Abstract
Many environmental stresses cause an increase in reactive oxygen species in plants and alter their nutritional value. Plants respond to many stresses by producing increased amounts of compounds with antioxidant properties including vitamins, phenylpropanoids and carotenoids. Such compounds have wide-ranging health-promoting effects in humans that are partly due to their antioxidant function because oxidative stress underlies many human diseases. Some of these compounds have complex interactions with the gut, promoting gut health and changing the gut microbiome, whereas the gut influences the bioavailability of the ingested compounds and may metabolize them into products with different effects on health than the original compound. Substantial efforts have been made to increase the nutritional value of crops through breeding or transgenic approaches, but comparatively little effort has been directed towards increasing nutritional value through crop management and environment, which may present another approach to enhance the nutritional quality.