Cruciferous vegetables intake & health benefits
There is significant evidence that increasing consumption of fruit and vegetables is of benefit for maintaining health and preventing a host of diseases. But are all fruit and vegetables equal? Cruciferous vegetables, which include amongst others broccoli, cauliflower, cabbages, bok choy, kale, watercress, turnip and rocket, seem to be particularly standing out. Three summary reports in this issue are reporting epidemiological observational studies, which show a significant inverse association between consumption of cruciferous vegetables and all-cause mortality (Mori et al.), lung cancer risk (Zhang et al.) and hardening of arteries (Blekkenhorst et al.). Interestingly, these studies report observations from different geographical locations, with notably different types of cruciferous vegetables consumed (for example, Asian populations are predominantly consuming Chinese cabbages, whereas US, Australian and European populations are predominantly consuming broccoli and cauliflower).
This suggests that despite the varied structural diversity of the glucosinolates, the sulfur compounds that are unique to cruciferous vegetables, they all share common mechanistic pathways that prevent disease. Once consumed, glucosinolates are converted into bioactive isothiocyanates, which have been shown to have anti-inflammatory, anti-oxidant, and chemopreventive properties, in animal and cell models. The time is now right to support such observational evidence for the health benefits of cruciferous vegetables with robust experimental clinical studies in humans, in order to determine whether glucosinolates are alone responsible for the benefits, or other sulfur metabolites found in these vegetables are also beneficial.