Higher intakes of anthocyanins and flavanones are associated with a lower risk of myocardial infarct
Earlier studies have shown that dietary fruit and berry intake may reduce cardiovascular disease risk. However, more studies are needed to find out that which fruits and berries are most beneficial, and which key constituents are responsible for the health benefits. Recent studies have suggested beneficial effects of higher intakes of specific fruits, including blueberries and grapes, for reducing the risk of type 2 diabetes. Furthermore, flavonoids seem to be improving endothelian function, blood pressure and insulin sensitivity. Therefore, flavonoids might be key constituents of fruits and berries that decrease the risk of cardiovascular disease. Most of the studies that have examined the associations between flavonoids and cardiovascular disease have focused on women. Thus, this study was concentrating on men.
Altogether 43 880 men (aged 32-81) were enrolled in a 24 y of follow-up study. Each participant returned a questionnaire on lifestyle factors biennially. Furthermore, every 4 y participants completed food-frequency questionnaires. Participants who reported a history of cardiovascular diseases or cancer were excluded. During the follow-up, the incidence of myocardial infarction and stroke among the participants was calculated. The individual intakes of flavanones and anthocyanins were derived. The association between myocardial infarction and stroke risk and flavonoids was analysed by using left-truncated Cox proportional hazards regression models. Many factors were controlled, such as BMI, physical activity, smoking, alcohol consumption and smoking.
Figure 1. The anthocyanin content of wild bilberry is 300-700 mg/100 g.
During 24 y of follow-up, 4 046 cases of myocardial infarctions and 1 572 cases of stroke were reported. Men with higher flavonoid intake smoked less, exercised more and had a lower intake of saturated fat, energy, and alcohol and higher cereal fibre intake. Higher anthocyanin intake was associated with a 14% lower risk of nonfatal myocardial infarction. Furthermore, flavanone intake was associated with a 22% lower risk of ischemic stroke, with the greatest magnitude in participants aged ≥65 y. Anthocyanins and flavanones are commonly consumed through fruit intake because they are present in either red or blue fruits and berries (anthocyanins) or citrus fruits (flavanones) (Table 1). Therefore, a simple dietary change has the potential to have a considerable population-level impact on cardiovascular disease prevention in men.
Table 1.Common sources of anthocyanins and flavanones. Wild forest bilberry (Vaccinium myrtillus) is not mentioned in the table. However, the anthocyanin content of bilberry is 300-700 mg/100 g. It contains anthocyanins at a level that is 3-5 higher than that in highbush blueberry. Table has been redrawn from: Cassidy et al. (2016): Habitual intake of anthocyanins and flavanones and risk of cardiovascular disease in men. American Journal of Clinical Nutrition doi: 10.3945/ajcn.116.133132.
1 cup = 225 g, 1 oz = 28 g
The reasons for different associations of anthocyanins and flavanones with cardiovascular disease are unclear. Of all the flavonoid subclasses, flavanones are one of the best absorbed and most effective at crossing the blood-brain barrier, inhibiting platelet function, and decreasing plaque progression. This might explain the association of flavanones with ischemic stroke. Anthocyanins may be inversely associated with non-fatal myocardial infarction risk through mechanisms related to improvements in cholesterol efflux capacity or a reduced susceptibility of the myocardium to ischemia or reperfusion injury.
Source: Cassidy, A., Bertoia, M., Chiuve, S., Flint, A., Forman, J. & Rimm E. (2016): Habitual intake of anthocyanins and flavanones and risk of cardiovascular disease in men. American Journal of Clinical Nutrition doi: 10.3945/ajcn.116.133132.
flavonoidit antosyaanit flavanonit sydän- ja verisuonitaudit sydäninfarkti aivohalvaus miehet flavonoids anthocyanins flavanones heart disease stroke men