A new study shows that people who eat a diet that includes at least half a serving per day of foods high in flavonoids like strawberries, oranges, peppers and apples may have a 20% lower risk of cognitive decline. The research is published in the July 28, 2021, online issue of Neurology. The study looked at several types of flavonoids, and found that flavones and anthocyanins may have the most protective effect.