In March 2019 researchers from China and Norway published the results of their study to assess the association between coffee consumption and levels of certain metabolic and inflammatory biomarkers. A total of 15,551 women and 7,397 men with no history of diabetes, cardiovascular disease, or cancer were involved in the study. Detailed dietary information was collected from each individual. The following biomarkers were then assessed following a blood test: C-peptide, insulin-like growth factor 1 (IGF-1), IGF binding protein 1, IGF binding protein 3, estrone, total and free oestradiol, total and free testosterone, sex hormone-binding globulin (SHBG), total adiponectin, high-molecular-weight adiponectin, leptin, C-reactive protein (CRP), interleukin 6, and soluble tumor necrosis factor receptor 2. Results showed that compared with non-coffee drinkers, individuals who drank 4+ cups/day had lower levels of C-peptide, IGF binding protein 3, estrone, total oestradiol, free oestradiol, leptin, C-reactive protein, interleukin 6, and soluble tumor necrosis factor receptor 2 plus higher levels of sex hormone-binding globulin, total testosterone, total adiponectin and high-molecular-weight adiponectin. The results were similar for both caffeinated and decaffeinated coffee. The researchers therefore concluded that coffee consumption was associated with favourable metabolic and inflammatory biomarkers.
Hang D et al. Coffee consumption and plasma biomarkers of metabolic and inflammatory pathways in US health professionals. Am J Clin Nutr. 2019 Mar 1;109(3):635-647