Should the results of this study determine what kind of coffee one drinks? Does it really make a difference? Eh...Not for me (because all coffee seems to be beneficial), but it might for you.
Studies show that daily drinking of coffee appears to have health benefits. Studies have linked coffee consumption with lower rates of cancer (here and here), cardiovascular disease, and diabetes. Coffee contains beneficial chemicals (such as caffeine and chlorogenic acid) that are antioxidant and anti-inflammatory, and could help fight chronic inflammatory diseases. It turns out that how much coffee beans are roasted changes how much chlorogenic acid they contain, but the amount of caffeine basically stays the same among the different roasting levels.
Researchers in Korea compared the caffeine and chlorogenic acid components of Arabica coffee beans at different roasting levels: Light, Medium, City, and French roast. They then tested various protective antioxidant and anti-inflammatory properties of the different coffee extracts in various "cell models" (meaning in the lab, not on real people). They found that chlorogenic acid levels were higher in light roasted coffee extract than the other roasted groups, and also light roasted coffee extract had the highest antioxidant activity. The results found that increasing degrees of roasting reduced antioxidant and anti-inflammatory activities.
From the Journal of Medicinal Food: Cellular Antioxidant and Anti-Inflammatory Effects of Coffee Extracts with Different Roasting Levels
During roasting, major changes occur in the composition and physiological effects of coffee beans. In this study, in vitro antioxidant effects and anti-inflammatory effects of Coffea arabica green coffee extracts were investigated at different roasting levels corresponding to Light, Medium, City, and French roast. Total caffeine did not show huge difference according to roasting level, but total chlorogenic acid contents were higher in light roasted coffee extract than other roasted groups. In addition, light roasted coffee extract had the highest antioxidant activity.... The expression of mRNA for tumor necrosis factor-alpha and interleukin-6 was decreased in cells treated with the coffee extracts and the expression decreased with increasing roasting levels. These data suggest that coffee has physiological antioxidant and anti-inflammatory activities and these effects are negatively correlated with roasting levels in the cell models.
Coffee is one of the most popular beverages worldwide. Increasing consumption of coffee is related to the pleasing taste and aroma, as well as its physiological effects. Coffee is proposed to exert beneficial effects against cancer, cardiovascular disease, obesity, and diabetes. Coffee contains phenolic compounds such as caffeic acid, chlorogenic acid, ferulic acid, vanillic acid, and other phytochemicals. The quality of coffee is significantly related to the roasting process.... During roasting, there are numerous changes in coffee bean compound profiles and the aroma is increased. Major changes in coffee bean composition occur during roasting as a result of the Maillard reaction..... Roasting markedly affects chlorogenic acid, leading to hydrolysis of chlorogenic acid. New compounds are formed during the roasting process; one of these is melanoidin. Its formation might alter the overall antioxidant capacity of coffee beans after roasting.
Coffee is a rich source of antioxidants that may contribute to prevention of oxidative stress-related diseases. The antioxidant properties of coffee may reflect the presence of both phenolic and nonphenolic bioactive compounds, such as caffeine and chlorogenic acids. Previous studies have shown that coffee has protective effects against oxidation and DNA damage in human cell models and has been shown to possess an in vitro antioxidant activity that lessens lipid peroxidation and neoplastic activity.
Caffeine is the major component in coffee extract and has antioxidant property. Chlorogenic acid is another well-known efficient antioxidant in coffee extract; it was highest in Light roast coffee extract and highest with low roasting temperature and lowest in Dark roasted extract. Carbohydrates, protein, and chlorogenic acid are all decreased in coffee during the roasting process.... Caffeine contents showed no differences among roasting levels, but chlorogenic acid content decreased as roasting degree increased..... The effect of coffee roasting on the antioxidant properties of coffee extracts was investigated in several earlier studies; antioxidant capacity decreased in Dark roast coffee. The antioxidant property of coffee extracts prepared with different roasting levels was also determined in this study. The best antioxidant activity was evident in Light roast coffee extract and the lowest in French roast coffee.