EAT FOR HEALTH Australian Dietary Guidelines

EAT FOR HEALTH – AusTRALiAn diETARy guidELinEs

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Guideline 2

•   Prostate cancer: The evidence suggests that consumption of one to two serves of tomatoes a day is

associated with reduced risk of prostate cancer (Grade C; Evidence Report, Section 2.13).382,383 This is

consistent with the probable relationship between intake of lycopene-containing foods and probable reduced

risk of prostate cancer described by the WCRF report (see Appendix F).^43

•   Endometrial, ovarian and pancreatic cancer: The 2003 edition of the dietary guidelines reported a possible

reduction in risk of endometrial and pancreatic cancer with vegetable consumption.^36 However, in more recent

studies there is no evidence to suggest an association between total vegetable consumption and ovarian

(Grade C; Evidence Report, Section 2.11)384,385 or endometrial cancer (Grade C; Evidence Report, Section

2.12).386-388 However, findings from the WCRF report suggest decreased risk of both ovarian and endometrial

cancer with consumption of non-starchy vegetables specifically (see Appendix F).^43

•   Colorectal cancer: The evidence suggests no association between consumption of green leafy, cruciferous

vegetables, or carrots, potatoes, beans or lentils and risk of colorectal cancer (Grade C; Evidence Report,

Section 2.15).^389 More specific studies suggest that consumption of more than one serve per week of spinach

is associated with reduced risk of colorectal cancer (Grade C; Evidence Report, Section 2.15)^389 and evidence

of a suggestive protective effect of intake of non-starchy vegetables on colorectal cancer has been described in

the WCRF report (see Appendix F).^43

•   Lung cancer: Recent evidence^390 suggests consuming cruciferous vegetables is associated with reduced

risk of lung cancer (Grade C; Evidence Report, Section 2.14). The WCRF report found evidence of a probable

association with the reduced risk of lung cancer and consumption of vegetables containing carotenoids and

also found evidence suggesting that non-starchy vegetables were protective of lung cancer (see Appendix F).^43

This supports the notion that different types of vegetables may have different effects which may help to explain

conflicting results seen when all vegetables are grouped together in varying proportions in different studies.

•   Other cancers: Recent evidence is limited and/or inconclusive for the association regarding other types of

vegetable consumption and gastric, breast, lung and colorectal cancers (Evidence Report, Sections 2.5, 2.6,

2.7 and 2.8).

Other conditions

The 2003 edition of the dietary guidelines included evidence of associations between the consumption of

vegetables and some aspects of eye health, including cataracts and macular degeneration.^36 Further evidence

was not available from more recent studies.^391

2.2.3 The evidence for consuming ‘plenty of legumes/beans’

While evidence of the health benefits of consumption of legumes/beans appears to have strengthened since the

2003 edition of the dietary guidelines, the recent research is dominated by studies into the health benefits of soy

foods and products rather than investigations into legumes per se.^1

Table 2.3: Evidence statements for consuming ‘plenty of legumes/beans’

Evidence statement Grade

Consumption of soy foods is associated with reduced total cholesterol and low-density lipoprotein (LDL) cholesterol. C

Consumption of legume foods is associated with reduced risk of colorectal cancer. C

Notes: Grades — A: convincing association, B: probable association, C: suggestive association

Includes evidence statements and gradings from the Evidence Report (literature from years 2002–2009). Does not include evidence from

other sources, such as the 2003 edition of the dietary guidelines (in which individual studies were classified according to their design as

level I, II or III but overall grades for relationships were not derived), although these sources have been used to inform these Guidelines.

Grade C evidence statements showing no association and all Grade D statements can be found in Appendix E.

Recent evidence confirms a protective effect for consumption of legumes, and particularly soy foods, against

several risk factors and diseases. However more research is needed to determine the quantities of legume/beans

1 The evidence presented here was reviewed with a focus on whole foods, and for this reason studies of soy isolates

are not reported.