Background: Increasing vegetable intake and diversity are recommended to maintain good health. The benefits of increasing vegetable intake are well established. However, evidence for vegetable diversity is scarce.
Aim: To investigate the associations of vegetable diversity with atherosclerotic vascular disease (ASVD) mortality and subclinical measures of atherosclerosis in a cohort of elderly Australian women.
Methods: Vegetable diversity was assessed within a validated food frequency questionnaire using a single question, ‘How many different vegetables do you usually consume each day (<1 to ≥6 per day)’. Cox proportional hazards modelling was used to assess the association between vegetable diversity and ASVD mortality in 1,226 women aged ≥70 years without clinical ASVD or diabetes mellitus at baseline (1998). In 2001, high-resolution B-mode carotid ultrasonography was used to measure common carotid artery intima-media thickness (CCA-IMT) (n=954) and carotid plaque severity (n=968). Subclinical measures of atherosclerosis were analysed using linear and logistic regression.
Results: Over 15 years (15,947 person-years) of follow-up, 238 ASVD-related deaths were recorded. Vegetable diversity (number/d) was inversely associated with ASVD mortality (multivariable-adjusted HR=0.83, 95%CI=0.78, 0.93, P=0.001). Women consuming ≥5 different vegetables per day had 4.8% lower mean CCA-IMT (P=0.003) and 5.1% lower maximum CCA-IMT (P=0.001) compared to women consuming <3 different vegetables per day. No associations were observed between vegetable diversity and carotid plaque severity (P>0.05).
Conclusions: These data identify a potential benefit of increasing vegetable diversity among elderly women for ASVD risk reduction. Further studies are needed to replicate these findings in older men and younger cohorts.