Blueberries, bilberries, blackcurrants, cranberries and strawberries are rich in flavonoid compounds (eg anthocyanins, flavonols, phenolic acids, ellagitannins and proanthocyanidins). Regular consumption of these plant-based phytochemicals are associated in observational studies with a reduction in the risk of type 2 diabetes and death from cardiovascular disease. In animal studies, blueberries have been shown to improve mental performance and even reverse some degree of memory impairment.
Black Elderberry (Sambucus nigra), a fruit-bearing shrub native to Europe and North America, has long been researched for its immune boosting potential. Elderberry is unusually rich in anthocyanins, a class of flavonoids that may protect cells against damage or infections. Clinical and experimental studies suggest elderberry fruit extract is particularly useful against viral influenza.