A new American Journal of Clinical Nutrition article has studied the effect of flavonoid intake on the incidence of coronary heart diseases (CHD). The results have shown an inverse correlation between the intake of certain type of flavonoids and incidence of coronary heart disease while there was no significant relationship between total flavonoid intake and incident CHDs.
It is now proven that a dietary regimen containing fried foods, high fat, and high sugar is strongly correlated with an increased risk of mortality and morbidity arising from cardiovascular events. These food regimens are found to be more common in African American people and in the southern United States, an area which is called “Stroke Belt”. In contrast, studies have shown that in people who consume more vegetables and fruits, there are significantly reduced cardiovascular events. A part of this protective effect of fruits and vegetables can be attributed to their flavonoids.
Flavonoids are proactive, polyphenolic compounds found in a wide variety of plant-based foods, including fruit and vegetables (like parsley, thyme, etc.) tea, wine, nuts, herbs, and spices. Flavonoids have been shown to have a wide variety of biological effects in in-vitro (laboratory settings) studies, including anti-inflammatory, anti-microbial, anti-fungal, antiviral, antioxidant and anti- cancer activities.
Since previous studies had limited study populations, this cohort study which is published in the American Journal of Clinical Nutrition, has addressed the effects of the flavonoid-containing foods on the incidence of coronary heart disease in a geographically and racially diverse US population.
This cohort has studied the data from 16,678 African-American and Caucasian people, the study population was selected from the 30,239 participants of REGARDS (Reasons for Geographic and Racial Differences in Stroke) study. The dietary assessment was done using the Block 98 food frequency questionnaire (FFQ, a 107-item questionnaire developed by Nutrition Quest and has been validated in populations relevant to the REGARDS study) and the flavonoid intake from foods was analyzed with The USDA Database for the Proanthocyanidin Content of Selected Foods and the USDA Provisional Flavonoid Addendum to the USDA Food and Nutrient Database for Dietary Studies (FNDDS), version 4.1.
All the patients were without CHD at baseline, the study cohort was followed up for a total time of 6 years and the correlation between the flavonoid intake and incidence of coronary heart disease was determined using proper analytic methods.
The findings showed that the high flavonoid intake was associated with the Caucasian race, exercise, not smoking, higher educational level, and higher income. There was a significantly lower risk of CHD among participants who were including anthocyanidins and proanthocyanidin-rich flavonoids in their dietary habits, while there was no meaningful correlation between total flavonoids and other subclasses of flavonoids with coronary heart disease incidence.
In conclusion, the authors have stated that higher reported intakes of anthocyanidins and proanthocyanidins (both are subclasses of flavonoids) were associated with a lower risk of incident CHD after adjustment for demographic, socioeconomic, health behavior, and dietary factors. Similarly, higher reported intakes of apples and pears, berries, and wine were also inversely associated with incident CHD.
Written By: Nima Makhdami, M.D.