The love for coffee runs long and deep for so many of us. I am a coffee lover, too, so I get it. Aside from enjoying the morning ritual, research points to many health benefits of coffee, ranging from brain health to a lower risk of type 2 diabetes. These associations appear to stem from coffee's antioxidants and anti-inflammatory compounds.
But the story isn't so clear-cut when it comes to your hormones. The truth is that coffee, or caffeine in coffee, can affect each person differently. Caffeine is a stimulant, and depending on your health status, genetics, or ethnicity, you may have a harder time processing it and removing it from your body.
You've probably experienced this in some way: two cups send you on a high-energy cleaning frenzy, but your friend drinks a pot a day and can lie down for a nap.
The same nuanced relationship exists between caffeine and your hormones. Caffeine may be a problem for some people, while others can get away with drinking it daily. It's challenging (even for researchers) to pinpoint the exact effect of caffeine on hormones since hormones are so complex and constantly changing throughout your life.
Whether caffeine works for you requires paying attention to how it makes you feel and understanding the situations when caffeine may be a problem for your hormones. Let's look closely at coffee, caffeine, and hormones so you can make an informed choice for your health.
Hormones Impacted by Caffeine
Studies on hormones impacted by caffeine aren't conclusive, but there's some research to consider. Before jumping into specifics, let's explore how caffeine works in your body.
Caffeine keeps you awake (or prevents you from feeling tired) by stimulating your nervous system and blocking adenosine. Adenosine is a neurotransmitter that slows your heart rate and makes you feel sleepy, so when caffeine blocks its receptors, you can feel more energized.
How much and how sensitive you are to the effects of caffeine can vary from person to person. Caffeine metabolism and hormonal shifts differ significantly, even based on your ethnicity.
Your response to caffeine can even shift at different stages of your life. If you're already feeling stressed or burnt out, you may feel differently after drinking coffee compared to times in your life when you feel more rested. These differences are partly why it makes it so challenging to study the impact of caffeine on hormones.
If you usually enjoy coffee and your hormones are already balanced, drinking in moderation is probably okay. Caffeine becomes a problem when it contributes to existing imbalances, meaning it's not usually the cause but rather an aggravator. Below are some ways caffeine may impact your hormones.
Caffeine may affect estrogen levels, but it likely varies between specific populations. In one study, white women who drank more coffee (greater than 200 mg or more than 2 cups daily) had lower estrogen concentrations than those who consumed less. In the same study, Asian women who consumed more than 200 mg of caffeine had higher estrogen levels. Black women also had higher levels, but it was not statistically significant.
Caffeine and estrogen are metabolized by the same enzyme, CYP1A2. This means genetic differences in this enzyme can impact how estrogen and caffeine are metabolized and removed from the body. If you are dealing with estrogen dominance, it could mean you express less than optimal amounts of this enzyme, so extra caffeine may not be a great idea.
There aren't many studies on the effect of caffeine on thyroid hormones. Just like it's not correct to say that everyone with an underactive thyroid needs to follow the same diet, not everyone will respond the same way to coffee. Older animal studies from the 1980s suggested caffeine may inhibit thyroid hormone, but no recent human studies confirm this research.
There are reasons someone with thyroid issues may want to avoid excessive amounts of caffeine (I'll review this in more detail below, including the impact on thyroid medications), but there's no definitive research that ties caffeine and thyroid hormone levels.
Cortisol is a stress hormone linked to your fight-or-flight reaction. It helps you react quickly to danger, releasing glucose into the bloodstream and increasing blood pressure. Short term, cortisol is a good thing and essential for life. But if chronic stress is present, cortisol can remain elevated for too long, affecting many aspects of health, including adrenal function and HPA axis dysregulation.
Hypothalamic–pituitary–adrenal (HPA) axis dysregulation, or what many call adrenal fatigue, can occur after your body has been pumping out stress hormones for too long, resulting in burnout and hormone imbalance.
Caffeine increases cortisol levels, and this influence may be even more significant if other stressors are present. Let's say you're exhausted, stressed, and not sleeping well. Coffee gets you out of bed, and you sip all day to fight off the need for a nap, but then despite all that fatigue, you can't fall asleep at night.
While caffeine may seem to help, it is actually becoming part of the problem. The impact on the central nervous system combined with excessive cortisol, and you've got a recipe for HPA axis dysregulation.
The Optimal Adrenal Kit by Dr. Brighten was designed to help you reset and optimize your adrenal health and overall hormone balance. It supports restful sleep and a healthy stress response, so your energy remains stable throughout the day (without the help of caffeine).
Some research suggests that if you drink coffee regularly, you'll have less cortisol response than someone who never has caffeine—but it will still increase. Caffeine also can exacerbate a normal cortisol response to stress, meaning if your body is already stressed, adding caffeine to the equation makes the cortisol response even higher.
There isn't a lot of science directly connecting caffeine and progesterone. The limited research available from a large study suggests that higher intakes of caffeine are linked to higher levels of progesterone for premenopausal women, specifically in the luteal phase (the second half of the menstrual cycle). This effect wasn't seen for postmenopausal women, so more extensive studies are needed to confirm this relationship.
However what I normally see in clinical practice is the opposite. Possibly the primary way caffeine affects progesterone is through the influence on cortisol and HPA axis dysregulation.
When your body is under stress, it sends signals to slow down the production of sex hormones—including progesterone. Think of this as an evolutionary adaptation where your body recognizes that you likely aren't in a safe place to reproduce. The body down-regulates hormones that facilitate pregnancy and reserves energy to deal with the stressor.
In other words, that cup of coffee isn't necessarily directly impacting your progesterone levels, but the caffeine, in combination with chronic stress, could be depleting your overall experience of adrenal health and lowering progesterone is part of the overall picture.
There are few studies specifically on the impact of caffeine on women and testosterone levels. Studies on men suggest caffeine may contribute to lower testosterone levels, but we can't expand these results to women since our hormones and physiology are much more complex.
Interestingly, another study found that caffeine may lower testosterone in women but increase testosterone in men. Another study found similar results where higher caffeine intakes were linked to lower testosterone in healthy, premenopausal women.
In other words, results are mixed. Whether caffeine lowers testosterone likely depends on the individual.
Hormone Conditions Affected by Caffeine
Based on the above, it's evident that whether coffee and caffeine will add to hormone imbalance is not black and white. However, there are a few hormone conditions to consider that could be affected by caffeine and coffee.
PCOS and Coffee
Polycystic ovary syndrome (PCOS) is an endocrine disorder, meaning it's driven by hormonal imbalances, primarily high androgens (like testosterone) and insulin resistance, which is a loss of sensitivity to the hormone that maintains blood sugar control.
Although the studies above aren't conclusive that caffeine lowers testosterone, it may be tempting for people with PCOS to try and reduce their testosterone levels with coffee. Unfortunately, I often see HPA dysregulation with PCOS, so coffee could make this worse. Caffeine is also linked to increased anxiety in genetically susceptible people, another concern with HPA axis dysregulation.
On the flip side, coffee could be helpful for some people with PCOS because of its potential blood sugar-supporting properties. Drinking coffee is associated with a lower risk of developing type 2 diabetes, possibly related to the anti-inflammatory compounds in coffee.
In other words, people with PCOS who feel good in their bodies and aren't dealing with excess stress or HPA dysregulation (as in, if you don’t feel jittery or anxious, and are sleeping well) may be okay with drinking coffee and might even benefit from the blood sugar and inflammation support. Otherwise, you may want to skip it (or wean down), especially if you struggle with anxiety or adrenal dysfunction.
As mentioned above, the impact of caffeine on thyroid hormones is inconclusive. However, if you take thyroid medication, you should be aware that drinking coffee could interfere with the absorption of your prescription and may reduce its effectiveness. Check with your prescribing doctor or pharmacist to be sure.
Caffeine also increases how quickly food and fluids move through your digestive system, impacting absorption. Waiting 30-60 minutes after taking your thyroid medication before consuming coffee is best. As a bonus, holding off is also better for your adrenal health.
Autoimmune thyroid disease (Hashimoto's), the most common type of hypothyroidism, is closely linked to intestinal permeability (aka leaky gut). People with intestinal permeability are more likely to have food sensitivity and gut issues. Since coffee is a gut irritant (and speeds up gastric emptying), people with gut-related issues should be cautious with coffee consumption.
People living with hyperthyroidism can also experience symptoms like increased heart rate, anxiety, or insomnia—all of which could be exacerbated by Caffeine.
Caffeine and Cognitive Function
I don't want to end this article without mentioning some positives about coffee. As mentioned, the anti-inflammatory compounds in coffee are linked to various health benefits, especially for the brain.
Studies on coffee and Alzheimer's disease are incredibly promising, linking intake of coffee (3 to 5 cups a day) with a decreased risk of dementia or Alzheimer's disease by 65% later in life.
More recent research also found that higher intakes of coffee are associated with slower cognitive decline later in life. The study authors suggest that coffee may help protect against Alzheimer's disease by slowing the accumulation of plaques and oxidative stress in the brain.
Coffee may also help reduce the risk of Parkinson's disease. Multiple studies have found a close inverse relationship between higher intakes of coffee and caffeine and the risk of developing Parkinson's disease. It's thought that coffee and caffeine are neuroprotective but also support motor function for people already living with Parkinson's.
5 Coffee Tips
As long as you don’t have medical issues indicating otherwise, ultimately you get to decide if coffee is good for your body. If you still want to enjoy your cup of coffee, use these tips to offset the negative effects of coffee and decrease the burden on your nervous system and hormones:
1. Choose Organic Coffee
Coffee is heavily sprayed with pesticides, so choosing organic coffee is essential to avoid the extra toxic burden on your body. Luckily, you have so many options available, so you don't have to go to a specialty store.
2. Grind Your Own Coffee Beans
All the antioxidants and anti-inflammatory molecules in coffee are best when fresh. Buying whole bean coffee and grinding it at home as needed gives you the freshest coffee, plus it just tastes better. You don't need anything fancy; a simple grinder works well.
3. Skip the Sugar
Adding piles of sugar (or artificial sweeteners) counteracts the health benefits of coffee, spikes your blood sugar, and can contribute to inflammation. If you make your coffee at home, try adding cinnamon and a splash of cream. Many yummy, non-dairy, unsweetened coffee creamer options made with natural ingredients are also available. Stick with unsweetened options if you purchase coffee from a coffee shop. They add more sugar than you may realize.
4. Make One the Limit
Yes, I know an afternoon cup, shot, or even affogato is divine. But if you've already had your morning cup, try to avoid the temptation. The more caffeine you consume, the greater your body's stress response. If you already drink several cups a day, slowly reduce your intake to avoid feelings of withdrawal like headaches (or switch to green tea or matcha).
5. Make Breakfast a Priority
After a night of fasting, having breakfast with protein and healthy fats helps to stabilize your blood sugar and can help curb cravings. This gives your body the fuel it needs to power through the morning, plus the caffeine won’t slam your system so quickly. A balanced breakfast is essential for hormone balance, and it can help reduce the chance your coffee will lead to an upset stomach.
Need breakfast ideas? My free Hormone Balancing Kit includes a 7-day meal plan and recipes to help you get started with delicious, nourishing meals to support your energy and hormones.
Takeaway: Coffee and Hormones
Coffee can positively or negatively affect our hormones, health, and well-being depending on life stage, genetics, or more. Coffee may support brain health and blood sugar, but there are many other ways to support these health outcomes if coffee doesn't work for you.
For some people, a cup of quality coffee can be a lovely start to the day. But if you struggle with hormone imbalances, chronic stress, or sleep problems, you may want to avoid it—at least for now. If you aren't sure, try experimenting with less coffee and see how your body responds.
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