Fruits are glucose in the human body and the human brain uses only glucose to function.
Glucose is the main fuel for the brain. Because neurons cannot store glucose, they depend on the bloodstream to deliver constant supply of glucose. So, this is very important for the brain activity.
The level of glucose in our blood is very important as too much of it at a time can actually make our brain lose glucose. As the level of glucose in the blood stream increases, the brain depletes its energy supply, influencing our abilities to remember, learn and concentrate.
Is good to remember that mental activity requires a lot of energy as our brain cells need two times more energy than any other cells in our bodies.
Neurons main activities are related to repairing and rebuilding worn out structural components, manufacturing enzymes and neurotransmitters that have to be transported using nerve “channels” (some of them can be several inches or even several feet long).
Still, the upper mentioned activities are not the ones using most of neurons’ energy. The most demanding ones are the bioelectric signals, used for communicating throughout the nervous system. These transmissions are so demanding that use half all brain’s energy (almost 10% of all body’s energy).
In an important study, Dr. Carol Greenwood from the University of Toronto tested the effects of glucose on older adults. Two groups of old adults were tested. The first group received a bowl of cereal and milk, along with white grapes juice for breakfast, while the other group received only water.
When tested 20 minutes later, the first group had a better memory as they were able to remember 25% more facts as compared to the second group.
Additionally, Rondall J. Kaplan stated that “eating carbohydrate food can improve memory within an hour after ingestion in healthy elderly people with relatively poor memories. Individuals with seemingly minor deficits in glucose regulation appear to perform worse on cognitive (memory) tests and are most sensitive to the beneficial effects of carbohydrates”.
Additionally, Paul Gold, PhD, and Donna Karol, PhD, of Binghamton University, and Carol Manning, PhD, of the University of Virginia, stated in the American Journal of Clinical Nutrition that glucose particularly improves people’s adeptness at tasks involving memory and attention.