Health benefits of apples: epidemiological evidence

Cardiovascular disease

A reduced risk of cardiovascular disease has been associated with apple consumption. The Women's Health Study surveyed nearly 40,000 women with a 6.9-year follow-up, and examined the association between flavonoids and cardiovascular disease [23]. Women ingesting the highest amounts of flavonoids had a 35% reduction in risk of cardiovascular events. Flavonoid intake was not associated with risk of stroke, myocardial infarction, or cardiovascular disease death. Quercetin did not have any association with cardiovascular disease, cardiovascular events, myocardial infarction or stroke. However, both apple intake and broccoli intake were associated with reductions in the risk of both cardiovascular disease and cardiovascular events. Women ingesting apples had a 13–22% decrease in cardiovascular disease risk.In a Finnish study examining flavonoid intake and coronary mortality, it was found that total flavonoid intake was significantly inversely associated with coronary mortality in women, but not in men [24]. Apple and onion intake was also inversely associated with coronary mortality, especially in women. Data collected from this same cohort study also showed the effect of quercetin and apple intake on cerebrovascular disease [25]. Those who had the highest consumption of apples had a lower risk of thrombotic stroke compared to those who consumed the lowest amounts of apples [25]. Onion intake and quercetin intake were not associated with thrombotic stroke or other cerebrovascular diseases.Apple and wine consumption was also inversely associated with death from coronary heart disease in postmenopausal women in a study of nearly 35,000 women in Iowa [26]. The intakes of catechin and epicatechin, both constituents of apples, were strongly inversely associated with coronary heart disease death. Although total catechin intake was inversely associated with coronary heart disease mortality, Arts et al (2001) found that tea catechins were not associated with coronary heart disease mortality in postmenopausal women. Apple catechins may be more bioavailable than the catechin and epicatechin gallates commonly found in teas.

The relationship between flavonoids and risk of coronary heart disease were also examined as part of the Zutphen Elderly Study [14]. Flavonoid intake was strongly correlated with a decreased mortality from heart disease in elderly men and also negatively correlated with myocardial infarction. Tea was the main source of flavonoids in this study and was also negatively correlated with coronary heart disease. Apple intake contributed to approximately 10% of the total ingested flavonoids and was also associated with a reduced risk of death from coronary heart disease in men, however the relationship was not statistically significant [14].