The Spanish Study
At the European Society of Cardiology, ESC Congress 1 last weekend, Spanish researchers working as part of the long term project Seguimiento Universidad de Navarra (SUN) Project, presented their new study that suggests coffee intake might be tied to a longer life. The study included around 20,000 Spanish participants.
This was primarily an observational study. Dr Adela Navarro, a cardiologist at Hospital de Navarra, Pamplona, Spain explained that coffee is one of the most commonly used beverages in the world and there have been studies that have shown that consuming coffee reduces the risk of death due disease.
This study however was the first one to look at populations in a Mediterranean country. The study was part of the Seguimiento Universidad de Navarra (SUN) Project, a long-term prospective cohort study which means that a group of participants and their health parameters and features were looked at for a period of years of follow up.
The risk of death among middle aged Spanish population and their coffee consuming habits were assessed. The participants were university graduates when they were enrolled for the study in 1999. Finally at the end of the study, only around 19 896 participants remained for analysis. The average age of these participants was around 37.7 years. Each of the participants were provided with a semi-quantitative food frequency questionnaire at the beginning of the study. This was done to collect information regarding how much coffee they consumed, their lifestyle, their social characteristics, health conditions and measurements of their vital statistics etc. These participants were then followed up for a period of average 10 years.
During this time the information about the deaths and cause of death of any of the participants was gathered from the families, postal officials or the National Death Index. Statistical tests were used to assess the risk of deaths and its association with the coffee consumption habits. Other factors that could influence the results called the confounders, were eliminated from the analysis to come to a robust conclusion from the study results.
Study results revealed that during the period of the study over the decade, 337 patients died. It was noted that those who took at least four cups of coffee per day had a 64% lower risk of death due to any cause compared to those to never or almost never drink coffee. For every two additional cups of coffee, the risk of death due to all causes fell by 22 percent. Deaths may be influenced by numerous factors. This includes gender of the patient, his or her age and also adherence to the Mediterranean diet. Mediterranean diet has been shown to reduce the risk of death due to heart disease in numerous large and long term studies.
Researchers found that coffee consumption was significantly different in different age groups. Persons who were around 45 years old for example, when drank two extra cups of coffee ended up reducing their risk of death by 30 percent. This was not seen among younger participants of the study. Dr. Navarro explained that this association or benefit could be due to the fact that coffee was more protective among older participants than among the younger ones. Navarro advised that “drinking four cups of coffee each day can be part of a healthy diet in healthy people.”
The Broad Study
A larger study with 521,330 participants from 10 different European countries was reported this month in the Annals of Internal Medicine. This study too examined the effects of coffee consumption on all-cause deaths and cause-specific deaths. This was part of the EPIC (European Prospective Investigation into Cancer and Nutrition) study.
Over an average of 16.4 years of follow up of the participants, 41,693 deaths occurred. Here too, results showed that risk of deaths reduced with increased coffee consumption. Risk of diseases of the digestive system were also lower with coffee intake in both men and women participants.
Risk of diseases of the circulatory system and cerebrovascular system also were lower with coffee consumption among women.
Risk of ovarian cancer however showed a skewed pattern with being more associated with increased coffee consumption. Increased coffee intake was also associated with lower levels of liver enzymes such as serum alkaline phosphatase; alanine aminotransferase; aspartate aminotransferase; γ-glutamyltransferase.
Rise in these enzymes are a marker of liver disease. Among women, increased coffee intake led to lowered C-reactive protein, lipoprotein(a), and glycated hemoglobin levels.
The first of these is a marker for inflammation (C-reactive protein) while the latter two are markers of high cholesterol and diabetes respectively. Results of this study remained consistent throughout the 10 European countries studied.
The study was funded by the European Commission Directorate-General for Health and Consumers and International Agency for Research on Cancer.