which is great, but now I think it’s time to have no caffeine.

I have also been researching medicinal mushrooms and adaptogens and comparing brands.

You guys look like you have a great product and ethical values to match!

Looking forward to reading more on your blog in the future, and enjoying the benefits of your supplements.


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