[Fruits] are not only nutritious, but they are also medicinal in their properties. They produce certain beneficial changes in the blood (which medical men term "alterative"), which alters the blood from an unhealthy to its healthy condition; consequently, by the use of ripe fruits, many diseases lurking in the system are either neutralized or removed. Many fruits have the peculiar medicinal property of "cooling" the blood as it is termed, or in other words, rendering it less liable to feverish or inflammable excitement.Though not supported by any kind of serious scientific fact, it turns out these notions were right on the money. What Grandma (and mid 19th-century docs) took on faith has since been borne out by research. In the past 15 years or so, fruits (especially those with deep colors) have been identified as being exceptionally concentrated sources of antioxidants, with effects ranging from memory improvement to tumor suppression.
So, next time you eat some blueberries, just see if your inflammable excitement doesn't abate.