Fruits, vegetables and heart diseases, increased risk of mortality and atherosclerosis
Intake of fruits, berries and vegetables may reduce cardiovascular disease risk through the beneficial combination of antioxidants, fiber, potassium, magnesium and other phytochemicals. Since dietary recommendations concern the intake of whole foods instead of nutrients, the effects of these constituents might be best evaluated by investigating the intake of fruits and vegetables. Furthermore, confirmation of the associations between foods and disease risk will help and simplify advice for heart healthy diet. A report by Ness and Powles reviewed findings from studies that focused directly on fruit and vegetable intake rather than on nutrient intakes in association with CVD. The findings support a protective role for fruits and vegetables in CVD, although the results were inconsistent.
A look into the KIHD data
In KIHD Study we first studied the association of the dietary intake of fruits, berries and vegetables with all-cause, CVD-related and non-CVD-related mortality. The subjects were Finnish men aged 42-60 years examined in 1984-89. Dietary intakes were assessed by 4-d food intake record during the baseline phase of the KIHD Study. The risk of all-cause and non-CVD-related deaths was studied in 2641 men and the risk of CVD-related death in 1950 men who had no history of CVD at baseline. During an average follow-up time of 13 years cardiovascular as well as non-cardiovascular and all-cause mortality were significantly lower among men with the highest consumption of fruits, berries and vegetable (highest fifth, >400 g/day). After adjustment for the major CVD risk factors, the relative risk for men in the highest fifth of fruit, berry and vegetable intake for all-cause death, CVD-related and non-CVD-related death was 0.66 (confidence interval 0.50-0.88), 0.59 (0.33-1.06), and 0.68 (0.46-1.00), respectively, compared with men in the lowest fifth.
We have also studied the association of the dietary intake of fruits, berries and vegetables with early atherosclerosis, manifested as increased intima-media thickness of the common carotid artery wall (CCA-IMT). The subjects were 1380 men examined in the prospective KIHD Study and classified into quarters according to the dietary intake of fruits, berries and vegetables. The mean daily intake of fruits, berries and vegetables was 285 g. In a covariance analysis adjusting for major CVD risk factors (age, systolic blood pressure, serum LDL cholesterol and triglycerides, maximal oxygen uptake, BMI and urinary excretion of nicotine metabolites), intake of total energy and saturated fat, and technical covariates (ultrasound observer and examination years), men in the lowest quarter of dietary intake had a significant increment in both the mean CCA IMT and the maximal CCA IMT (P=0.004 and P=0.002 for difference, respectively) as compared to the other men. The increments of the mean and maximal CCA-IMT were linear across quarters of intake of fruits, berries and vegetables (0.81, 0.79, 0.77, 0.77 mm and 1.02, 0.99, 0.97, 0.96 mm, respectively) (adjusted P for linear trend 0.004 and 0.008, respectively). Adjusted mean and maximal CCA-IMTs among men without previous history of coronary heart disease were 0.79, 0.77, 0.75, 0.75 mm and 0.99, 0.97, 0.94, 0.94 mm, respectively (adjusted P for the lowest quarter versus other quarters 0.014 and 0.013, respectively) (adjusted P for linear trend 0.023 and 0.024, respectively).
These data show that a high fruit, berry and vegetable intake is associated with significantly reduced risk of mortality and IMT thickness in middle-aged Finnish men. Consequently, the findings of this work indicate that diet dominated by plant-derived foods can promote longevity and good cardiovascular health. These studies are part of Tiina's doctoral thesis.
More information: tiina.rissanen at uef.fi, sari.voutilainen at uef.fi
Sari Voutilainen, Jaakko Mursu, Tarja Nurmi, Tiina Rissanen. Carotenoids and cardiovascular health. Am J Clin Nutr 2006;83:1265-71.
Rissanen TH, Voutilainen S, Virtanen JK, Venho B, Vanharanta M, Mursu J, Salonen JT. Intake of fruits, berries and vegetables and mortality: the Kuopio Ischaemic Heart Disease Risk Factor (KIHD) Study. Journal of Nutrition 2003;133:199-204.
The most popular Finnish vegetable: sausage