EAT FOR HEALTH Australian Dietary Guidelines

EAT FOR HEALTH – AusTRALiAn diETARy guidELinEs

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Guideline 2

The following studies relate primarily to whole fruit, although some included dried fruit and/or fruit juice in their

definitions of fruit intake. The evidence regarding fruit juice and excess weight is included under drinks in Section

3.3.2. Although serve sizes differed between studies, the evidence statements presented below are based on

standard serve sizes of 150g.

Cardiovascular disease, type 2 diabetes and excess weight

•   Cardiovascular disease: It is probable that consumption of each additional daily serve of fruit is associated

with a reduced risk of coronary heart disease (Grade B; Evidence Report, Section 1.1).362-364 Increased protection

of at least 7% was gained from each additional serve of fruit consumed per day. It is probable that consuming

at least one and a half serves of fruit a day, ideally two and a half or more, is associated with a reduced risk of

stroke (Grade B; Evidence Report, Section 1.2).368,369

•   Type 2 diabetes: The recent evidence suggests that consumption of fruit is not associated with risk of type 2

diabetes (Grade C; Evidence Report, Section 1.4). However, as there is a strong relationship between type 2

diabetes and body weight (see Chapter 1), the association between consumption of fruit and reduced risk of

excess weight gain (see below) suggests longer-term studies may be required to investigate potential effects.

•   Excess weight: The recent body of evidence suggests that consumption of fruit is associated with a reduced

risk of obesity and weight gain (Grade C; Evidence Report, Section 1.3).200-208

Cancer

•   Alimentary tract cancer: There is emerging evidence that fruit consumption is associated with reduced risk

of several types of cancer along the alimentary tract. The recent body of evidence suggests that consumption

of fruit is associated with a reduced risk of oral and nasopharyngeal cancer (Grade C; Evidence Report, Section

1.10),373,374,376,377,402 consistent with findings of a convincing effect on reduced risk of cancers of the mouth, pharynx

and larynx and a limited effect on nasopharyngeal cancers described in the WCRF report (see Appendix F).^43

•   Breast cancer, ovarian cancer and endometrial cancer: Expanding on previous reports,^36 recent evidence

now suggests that consumption of fruit is not associated with risk of breast cancer (Grade C; Evidence Report,

Section 1.6),378,403-407 ovarian cancer (Grade C; Evidence Report, Section 1.11)384,385 or endometrial cancer (Grade

C; Evidence Report, Section 1.12).386-388,408

•   Colorectal cancer: Recent evidence suggests that consumption of fruit is not associated with risk of colorectal

cancer (Grade C; Evidence Report, Section 1.8).378,389,402,407,409-411 Further, there is limited evidence to suggest an

association between the consumption of most fruits by specific type and colorectal cancer (Evidence Report,

Section 1.14),389,411 which expands on earlier studies by the WCRF (see Appendix F).^43

•   Other cancers: Recent evidence is limited and/or inconclusive for an association regarding fruit consumption

and gastric, lung, oesophageal and pancreatic cancers (Evidence Report, Sections 1.5, 1.7, 1.9 and 1.13).

2.2.5 How consuming plenty of vegetables, including different types and colours,

and legumes/beans, and fruit may improve health outcomes

Various mechanisms may explain the different health benefits of diets high in vegetables, legumes/beans and

fruit. These include potential synergies between the foods as well as the action of specific components found

at high levels in these foods, including vitamins and minerals, various phytochemicals including carotenoids and

bioflavonoids (such as anthocyanins and flavonols), as well as dietary fibre and other specific characteristics of

these foods such as low energy (kilojoules) density.

Cardiovascular disease, type 2 diabetes and excess weight mechanisms

Food components with anti-oxidant activity including vitamins (vitamin C and E) and phytochemicals in these

foods may reduce the risk of inflammation and haemostasis, and of cholesterol becoming oxidised and deposited

in blood vessels to form the atherogenic plaques that underlie many cardiovascular conditions.392,412-414 Several

studies have shown that consumption of vitamin C is associated with reduced risk of cardiovascular disease and

stroke, however, other studies have shown no protective effect.8,415 Plant foods including vegetables and fruit

provide potassium and magnesium, both of which have been linked to lower blood pressure.^8 Importantly, reviews

of the effect of beta-carotene on coronary heart disease suggest that benefits may be related to the components

of the foods, various antioxidants and micronutrients in these foods or other confounding factors, rather than to

the beta-carotene alone.^416