The grain’s purplish brown colour comes from the high quotient of anthocyanins, plant flavonoid pigments, commonly referred to as bioflavonoids, which are responsible for the purple tone in grapes, berries and other dark coloured fruits.
Studies indicate that the antioxidant capacities of anthocyanin pigments may provide protection from DNA damage and oestrogen dependant cancers, as well as boosting production of immune regulating cytokines, and strengthening blood capillaries and cell membranes.
In addition to anthocyanins, purple wheat grain also contains the lignan SDG (secoisolariciresinol diglucoside), an antioxidant phytoestrogen also present in linseed, sunflower and pumpkin seeds. Some of the grain’s purplish colour is achieved by the presence of melatonin, which controls our circadian rhythms and is also an antioxidant with particular role in the protection of nuclear and mitochondrial DNA.
Researchers consider that the presence of SDG and melatonin, in addition to anthocyanins, may be a major reason why the various health benefits listed above are associated with eating coloured cereal grains.