Health and Coffee pt. 8: Metabolism

By Julianne Bierwirth, RD


Coffee has a chemical complexity that, through the roasting process, creates a broad range of vibrant flavor characteristics. This same molecular diversity is also responsible for a variety of health effects in humans. Caffeine is certainly the most well-studied, but it is far from the only pharmacologically active molecule extracted during a brew. Some of these chemicals are elusive, and their effects poorly understood. Others, after decades of research, have concrete benefits and detriments firmly borne out by data.

In this 8-part blog series, we delve into the myriad truths, half-truths, and indeed, fallacies, related to the impact that coffee has on your health. Is it good for you? Is it bad for you? Is it going to make your teeth brown? Does coffee make you smarter? Read on to find out.


Our nation has seen a growing epidemic of obesity in adults and children over the last thirty years. As a result, food, pharmaceutical, and supplement companies have very profitably marketed all kinds of foods with the promise of boosting metabolism. This idea of increasing metabolism has been inextricably linked with weight management in the public mindset. Coffee and caffeine have become common ingredients in these weight-loss products, but before we discuss their efficacy, it’s worth understanding what metabolism actually is and how it rises or falls in individuals.

What is Metabolism?

Metabolism is the umbrella term used to describe the chemical processes by which the body harvests energy to keep itself alive. It includes catabolism (the breakdown of oxygen and chemicals in food to produce energy) and anabolism (the use of these chemicals to rebuild and maintain the body).

If you hear people talk about metabolism it may seem like an internal thermostat that can be set higher or lower by genetics or age. People will often complain that they suffer a slow metabolism and therefore have trouble losing weight, or that they have a fast metabolism and therefore have trouble gaining muscles mass.

It is true that some people have genetically different thyroid activities, or else glean fewer calories from their food due to gastrointestinal function. Hunger, satiety, and energy expenditure are complicated chemical processes, however the energy equation does not change for anyone. If you take in more calories than you burn, you will gain weight. If you burn more than you take in, you will lose weight.

Caffeine may work on both ends of this equation: increasing the amount of energy you burn and decreasing the amount you eat.

Do people who drink coffee eat fewer calories?

There is some evidence to support this idea. Studies have demonstrated a mild suppression of appetite if caffeine is consumed within four hours of a meal. The cause is unclear, though we can take some guesses. Coffee tends to be a mild gastric irritant - causing some stomach discomfort that may discourage eating. Additionally caffeine tends to aid in the alertness and physical capacity needed for productive work. The result might be that we do not as readily recognize the need to eat because we don’t feel as sluggish.

Do people who drink coffee burn more calories?

Whatever “metabolism boosting” effects coffee has seem to be related to the fact that it makes your body move.

Those who drink coffee every day might notice they engage in more incidental movement under its influence. They may pace, fidget, and tense their muscles more than they otherwise would. These non-exercise moments accumulate significantly throughout the day to increase energy output. Additionally, for those who are exercising regularly, caffeine tends to increases the intensity and duration of exercise by up to 25%. In fact, it is considered by many the athletic world's most potent legal exercise aid.

It is worth noting that many people use caffeine to make up for for lack of sleep. This may be a short term strategy to get through the day, however the increased energy associated with a good night’s sleep will also increase daily energy expenditure or “boost metabolism”. Trading sleep for caffeine is not a good weight management strategy.


Anything else?

One of the most promising health effects of drinking more coffee is the potential for reduction in the risk of Type 2 diabetes, a metabolic disorder in the body’s ability to transport and use blood sugar. A study of over 100,000 men and women who increase their intake of full-caffeine coffee by more than one eight-ounce cup per day over a four-year period found an 11% lower incidence of Type 2 diabetes after another four years, whereas those who decrease their intake by at least one cup showed a 17% increase in diabetes incidence.

This effect might be attributable to weight loss, but might also be related to compounds in coffee that block the toxic accumulation of chemicals contributing to diabetes progression. These cups, by the way, are black or with light milk and sugar, not mocha lattes and caramel cappuccinos.

Diabetic coffee drinkers should know that caffeine is associated with a short-term rise in blood sugar, making diabetes management a greater challenge. The American Diabetes Association still suggests that coffee in moderation is an acceptable part of a healthy diet.

There was a time where drinking coffee was considered to be an unhealthy habit akin to smoking or drinking alcohol. Studies from that era were confounded by the fact that many smokers and alcohol abusers were also consuming the highest amounts of coffee, linking their health outcomes with their coffee consumption. Modern science along with a change in coffee drinking culture has done a better job of disentangling the results of these different habits. It it seeming more and more likely that thoughtful coffee consumption may result in a life-long boon to health.


  1. American Diabetes Association. (2017) What can I drink?

  2. Astrup, A., et. Al. (1990) Caffeine: a double-blind, placebo-controlled study of its thermogenic, metabolic, and cardiovascular effects in healthy volunteers. The American Journal of Clinical Nutrition, 51(5): 759-67.

  3. Bhupathiraju, S.N, et. Al. (2013) Changes in coffee intake and subsequent risk of type 2 diabetes: three large cohorts of US men and women. Diabetologia.

  4. Greenberg, J.A., Boozer, C.N., Geliebter, A. (2006) Coffee, diabetes, and weight control. American Journal of Clinical Nutrition, 84(4): 682-93.

  5. Rustenbeck, I., et. Al., (2014) Effect of chronic coffee consumption on weight gain and glycaemia in a mouse model of obesity and type 2 diabetes. Nutrition & Diabetes ,4(6): e123.

  6. Schubert, M.M., et. Al. (2017) Caffeine, coffee, and appetite control: a review. International Journal of Food Science and Nutrition, 68(8): 901-912.

  7. Van Dam, R. (2015) Ask the expert: coffee and health. Harvard School of Public Health.

  8. Zeratsky, K.(2017) Does caffeine help with weight loss? Mayo Clinic

Health and Coffee Pt. 7: Heart Health

By Julianne Bierwirth, RD


Coffee has a chemical complexity that, through the roasting process, creates a broad range of vibrant flavor characteristics. This same molecular diversity is also responsible for a variety of health effects in humans. Caffeine is certainly the most well-studied, but it is far from the only pharmacologically active molecule extracted during a brew. Some of these chemicals are elusive, and their effects poorly understood. Others, after decades of research, have concrete benefits and detriments firmly borne out by data.

In this 8-part blog series, we delve into the myriad truths, half-truths, and indeed, fallacies, related to the impact that coffee has on your health. Is it good for you? Is it bad for you? Is it going to make your teeth brown? Does coffee make you smarter? Read on to find out.


For years coffee was considered to be bad for health in a variety of ways - heart health chief among them. The caffeine in coffee can raise your blood pressure as part of its work on the sympathetic nervous system. Your adrenaline pumps as part of your flight or flight response and you may even be able to feel your heart racing. If you have high blood pressure or conditions that predispose you to heart problems, drinking coffee may seem the last thing you want to do. Fortunately for enthusiasts coffee isn’t just okay for those with cardiovascular issues, it might soon be prescribed.

Caffeine does raise systolic (top number) blood pressure by up to 10 points, but only in non-habitual drinkers. As the body becomes accustomed to caffeine it adjusts cardiovascular responses to account for the additional boost. If your body didn’t respond this way we wouldn’t see caffeine dependence and withdrawal. By measures other than blood pressure including adrenal response and heart minute volumes (amount of blood pumped per minute by the heart) it seems that coffee has little effect in habitual drinkers.

Research has reliably found no long-term negative cardiovascular effect from drinking coffee, even in those who have cardiovascular disease. But obviously you cannot just drink to your heart's content, pun intended. There is something that stops you after maybe 3 or 6 or 10 cups. It might be the gastrointestinal effect, or an over-excitement that becomes unpleasant and distracting.

However, across years of research, scientists have not been able to define a safe upper limit because data on consumption levels greater than 600 mg caffeine are limited. That is not to say there isn’t a limit. Caffeine’s LD50, or the lethal dose at which 50% of people would die, is considered to be 80-100 cups of coffee as estimated from rat studies done in the course of drug trials. But there is a big gap between 6 cups a day and 80 for which we have basically no scientific understanding.

So if blood pressure and other health measures are not negatively affected in the long run, is coffee just a wash on the cardiovascular front? No. In fact, the research is leaning towards recommending several cups a day for the benefit of heart health and diabetes.

Some of the longest running observational health studies in existence see coffee intake inversely correlated to the risk of cardiovascular disease, heart failure, and stroke. For each additional cup of coffee, a 5-8% decrease in risk factor was seen up to six cups a day. This effect was so pronounced that the USDA, in their 2015 dietary guidelines, suggested that up to five cups of coffee a day can be included in a healthy diet. Additionally, the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure recently lifted the recommendation to restrict coffee and caffeinated beverages.


The big caveat on all of this positive press is how you prepare your coffee. The healthiest for your heart is a black coffee without added milks or sweeteners. Added sugars and saturated fats can quickly negate the beneficial aspects of your morning joe, so go easy and instead find yourself a coffee that is delicious and unique served black. We at 1000 Faces would be glad to help you with that.


  1. Sudano, I. et al. (2005) Cardiovascular effects of coffee: is it a risk factor? Progress in Cardiovascular Nursing, 20(2): 65-9.

  2. Turnbull, D., Rodricks, J.V., Mariano, G.F., Chowdhury, F. (2017) Caffeine and cardiovascular health. Regulatory Toxicology and Pharmacology, 89: 165-85.

  3. Gluckman, T. (2010) Ask an expert: how does caffeine affect the heart? Providence Health & Services. -does-caffeine-affect-the-heart/

  4. Macmillan, A. (2017) Here’s another reason to feel good about drinking coffee. Time.

  5. Mattioni, A.V. (2014) Beverages of daily life: impact of caffeine on atrial fibrillation. Journal of Atrial Fibrillation, 7(2): 1133.

  6. American College of Cardiology (2018) Is caffeine safe, protective for patients with Afib, arrhythmias?

  7. USDA. (2016) 2015-2020 Dietary guidelines: answers to your questions.

Health and Coffee Pt. 6: Coffee and the Brain

By Julianne Bierwirth, RD


Coffee has a chemical complexity that, through the roasting process, creates a broad range of vibrant flavor characteristics. This same molecular diversity is also responsible for a variety of health effects in humans. Caffeine is certainly the most well-studied, but it is far from the only pharmacologically active molecule extracted during a brew. Some of these chemicals are elusive, and their effects poorly understood. Others, after decades of research, have concrete benefits and detriments firmly borne out by data.

In this 8-part blog series, we delve into the myriad truths, half-truths, and indeed, fallacies, related to the impact that coffee has on your health. Is it good for you? Is it bad for you? Is it going to make your teeth brown? Does coffee make you smarter? Read on to find out.


As the neurological effects of caffeine are so potent, those who integrate coffee into their daily lives are best served by understanding how their brain responds to different quantities and timing. Can you drink an afternoon coffee without compromising your sleep? How much is too much for you? What does a day with no coffee feel like?

Understanding the alertness caused by caffeine starts with understanding sleepiness. Sleep is a relatively mysterious topic, even to scientists. You can wake up rested and alert and yet be relatively certain that in sixteen hours you’re going to feel your eyelids drooping again. It certainly seems like there’s a mechanism working away to reconcile the hours you slept with the hours you’ve been awake. The modern theory of sleep surrounds just such a mechanism and a signaling molecule in the brain called adenosine.

As you go about your day adenosine builds up in a section of your brain responsible for what neurologists call “sleep pressure”. More adenosine accumulates over the day, decreasing the speed at which your brain can handle information until a critical level is reached. Melatonin, a sleep hormone, is then released so that you’ll rest and let your body do all of the things it does while sleeping - growing, repairing tissues, and storing memories. As you sleep that adenosine gets cleaned away so that you start fresh the next morning...or not, if you’re not sleeping well enough.


Caffeine and adenosine are very similar chemically- so much so that the body confuses the two. After a coffee the neurons where adenosine builds up get loaded with caffeine temporarily, dampening the signal to the brain. You’re tricked into feeling like you woke up a just an hour or two ago instead of eight or nine hours ago. But when the caffeine goes away the real amount of adenosine is detected and your body gets tired twice as fast.

So how long does the boost last? That depends partly on how much coffee you had. Your liver can process and eliminate half the caffeine in your body in 4-6 hours, meaning that if you had a cup of coffee 5 hours ago about half of that cup’s worth of caffeine is still circulated in your body. 10 hours from now a quarter will still be there, and so on. This is partly why scientists suggest you should abstain from caffeine after 2 PM if you work and sleep relatively normal hours.

What’s primarily important is not getting into a caffeine dependency cycle. If you drink caffeine too late in the day and it affects your sleep you’ll be likely to overuse caffeine the next day to make up for the deficit. The next night’s sleep is unlikely to be great either. It’s a cycle that is unlikely to stop until a long weekend or vacation resets the clock, but you never get back the hours you missed. Caffeine may alleviate the most noticeable effects of poor sleep but the health issues that come with it will create larger problems than a single drowsy day.

Another neurological symptoms frequently associated with coffee is headache. Adenosine reduces blood pressure by opening up blood vessels. When caffeine blocks adenosine the blood pressure goes up, which can alleviate headaches. Frequently headache medicines contain caffeine to boost the efficacy of drugs like acetaminophen. However when the coffee wears off, or if you are a regular drinker and go a day without you might experience the opposite: an unusually low blood pressure and with it withdrawal headaches. Caffeine itself does not induce headaches, only the lack of it will create problems.


On the extreme end of coffee consumption is caffeine intoxication. The symptoms include anxiety, headache, agitation, and overexcitement. As adenosine is suppressed by caffeine the brain speeds up and adrenaline gets released. Adrenaline is responsible for the shakes, excitement, fast speech, and heavy breathing associated with the jitters. You end up feeling like you’re fighting for you life during an everyday meeting or class. The strongest contender for a cure seems to be exercise, which may increase the liver’s processing speed, though the research surrounding this is sparing.

Caffeine is a drug, and like any drug it can be abused. They key is understanding your body’s response and planning your consumption of caffeine accordingly, or else that late night espresso could feel like it haunts you for days.


  1. Bjorness, T. E., Green R. W. (2009) Adenosine and Sleep. Current Neuropharmacology; 7(3): 238-245.

  2. Chawla, J. (2018) Neurologic Effects of Caffeine. Medscape.

  3. Fried, N.T., Elliott, M.B., Oshinsky, M.L. (2017) The role of adenosine signaling in headache: a review. Brain Sciences; 7(3): 30.

  4. Gross, T. (2018) Sleep scientist warns against walking through life ‘in an underslept state’. NPR.

  5. Holst, S. C., Landolt, H-P. (2015) Sleep homeostasis, metabolism, and adenosine. Current Sleep Medicine Reports; 1(1): 27-37.

  6. Lu, S. (2015) Too much coffee?

  7. National Headache Foundation. (2018) Does caffeine trigger or treat headaches.

  8. Urry, E., Landolt, H.P. (2015) Adenosine, caffeine, and performance: from cognitive neuroscience of sleep to sleep pharmacogenetics. Current Topics in Behavioral Science; 25: 331-66.

Golden Bean 2018

As September winds down each year, the team here at the roastery excitedly awaits the results of the Golden Bean North America roasting competition.  This is the Australia-born contest's fourth year in the United States, and it's our third year sending a selection of our coffees off to Portland, Oregon, to be judged across multiple different brewing preparations.  Growing in size once again, the competition filtered through entries from over 500 different roasters - roughly 900 total submissions.  We're proud to announce that we're taking home more medals than ever this year - three in total!

Hilario Sántiz- Silver Medal / Filter Category

Guji Highland - Silver Medal / Filter Category

Duromina - Bronze Medal / Filter Category


Each coffee entry perfectly exemplifies the dedication and hard work of our entire supply chain; and for this, many thanks are in order.  For the Ethiopian coffees (Duromina & Guji Highland), we must thank our importing partners and friends at Trabocca.  They are on the ground in Ethiopia year round, working with cooperatives, washing stations, farm managers, etc, to foster relationships and put outstanding offerings on our cupping table as the seasons pass.  Most notably this year, we must give our deepest gratitude to Jesús Salazar, Hilario Sántiz, and the entire team at Cafeología in Chiapas, Mexico.  It is an honor to be working with a passionate group of producers to show the world what Mexico has to offer.  We're absolutely thrilled that our roast of Hilario Sántiz's coffee ranked among a very short list that was mostly comprised of coffees from Kenya, Ethiopia, and Panama (Gesha).  Lastly, these awards represent our daily hard work here at 1000 Faces - roasting, tasting, tweaking, perfecting - and serve as justification for our roasting and sourcing methodology.  This dedication to the craft and continual pursuit of excellence is what allows us to roast our coffees clearly and cleanly -  transparently displaying the inherent flavor characteristics of each coffee, and thus, the passion and hard work of the producers.  For this, our final tip of the hat goes our Lead Roaster, Ben Bowdoin. 

Unfortunately, some of these coffees are already on their way off of our menu, so you will have to act quick if you're wanting to get your hands on some!  Guji Highland will be depleted through our cafe as early as this weekend.  Hilario Sántiz will be around for 2-3 more weeks.  And finally, Duromina is estimated to last another 1-2 months.  If you do miss out, no need to fret!  Lots of stunning fresh crop coffees are lined up.  Very soon we will be releasing our next natural Ethiopia of the season, Dimtu Tero, and it happens to be from the same area as the Guji Highland.  Furthermore, we have three more Mexico offerings and two more washed Ethiopia offerings that we will cycle onto the menu throughout the year - so stay tuned!  

Health and Coffee Pt. 5: Coffee and Cancer

By Julianne Bierwirth, RD


Coffee has a chemical complexity that, through the roasting process, creates a broad range of vibrant flavor characteristics. This same molecular diversity is also responsible for a variety of health effects in humans. Caffeine is certainly the most well-studied, but it is far from the only pharmacologically active molecule extracted during a brew. Some of these chemicals are elusive, and their effects poorly understood. Others, after decades of research, have concrete benefits and detriments firmly borne out by data.

In this 8-part blog series, we delve into the myriad truths, half-truths, and indeed, fallacies, related to the impact that coffee has on your health. Is it good for you? Is it bad for you? Is it going to make your teeth brown? Does coffee make you smarter? Read on to find out.


In March of this year a California judge ruled that coffee sellers and coffee products in the state must warn customers that the beverage contains a chemical known to cause cancer. This ruling prompted a wave of confusion and concern that spread well beyond California’s borders. We at 1000 Faces fielded lots of questions along the lines of, ‘wait, isn’t coffee supposed to be good for you?’. According to the US government it is; the most recent USDA Dietary Guidelines for Americans recommended drinking coffee, up to 5 cups a day, for its role in reducing the risk of diabetes and heart disease.

The lawsuit resulting in the March ruling contended that coffee contains a chemical called acrylamide, a byproduct of the roasting process, and that acrylamide is a known carcinogen. It is true that coffee contains acrylamide and some public health organizations do classify it as a carcinogen. And yet the vast body of coffee research shows that, on the whole, moderate coffee drinkers are healthier, live longer, and have reduced incidence of things like diabetes, heart disease, and even cancer. This decision in California has been highly confusing to the public, so in addition to discussing the role of coffee in preventing many kinds of cancer, this article will define carcinogens and put acrylamide into perspective.

Carcinogens are substances that mutate a cell’s DNA in a way that signals that cell to go into a cycle of unchecked replication. We encounter countless types and qualities of carcinogens every day. Let’s take as an example the sun and its role in skin cancer. Sunlight is made of photons which are basically particles of energy. That energy can interact with the earth in many ways; initiating reactions that drive photosynthesis in plants, heating the planet, and causing our skin to form Vitamin D. Incidentally, the energy in these photons can also cause mutations to the the DNA of your skin cells.

Some people will sunbathe for years and never get cancer because, by sheer luck, their DNA never gets damaged in a way that causes cancer. Some people will never spend a moment in a bathing suit and will develop cancer because of their sun exposure walking to and from work. What we know is that the more sun exposure you get the more chance that sunlight has to cause the unlikely but devastating cancerous mutation. Sunlight is carcinogenic, and the odds of getting cancer from sunlight are directly proportional to the amount of sunlight you absorb.

Carcinogens as a whole are like this: they cause DNA damage and the more you are exposed to them the more often you are gambling with that damage being carcinogenic. There is a linear relationship: lower exposure equals lower risk, higher exposure equals higher risk. Logically, that means that any chemical that causes cancer, at any dose, is considered a carcinogen.


In practice the research looks like this: a mouse will be fed a chemical at a very high dose, say about 1000 times more than would naturally occur in its diet. If that mouse gets cancer more often than the control mice and this happens consistently enough study after study, then the chemical gets classified as a carcinogen. Unfortunately this means that the list of carcinogens expands rapidly to anything that can, at any unreasonable dosage, cause cancer. By this definition a great many things are carcinogens.

It is important to know that some chemicals are more carcinogenic than others - which is to say that a lower dose more often results in cancer. Aflatoxin, a chemical produced by a grain-loving mold in certain climates, is one of the most carcinogenic substances known to man. Parts of coastal China that are endemic for the growth of this mold have people and animals diagnosed with liver cancer at extraordinary rates. Mouse studies done with aflatoxin show that it takes a very low dose to cause cancer. Mouse studies done with acrylamide, however show that it takes an astronomical dose to cause cancer.

Acrylamide is formed inside the coffee beans when they are roasted above 250 degrees Fahrenheit. Its formation is the chemical result of starch and protein interacting at high temperatures - it is not added to the beans, nor is it a function of the brewing process. Coffee is not the only culprit - French fries and potato chips have the largest concentrations of acrylamide in our diets. It isn’t currently possible to roast coffee in a way that prevents the formation of acrylamide or to remove the acrylamide once the coffee is roasted. Unlike sunlight, acrylamide seems to offer no health benefit - only a potential health detriment.

Still, acrylamide, causes cancer in mice only at extremely high doses. An average sized human would have to drink the equivalent of about 2.6 million cups of coffee a day to get the 200 milligrams per kilogram body weight of acrylamide that has been shown to cause cancer in mice according to one study. In some research the results don’t even show an effect in mice at all. That isn’t to say there isn’t a risk, there possibly is, but acrylamide is certainly not a potent carcinogen like Aflatoxin. Some organizations, including the World Health Organization (WHO) do not classify it as a carcinogen at all. The American Cancer Society says they aren’t sure that acrylamide affects the risk of cancer in humans.

There are many chemical properties of the coffee we drink that seem to confer a benefit, including ones that decrease the incidence of cancer. These do not usually act by slowing cancer progression or repairing DNA damage, though there exist some molecules in nature that can work on that level. These antioxidants instead act to neutralize some carcinogens before they have a chance to damage your DNA.


In 2016, Nature, one of the most reputable scientific journals, published a statistical overview of 105 published studies on coffee and different types of cancer. Their analysis found increase in coffee consumption correlated with an increased risk for lung cancer but a reduced risk of oral, pharynx, liver, colon, prostate, endometrial cancer and melanoma. A 2017 review on coffee and cancer similarly concludes that there is, if anything, a mild benefit to drinking coffee.

In the light of these positive results it is worth stating that the vast majority of research looking at cancer risk takes the form of prospective studies. This means that researchers don’t assign individuals to groups of coffee drinkers and coffee abstainers and wait to see who forms cancer. This kind of trial would be both very expensive and take many years. Instead, they study the coffee drinking habits of people who develop cancer compared to those that don’t. There may be many other confounding variables that influence both coffee consumption and cancer risk, such as smoking status or ethnicity. The studies that exist aren’t perfect, but they are extremely encouraging.

So why did this California lawsuit move forward? The Council for Education and Research on Toxins (CERT), a public health advocacy group, sued the coffee industry seemingly as part of a larger effort to reduce the concentration of acrylamide in the American diet. CERT did the same years ago with potato products, suing fast-food companies over labeling on French fries. However, the law firm that represented CERT, Metzger Law Group, shares a mailing address with the advocacy group, driving curiosity as to the intentions of the suit. The ruling meant a substantial amount of money for the legal team involved. We’re not saying there’s a conflict of interest, but there’s a strong chance there’s a conflict of interest here.

In this case. the burden of proof was on coffee sellers to prove that acrylamide in coffee posed no significant risk. By the technical definition of a carcinogen and in accordance with California’s Proposition 65 - The Safe Drinking Water and Toxic Enforcement Act of 1986, the coffee industry was always going to have a rough go of defending themselves against this legal challenge. Some are suggesting that CERT and the Metzger Law Group are abusing the intention of Prop 65 for their financial gain and diluting its importance in clear and honest public health communication.

If nothing else, this ruling focuses very narrowly on one chemical component of the coffee, failing to take into account the health effects of coffee as a whole. No public health official would recommend abstaining from all sun exposure for fear of skin cancer. Years of research and thousands of studies have shown that, on the whole, coffee has a positive impact on health and longevity. Even if acrylamide causes cancer at very high doses, this is definitely a case of failing to see the forest for the trees.

Authors Note: as a scientist and dietitian, the Prop 65 decision in California as it relates to coffee is personally frustrating to me. Communicating scientific information to the public in a balanced and nuanced way is already very challenging. It is also the most important role of a scientist. When organizations, governments, or entities muddy the waters further by making claims that are factually true but irrelevant to the larger picture it confuses the public so that they no longer know which messages about health and safety are accurate and important. Some warning labels resulting from the 1986 Prop 65 decision convey a genuine and significant risk. If the label stays up for coffee and individuals (in my opinion) rightfully disregard it, that disregard may extend to all Prop 65 warnings, weakening its power as a public health communication tool.



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  2. Cha, A.E. Good news: it’s totally fine to drink lots (and lots) of coffee. The government just said so. The Washington Post. 2016. https:// new-u-s-dietary-guidelines-say-you-can-have-up-to-5-cups-a-day/? noredirect=on

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  4. Ingber, S. Calif. judge rules coffee must come with a warning label. But should it? NPR. 2018. 2018/03/30/598348764/fact-check-calif-judge-rules-coffee-must-come- with-a-cancer-warning-but-should-i

  5. Lantz, I., Ternite, R., Wilkins, J., Hoenicke, K., Guenher, H., van der Stegen, G.H. Studies on acrylamide levels in roasting, storage and brewing of coffee. Mol Nutr Food Res. 2006; 50(11): 1039-46.

  6. Salzburg, S. Coffee causes cancer. Coffee prevents cancer. Wait, what? Forbes. 2018. coffee-causes-cancer-coffee-prevents-cancer-wait-what/ #5240370615ee

  7. US Food and Drug Administration. Survey data on acrylamide in food: individual food products. 2016. foodborneillnesscontaminants/chemicalcontaminants/ucm053549.htm

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