Apr. 15. 2016
McKel Kooienga, MS, RDN, LDN

McKel Kooienga, MS, RDN, LDN

Dietitian, Founder and CEO

Is coffee unhealthy…or not?

As a Registered Dietitian Nutritionist, I’m asked questions like this all the time and seeing what goes on in the wellness digital space can sometimes be comical. I often see trends and dogmas being repeated and thrown around and then taken as fact. Let’s strip this myth once and for all. Is coffee unhealthy…or not?

“In this series, I’m stripping away the fluff around these nutrition and healthy living myths, dogmas, and practices from reading your submissions to our inbox. Join the conversation and share in the comments why/if you went along with this myth.”

Is coffee unhealthy…or not?

Did you know that the average Americans drinks about 3 cups of coffee a day? (5) Coffee is the primary source of caffeine in our diet. Although numerous studies show drinking coffee can improve health from lowering risk of certain types of cancer, Parkinson’s disease, obesity, type 2 diabetes, metabolic syndrome, and heart disease, caffeine in coffee might not be great for everyone. Other than the “pH acidic theory”, when did coffee get such a bad rap? Advocates and gurus who shy away from coffee consumption purely based on the fact that it’s “acidic” leave me wondering if they know what our bodies actually do to control pH balance in the body. Yes, coffee is acidic and foods do contribute to an overall alkaline or acidic ash in our bodies, but we have to give our bodies more credit here. Our bodies tightly regulate our pH levels and, yes, food can affect this. One cup of coffee may show up “acidic” in a urinary analysis (or using urine strips to test), but those results don’t support the theory in full, plus urine strips aren’t a great measure of our overall body pH (more on the acid vs. alkaline diet theory later) (9). However, abstaining from coffee because of individual preference or your sensitivity to it – well, that’s another story to dive into with some credibility. For most of us, though, just because coffee is acidic doesn’t mean it’s unhealthy for us. That isn’t a pass to guzzle five cups of coffee a day, though, as there are some problems that come with drinking coffee or too much coffee.


No. 1: The quality and how it was grown
I’ve spoken before about my recommendation to only use fair trade and organic sources of coffee (and chocolate) to make sure you’re supporting healthful labor practices, but organic also ensures high-quality coffee beans. I have my favorite brands listed at the end of this post and how to use it. Coffee is one of the most heavily sprayed crops with pesticides, so choosing high-quality coffee ensures that you aren’t adding harmful chemicals and toxins to your body.

No. 2: Caffeine and your dependency on it
I never knew how much I relied on the caffeine in coffee to “wake me up” for the day until I was laying in bed one Sunday morning and I just wanted to sleep in. Yet what interrupted my plans for sleeping in was this pull to the kitchen to get coffee. It was at that point I realized how caffeine can have dependency and addictive qualities. I cut out coffee cold turkey that day and only started integrating it back into my diet a couple of years ago. I’m sharing my experience with you to test you and encourage you to ask yourself, “what would happen if I cut out coffee?” Do you know what you feel like without caffeine/coffee? For this reason, I recommend cycling (3) caffeine and coffee use to keep your body in check.

No. 3 Stress and anxiety
Caffeine from coffee is a stimulant and great for post-workout for some individuals, but on the other hand, if you suffer from anxiety or are living with high stress, coffee isn’t for you (4). On the flip side, caffeine has also been shown to help decrease depression and symptoms of anxiety, although those studied were probably “fast metabolizers” and not your average person. If you struggle with depression or tend towards anxiety, try cutting down on coffee and see if you notice a difference in the way you feel.

No. 4: Hormonal health
I’m fascinated with the role our hormones like cortisol play in our bodies. Cortisol is an interesting hormone (we’ll be talking more in depth later on this one) that increases when your body is under physical/mental/emotional stress. Increased cortisol is a normal stress response, but what’s not normal is chronically high levels of cortisol. Caffeine found in coffee can exacerbate stress and increase cortisol levels, so again, if you’re a sensitive individual be mindful of this. Cortisol in particular has this tricky way of throwing off our delicate hormonal balance. Dr. Sara Gottfried calls this phenomenon the “progesterone steal” and explains how it may not be the best to consume for those with thyroid issues (15).  Also, if you want to nerd out about this process, Dr. Sarah Ballantyne is also a great resource on hormones (2).

No. 5: Sleep
Are you burning the candle at both ends? Emotional, physical, mental stress, chronic illness, not sleeping well, or not following your self-care routine? You could be more sensitive to caffeine under these times of stress on the body. Be mindful and listen into what your body is telling you. If you feel worn down, coffee might be too much and exaggerate your symptoms, especially when consumed closer to the late afternoon/evening times. Some people show that caffeine doesn’t affect sleep at all, whereas others couldn’t sleep after drinking caffeine late in the day (8). This just goes to show we’re all unique and we have to find what works for us. Listen to your body and if you notice that caffeine late in the day keeps you up or causes restless sleep, limit it after noon or so.

No. 6: Your DNA
Our liver does many things and metabolizing caffeine is one of them. Some of us are “slow metabolizers” of caffeine (due to a gene called CYP1A2), which basically means you process caffeine slowly which can increase your chances for impaired fasting glucose (6), heart disease (1), and hypertension (7). Some of the health benefits listed in this post also are closely related to the “fast metabolizers” among us, so if you think you might be slow metabolizer (again, listen to your body), consider cutting down on the amount of caffeine you drink.

No. 7: Nutrient absorption
Caffeine can also affect your body’s absorption of minerals such as iron and zinc which may lead to iron deficiency anemia (10). If you think you might have a mineral deficiency, read up more on that topic here and consider getting blood tests done by a doctor.

Now that I’ve detailed how caffeine might negatively affect your body and your health, it’s time to get to the good part. Read below for how coffee might be good for you.

Potential Benefits of Drinking Coffee: 

No. 1 Cancer
Coffee may help reduce the risk for certain types of cancer including prostate, liver, breast, gastric, and colorectal.

No. 2: Diabetes and metabolic syndrome
In this case, coffee may help improve blood sugar control and reduce weight just by drinking 1 1-1/2 cups of coffee a day. (11) (12) (14)

No. 3: Inflammation
Coffee has been associated with reducing inflammation (16), oxidative stress (17), and HDL cholesterol.

No. 4: Mental and athletic performance
Caffeine increases blood flow and circulation to the muscles, and since it’s a stimulant you can guess this would give you a jolt in the gym. Some studies have shown that you can burn 15% more calories with a pre-workout cup of coffee (18). On the mental/emotional front, some studies have shown that depression decreases with increases in caffeine (but these could be the “fast metabolizers” we discussed earlier). (13)

The verdict:

Coffee isn’t “bad” for you or unhealthy, but sensitive individuals should be mindful of the caffeine levels in their diet and listen to their body especially during stressful periods in life. I personally love coffee, but there’s a fine line between enjoying it in moderation and triggering my migraines. I typically cycle off for 3 weeks at a time to give my body, hormones, and adrenals a break. If you do love coffee, be sure to purchase only from organic and fair trade producers like this one in the NS Shop and also listen to how your body functions on caffeine.

Take action. Want to test getting “off the coff”? Try this:

  • Day 1: consume your normal amount, for example 1 cup
  • Day 2: cut down 1/4 cup, for example drinking 3/4 cup
  • Day 3: cut down 1/4 cup
  • Day 4: cut down 1/2 cup, for example drinking 1/2 cup
  • Day 5: cut down 1/2 cup
  • Day 6: consume only 1/4 cup, for example drinking just a small amount
  • Day 7: your done, replace with the following recipes!

Replace your coffee with these:

Coffee lovers unite and try these nutrient-dense recipes:


Have you ever followed this myth? Leave a comment and let’s chat! And if you’d like more guidance from a nutrition expert on how much coffee you should be drinking for your health and wellness goals, sign up here for a 1-1 nutrition consult.

xx McKel


(1) Cornelis MC, El-Sohemy A, Kabagambe EK, Campos H. Coffee, CYP1A2 genotype, and risk of myocardial infarction. JAMA. 2006 Mar 8;295(10):1135-41. PubMed PMID: 16522833.
(2) http://www.thepaleomom.com/2014/08/chronic-stress-leads-hormone-imbalance.html
(3) http://examine.com/faq/do-i-need-to-cycle-caffeine/
(4) Broderick P, Benjamin AB. Caffeine and psychiatric symptoms: a review. J Okla State Med Assoc. 2004 Dec;97(12):538-42. Review. PubMed PMID: 15732884.
(5) http://www.hsph.harvard.edu/news/multimedia-article/facts/ | National Coffee Drinking Trends 2010, National Coffee Association
(6) Palatini P, Benetti E, Mos L, Garavelli G, Mazzer A, Cozzio S, Fania C, Casiglia E. Association of coffee consumption and CYP1A2 polymorphism with risk of impaired fasting glucose in hypertensive patients. Eur J Epidemiol. 2015 Mar;30(3):209-17. doi: 10.1007/s10654-015-9990-z. Epub 2015 Jan 17. PubMed PMID: 25595320.
(7) Palatini P, Ceolotto G, Ragazzo F, Dorigatti F, Saladini F, Papparella I, Mos L, Zanata G, Santonastaso M. CYP1A2 genotype modifies the association between coffee intake and the risk of hypertension. J Hypertens. 2009 Aug;27(8):1594-601. doi: 10.1097/HJH.0b013e32832ba850. PubMed PMID: 19451835.
(8) Penolazzi B, Natale V, Leone L, Russo PM. Individual differences affecting caffeine intake. Analysis of consumption behaviours for different times of day and caffeine sources. Appetite. 2012 Jun;58(3):971-7. doi: 10.1016/j.appet.2012.02.001. Epub 2012 Feb 9. PubMed PMID: 22326679.
(9) Remer T, Manz F. Potential renal acid load of foods and its influence on urine pH. J Am Diet Assoc. 1995 Jul;95(7):791-7. PubMed PMID: 7797810.
(10) Muñoz LM, Lönnerdal B, Keen CL, Dewey KG. Coffee consumption as a factor in iron deficiency anemia among pregnant women and their infants in Costa Rica. Am J Clin Nutr. 1988 Sep;48(3):645-51. PubMed PMID: 3414579.
(11) Shilpa Bhupathiraju et al. Changes in coffee intake and subsequent risk of type 2 diabetes: three large cohorts of US men and women. Diabetologia, April 2014 DOI: 10.1007/s00125-014-3235-7
(12) Rustenbeck I, Lier-Glaubitz V, Willenborg M, Eggert F, Engelhardt U, Jörns A. Effect of chronic coffee consumption on weight gain and glycaemia in a mouse model of obesity and type 2 diabetes. Nutr Diabetes. 2014 Jun 30;4:e123. doi: 10.1038/nutd.2014.19. PubMed PMID: 24979152; PubMed Central PMCID: PMC4079928.
(13) Lucas M, Mirzaei F, Pan A, et al. Coffee, Caffeine, and Risk of Depression Among Women. Archives of Internal Medicine. 2011;171(17):1571-1578. doi:10.1001/archinternmed.2011.393.
(14) Effects of coffee consumption on subclinical inflammation and other risk factors for type 2 diabetes: a clinical trialAm J Clin Nutr 2010 ajcn.28548; First published online February 24, 2010.doi:10.3945/ajcn.2009.2854
(15) http://www.saragottfriedmd.com/coffee-hijacks-thyroid-levels-2/
(16) http://ajcn.nutrition.org/content/early/2010/02/24/ajcn.2009.28548.abstract#_jmp0_
(17) Hori A, Kasai H, Kawai K, Nanri A, Sato M, Ohta M, Mizoue T. Coffee intake is associated with lower levels of oxidative DNA damage and decreasing body iron storage in healthy women. Nutr Cancer. 2014;66(6):964-9. doi: 10.1080/01635581.2014.932398. Epub 2014 Jul 25. PubMed PMID: 25062326.
(18) Fernández-Elías VE, Del Coso J, Hamouti N, Ortega JF, Muñoz G, Muñoz-Guerra J, Mora-Rodríguez R. Ingestion of a moderately high caffeine dose before exercise increases postexercise energy expenditure. Int J Sport Nutr Exerc Metab. 2015 Feb;25(1):46-53. doi: 10.1123/ijsnem.2014-0037. Epub 2014 Jun 5. PubMed PMID: 24901809.