The Role of Folate, Antioxidant Vitamins and other Constituents in Fruit and Vegetables in the Prevention of Cardiovascular Disease: The Epidemiological Evidence

Abstract

Evidence that fruit and vegetables may protect against coronary heart disease is accumulating. It is unclear which constituents of fruit and vegetables are responsible for this protective effect. Folate as a co-substrate in homocysteine metabolism may be important. An intake of about 400 micrograms folate equivalents/day seems to be required to achieve stable low homocysteine blood levels. Five of eight epidemiologic studies show significant inverse associations between folate and cardiovascular disease. These associations could be confounded by antioxidant vitamins and/or other substances. In trials examining an association between folate and cardiovascular disease such confounding must be excluded, before specific recommendations can be given. Observational studies suggest that vitamin C plays a role in the aetiology of cardiovascular disease, but there are no completed intervention trials of this vitamin alone. With regard to vitamin E two cohort studies point to cardiovascular benefits with the long-term use of supplements of at least 100 IU/day, but the results of controlled trials are inconclusive. There is some evidence from observational studies of an inverse association between beta-carotene and cardiovascular disease, particularly in smokers. Intervention trials do not support this hypothesis, rather, they suggest a possible harmful effect of beta-carotene supplements in smokers. Nevertheless, protective effects of beta-carotene and vitamin E in different dosages, durations of administration, or different combinations are still possible. The last paragraph of this review discusses limitations of the present and priorities of future research.

Variety in fruit and vegetable consumption and 10-year incidence of CHD and stroke

“…Fruit and vegetables are rich sources of micronutrients and bioactive phytochemicals that may play an important role in the prevention of CHD and stroke and are relatively low in energy density (28) . We found that more variety in fruit and vegetables was associated with higher intakes of vitamin C, carotenoids, flavonoids and dietary fibre.…”

Multiple Models for Rosaceae Genomics

“…Some strawberry cultivars have the highest concentrations of L-ascorbic acid among all fruits (Haffner and Vestrheim, 1997). Other phenolic compounds belonging to distinct chemical classes, many of which are also potential antioxidants and anticancer agents (Eichholzer et al, 2001;Schieber et al, 2001), have been isolated from rosaceous fruits (Macheix et al, 1991).…”

DNA damage in children and adolescents with cardiovascular disease risk factors

“…The intake of antioxidant vitamins not as supplements, but within a healthy diet, reduces CVD risks (Eichholzer et al 2001, Obrenovich et al 2011. Despite controversies, there is evidence that antioxidant vitamins may inhibit LDL oxidation to its more atherogenic form, therefore preserving the inhibition of atherosclerotic plaque formation ASSOCIATION BETWEEN CARDIOVASCULAR RISk FACTORS AND DNA DAMAGE (Wattanapitayakul and Bauer 2001).…”