I received the following email from Dr. Jonny Bowden. Of  course, it was followed by trying to sell a supplement. Here's the email that I promptly deleted.

The miracle anti-aging nutrient for your brain

Glycerophosphocholine (GPC) is a supplement that has been extensively researched for its effect on mental performance, attention, concentration and memory formation. Like Phosphatidylserine (PS), it’s a member of the class of biochemicals known as phospholipids, which are so important in making healthy cell membranes. GPC is found in abundant quantities in mother’s milk, which ought to tell us something about it’s importance in human life. There are only tiny amounts in food, so to get the full therapeutic value of this wonderful substance, supplements are the way to go.

A large body of scientific research has demonstrated GPC’s importance for the brain. My friend, the biochemist Parris Kidd, PhD, an internationally known expert on nutritional supplements, says "I continue to be fascinated by GPC’s capacities to salvage function in the damaged brain, to sharpen mental performance even in people who are healthy, and to give new vitality to the aging brain".