Cardiovascular diseases (CVDs) are a major cause of premature deaths and are linked to several health conditions and habits such as smoking, high cholesterol, obesity, hypertension, unhealthy diet, and diabetes. The American Heart Association proposed the Ideal Cardiovascular Health (ICVH) score in 2010, which assesses seven parameters including healthy behaviors (BMI, diet, physical activity, and non-smoking) and favorable health factors (normal blood sugar, cholesterol, and blood pressure).
The Mediterranean diet (MedDiet), which is rich in healthy fats, antioxidants, and bioactive molecules, has been shown to reduce the risk of CVDs. It includes a high intake of nuts, legumes, fruits, vegetables, extra virgin olive oil and more.
Although polyphenols, which improve cardiovascular health, are present in the MedDiet, their availability in the small intestine is low. Most of the polyphenols reach the large intestine, where they undergo enzymatic reactions catalyzed by the gut microbiome, leading to the formation of microbial phenolic metabolites (MPM). Although limited studies have evaluated the benefits of MPM on cardiovascular health, they have potential biological functions.
The Research Details: A recent Food Research International study has investigated the association between microbial phenolic metabolites (MPM) and adherence to the Mediterranean diet (MedDiet) on cardiovascular health in an elderly Mediterranean population. Based on a subpopulation of the PREDIMED trial, it conducted a five-year clinical trial that examined the effect of the traditional MedDiet on the prevention of cardiovascular diseases (CVDs).
The experiment included 200 randomly selected participants from the PREDIMED - Hospital Clinic recruitment center in Barcelona, Spain. The researchers used a linear ion trap quadrupole-Orbitrap-mass spectrometer (LTQ-OrbitrapMS) for the analysis, which provided accurate structural information to detect and quantify novel metabolic compounds.
The present sub-study of the PREDIMED trial explored the relationship between Mediterranean Diet (MedDiet) adherence, phenolic metabolites and cardiovascular health. The results showed that higher urinary phenolic metabolites (MPM) scores were associated with greater adherence to the MedDiet and improved cardiovascular health metrics. A robust inverse relationship was found between the urinary concentrations of urolithin B glucuronide (UBG) and low-density lipoprotein (LDL)-cholesterol.
The study also found that greater adherence to the MedDiet is linked to changes in the gut microbiome and an increase in Bacteroidetes genus Prevotella, which are involved in polyphenol metabolism. Despite the association between MPM and MedDiet adherence, individual MPM was not found to have a significant impact on overall cardiovascular health. The results suggest that multiple phenolic metabolites appear to positively benefit cardiovascular health, rather than individually.
Strengths and Limitations of the Study: The current study has several strengths, including the use of biological samples for analysis, providing robust data on individual metabolism. The use of LTQ-Orbitrap technology also allowed for precise identification and quantification of metabolites. However, the study has some limitations. The participants were only elderly Mediterranean individuals at high risk of developing cardiovascular diseases, limiting the generalizability of the findings. Additionally, the lack of fecal samples prevented the authors from determining the participants' gut microbiota composition.
Summary: This study is a pioneering effort in exploring the relationship between urinary phenolic metabolites (MPM), diet, and cardiovascular health through the use of the LTQ-OrbitrapMS technique. The results show a strong connection between higher urinary MPM levels, greater adherence to the Mediterranean Diet (MedDiet), and improved cardiovascular health. The phenolic metabolites related to the MedDiet appear to have a positive impact on cardiovascular health. Further research is necessary to fully comprehend the influence of phenolic compounds in biological samples on overall cardiovascular health.