Dietary and nutritional supplements including those containing silk fibroin; dietary beverage supplements for human consumption in liquid and dry mix form for therapeutic purposes; dietary food supplements; dietary supplemental drinks; dietary and nutritional supplements for supporting brain health, enhancing memory and concentration, improving cognitive health and preventing cognitive decline, and protecting neuronal cells; health food supplements; nutritional supplements in the form of tablets, capsules, caplets, chewables, powder, syrups, gummies, and gels; powdered nutritional supplement drink mix and concentrate