“Coffee is typically considered a harmful addiction, even though many studies have confirmed its health benefits. Moderate coffee consumption (maximum 400 mg of caffeine per day, equivalent to 3-4 cups) can reduce the risk of diabetes, cardiovascular disease, certain types of cancer, and Parkinson’s disease, among other things,” explains Adrienn Szabó, dietitian at the Semmelweis University Outpatient Clinic. The health benefits are primarily due to the antioxidant compounds found in coffee, i.e., the plant’s active ingredients. Coffee beans are very high in carbohydrates, but they also contain fats, proteins, minerals, and vitamins. Caffeine plays a role in disease prevention, but the positive health effects are also present in decaffeinated coffee, adds the expert.
Many fear that drinking coffee on an empty stomach causes reflux and irritation of the stomach lining, or possibly an increase in stress hormones (cortisol). However, coffee contains important antioxidants, such as chlorogenic acid and ferulic acid, which have anti-inflammatory effects, so it is not prohibited to drink coffee even if you have inflammatory bowel disease, provided that the condition is in remission. Since obesity, smoking, alcohol consumption, and extreme stress greatly increase stomach damage and reflux, caffeine can intensify these symptoms in people who suffer from these conditions. On the other hand, coffee on an empty stomach does not harm healthy people, the expert points out.
Another misconception is that coffee causes high blood pressure. For those struggling with hypertension, my first piece of advice as a dietitian would be to reduce salt intake, exercise, and eat more vegetables, fruits, legumes, and oilseeds instead of quitting coffee altogether.
The dietitian adds that this refers to moderate coffee consumption (1-2 cups per day) and is just general advice, as there are always exceptions and individual cases, and caffeine metabolism varies greatly from person to person.
If someone drinks large amounts of coffee, i.e. more than four cups a day, and has been diagnosed with high LDL cholesterol levels, then the consumption of coffee may be a factor to consider in their diet. This is because unfiltered black coffee – e.g., Turkish coffee, French press, moka pot, or espresso – contains plant compounds (cafestol, kahweol) that can raise LDL cholesterol levels by reducing the production of bile acids, which play an important role in fat metabolism. However, with moderate coffee consumption, this is unlikely to be a concern, notes Adrienn Szabó.
The dietitian emphasizes that in the case of filter-brewed coffees (e.g., V60, batch brew, AeroPress, etc.), the amount of this compound – which is particularly beneficial in certain respects – is much lower, so people who drink a lot of coffee should opt for this type.
She adds that coffee roast intensity is also an important factor. “When coffee is roasted, the heat activates a reaction between the proteins and carbohydrates in the coffee beans. This process, which causes changes in color and flavor, is known as the Maillard reaction. This turns the light green coffee beans into a darker hue of brown. The same thing happens when making toast. Melanoidin, a beneficial antioxidant, is also a by-product of this reaction. However, the darker the coffee beans are roasted (at higher temperatures and for longer periods of time), the more harmful, carcinogenic compounds are released, and the health benefits of coffee are reduced. So, from a dietary point of view, we should favor light roast coffee,” she advises.
Not many people know that instant coffee is simply brewed black coffee that was freeze-dried. During the process, the liquid is gradually cooled, and its moisture is extracted, so when instant coffee is dissolved in water, it contains the same amount of caffeine, although its flavor is slightly weaker and its antioxidant level is somewhat lower than that of freshly brewed black coffee.
Most consumers are aware of coffee’s diuretic effect, which is especially noticeable when a large amount is consumed. It is also worth noting that since caffeine is a water-soluble compound, if we brew it with more water, it will contain more caffeine, thus increasing its diuretic effect. It is therefore advisable to drink water after coffee. However, the small glass of sparkling water served alongside black coffee in cafés is not intended for rehydration. If we drink this before coffee to cleanse our palate, we can taste the aroma of our cup of coffee more clearly, says the expert.
The health benefits of coffee are, of course, most effective when consumed plain, without sugar or milk. In this case, it even has an anti-caries effect thanks to an active ingredient that prevents bacteria (Streptococcus mutans) from adhering to the teeth.
Adrienn Szabó also draws attention to another important aspect: From a calorie intake perspective, it is better to drink coffee black. If we drink it with lots of milk or plant-based milk, and sugar, we should bear in mind that a single cup of latte can contain as many calories as an adult’s afternoon snack.
Orsolya Dávid
Translation: Judit Szabados-Dőtsch
Photo by Attila Kleb; cover (illustration): iStock.com/iWichy
Sources:
Han, M., Oh, Y., & Myung, S. K. (2022). Coffee Intake and Risk of Hypertension: A Meta-Analysis of Cohort Studies. Journal of Korean medical science, 37(45), e332. https://doi.org/10.3346/jkms.2022.37.e332
Ren, Y., Wang, C., Xu, J., & Wang, S. (2019). Cafestol and Kahweol: A Review on Their Bioactivities and Pharmacological Properties. International journal of molecular sciences, 20(17), 4238. https://doi.org/10.3390/ijms20174238
Mendoza, M. F., Sulague, R. M., Posas-Mendoza, T., & Lavie, C. J. (2023). Impact of Coffee Consumption on Cardiovascular Health. Ochsner journal, 23(2), 152–158. https://doi.org/10.31486/toj.22.0073
Godavarthy, D., Naik, R., Gali, P. K., Ahmed Mujib, B. R., & Baddam, V. R. R. (2020). Can coffee combat caries? An in vitro study. Journal of oral and maxillofacial pathology : JOMFP, 24(1), 64–67. https://doi.org/10.4103/jomfp.JOMFP_172_19
