Coffee drinkers around the world cheered when research study after research study proved that drinking coffee in moderation could provide a range of health benefits; including: preventing cancers, preventing stroke, preventing diabetes, preventing cardiovascular disease, preventing depression, preventing antibiotic-resistant bacterial infections, preventing cirrhosis of the liver, preventing gout, preventing gallstones, and preventing Parkinson’s and Alzheimer’s disease. It can even reduce muscle soreness after a workout! There are studies that show that you are plain old less likely to die (from any cause) if you are a coffee drinker! 1 This implies that drinking coffee every day can actually extend your life! (This Wikipedia page has links to some of the many science articles showing coffee is beneficial). In the paleo community, these health benefits are often cited to rationalize our addictions (coffee contains mild psychotropics) to this delightful beverage (what I generally think of as “comfort in a cup”). Let us all raise our mugs of hot delicious americanos (whipped with coconut oil) in toast!
Er, not so fast. Coffee is made from a seed (not a legume, but the pit of the coffee fruit). Right away this should put us on the alert since seeds tend to contain protective compounds to prevent digestion and thereby ensure the survival of the plant species. In the case of wheat, those compounds cause increased intestinal permeability (i.e., leaky gut) and prime the immune system to exaggerate inflammation and potentially cause autoantibody formation, which is clearly detrimental to our health. In the case of the itty bitty seeds in blueberries, those compounds have such a low toxicity level as to have a negligible effect on our health (and the beneficial antioxidants and polyphenols in blueberries more than compensate!). So, where on that spectrum is the coffee bean?
Coffee is very rich in antioxidants and polyphenols. Many of the health benefits of coffee are attributed to these substances. These chemicals are also found abundantly in fruits and vegetables, which is why a diet rich in plant matter has pretty much the same list of health benefits as coffee (well, actually, far more health benefits). Some of the health benefits of coffee are directly attributable to its caffeine content (which is also why drinking tea which is rich in antioxidants, polyphenols and also contains caffeine is also associated with good health). This is partly why many of the beneficial effects of coffee are not seen with decaf coffee. Also, the decaffeination process tends to strip the coffee not only of much of its caffeine content but also many of its antioxidants and polyphenols (potentially leaving behind a few of the more harmful substances that can be found in coffee).
A large percentage of people report that coffee upsets their stomach or gives them heartburn. This is because coffee stimulates the secretion of the main gastric hormone gastrin 2. This causes excessive secretion of gastric acid and speeds up gastric peristalsis (even decaf coffee has this effect). Coffee also stimulates release of the hormone cholecystokinin (CKK), which stimulates release of bile from the gallbladder. In a healthy individual, this release of bile salts is likely sufficient to neutralize the highly acidic chyme. However, deficiencies in gall bladder function are associated with metabolic syndrome 3. In the case of reduced gall bladder function or excessive coffee consumption, highly acidic chyme travels through the small intestine where it irritates and inflames the lining of the intestines. This is also clearly a good argument for consuming coffee with food.
One of the detrimental effects of consuming caffeine (whether from coffee, tea, chocolate or energy drinks) is the effect that it has on cortisol. Caffeine acts to increase cortisol secretion by elevating production of adrenocorticotropic hormone by the pituitary gland 4. Excessive cortisol production can lead to a variety of health issues, including an overactive immune system, disrupted sleep, impaired digestion, and depression. When you consume caffeine, your cortisol level increases (dependent on what your cortisol management is like to begin with and how much caffeine you consume) and can stay elevated for up to 6 hours. With daily consumption, your body will adapt somewhat and not produce quite as much cortisol, but complete tolerance to caffeine does not occur 5. Very importantly, if you are a habitual consumer of caffeine, your cortisol will increase more dramatically in response to stress (like that guy cutting you off in traffic) than someone who doesn’t consume caffeine 6,7. If you have difficult managing stress as it is, caffeine is not helpful to you.
One key study showed that moderate coffee consumption in healthyindividuals correlated with increased markers of inflammation in their blood 8. People who drank more than 200mL (that’s one large cup in my house) of coffee every day (equivalent to 37.3mg of caffeine) had increased circulating white blood cells and several key inflammatory cytokines (chemical messengers of inflammation, usually restricted to the site of injury or infection). When cytokines circulate in the blood, they cause low level inflammation everywhere in the body. This chronic systemic inflammation is exactly one of the situations we are trying to prevent with adoption of a paleo diet! These increases in markers of inflammation were persistent even after adjusting for other health and lifestyle factors (such as age, sex, weight, exercise, and smoking).
If you have celiac disease or gluten sensitivity, extra caution should be used when consuming coffee. Internal data from Cyrex Labs shows that for people who produce IgG or IgA antibodies against gluten (i.e., gluten sensitivity), coffee is the most common cross-reactive food. This is because there is a high degree of homology between some coffee proteins and gluten (this means the proteins look very similar so if your body is producing antibodies against gluten, they are more likely to also recognize coffee proteins). Food sensitivities are one of the main issues that prevents the body from fully healing after adopting a paleo diet. If your health isn’t improving as dramatically as you expected after adopting a paleo diet and if you are gluten-sensitive, continuing to consume coffee may be the culprit.
So, should you drink coffee or not? Are you tired of hearing me say “it depends”? It does depend. If you are very healthy, have lost most of the weight you need to lose, have regulated your hormones and healed your gut, coffee (in moderation) is likely to provide you a health benefit (Yay!). This benefit is likely comparable to drinking tea and/or consuming diet rich in vegetable matter (I’m trying to say that if you don’t like coffee, don’t go out of your way to drink it). However, in people just starting their paleo journey, especially people with evidence of metabolic derangement, giving up coffee for at least a little while will likely speed up the healing process (D’Oh!). Also, caffeine in general is contraindicated for those with adrenal fatigue. Those people with autoimmune diseases should take special care with consumption of coffee as their systems are particular sensitive to irritants and they have a much higher likelihood of an immune response to coffee (because they have a much higher likelihood of gluten intolerance and food sensitivities in general). Overall, coffee gets the “proceed with caution” label.