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Appendix J Studies examining the health effects of intake of fruit and
vegetables together
The literature includes studies that have investigated the effect of consumption of fruit and vegetables together.
This evidence clearly confirms the positive health effects of consuming vegetables and fruits, particularly in
reducing the risk of cardiovascular disease, but also in reducing risk of obesity and some cancers. It is compiled
as an Appendix to aid the conciseness of Chapter 2.
Cardiovascular disease, type 2 diabetes and excess weight
There is evidence regarding a probable association between the consumption of each additional daily serve of fruit
and vegetables and reduced risk of coronary heart disease (Grade B; Evidence Report, Section 3.1).362-364,367,1105
Similarly, recent evidence supports a probable association between consumption of each additional daily serve of
fruit and vegetables and a reduced risk of stroke (Grade B; Evidence Report, Section 3.2).362,363 Consuming more
than five serves of fruit and vegetables a day was found to reduce the risk of stroke by 26% (fruit serve was 80g and
vegetables 77 g),^363 and consuming each additional serve of fruit and vegetables (of average serve size 106 g) reduced
the risk of stroke by 5%.^362 These results are consistent with those presented in the literature reviews to inform the
recent review of the Dietary Guidelines for Americans, 2010 which found that ‘consistent evidence suggests at least
a moderate inverse relationship between vegetable and fruit consumption with myocardial infarction and stroke, with
significantly larger, positive effects noted above five serves of vegetables and fruits per day’.^198
In the literature reviews to inform the revision of the Dietary Guidelines for Americans, 2010, the evidence for an
association between increased fruit and vegetable intake and reduced risk of excess body weight was found to be
modest, with a trend towards decreased weight gain over five or more years in middle adulthood associated with
increased fruit and vegetable intake. However no conclusions could be drawn from the evidence of efficacy of
increased fruit and vegetable consumption in weight loss diets.^198 In children and adolescents, the limited body of
evidence from longitudinal studies suggested that greater intakes of fruits and/or vegetables may protect against
increased adiposity.^198
Cancer
Lung cancer: The recent body of evidence suggests that consumption of fruit and vegetables is associated with
reduced risk of lung cancer (Grade C; Evidence Report, Section 3.5).1106-1108
Colorectal cancer: Recent evidence suggests that there is no association between consumption of fruit and
vegetables together and risk of colorectal cancer (Grade C; Evidence Report, Section 3.4).389,410 In its 2008 report,
the International Agency for Research on Cancer (IARC) also concluded that intakes of fruit and vegetables were
either not associated or only slightly associated with risk of colorectal, breast and prostate cancer.110 9 However,
recently published findings from the European Prospective Investigation into Cancer and Nutrition (EPIC) study
suggest that a high consumption of fruit and vegetables is associated with reduced risk of colorectal cancer,
especially of colon cancer, but that the effect may also depend on smoking status.^1110
Ovarian cancer: It is probable that there is no association between consumption of fruit and vegetables and
risk of ovarian cancer (Grade B; Evidence Report, Section 3.6).384,385 A more recent meta-analysis has described
evidence of a probable inverse relationship between consumption of vegetables and fruit, and bladder cancer.^1111
An insufficient number of studies were found to produce an evidence statement for an association between the
consumption of fruit and vegetables and renal cancer.1112 - 1114
Epithelial cancer: In general, comparison of the results of systematic reviews of the evidence on diet and cancer
sponsored by the WCRF in 1997^1115 and 2007^43 suggests weaker evidence of a protective effect of high intakes
of fruits and vegetables against several common epithelial cancers, with a downgrading of the association from
‘convincing’ to ‘probable’. This is also consistent with the evidence presented in the IARC report.^1116
Overall cancer: Analyses of prospective studies have generally failed to demonstrate consistent evidence of a
convincing association between the intake of fruits and vegetables and overall risk of cancers.110 9 However the
more recent EPIC cohort study found a weak but statistically significant inverse association between consumption
of fruit and vegetables and risk of overall cancers – a 4% lower incidence of all cancers combined for an increment
of 200g total fruit and vegetable intake per day.^1117