Eating less could make you live longer and healthier. Italian scientists published research in Proceedings of the National Academy of Sciences which showed that calorie-restriction triggered a protein molecule, CREB1, that activates a group of genes linked to longevity and good brain function.
CREB1 (CAMP Responsive Element Binding Protein 1) is a protein involved in regulating important brain functions such as long-term memory, learning and anxiety control. Protein kinases migrate to the cell's nucleus where it activates CREB, leading to the formation of long-term memories and long-term potentiation. In 1995 at Cold Spring Harbor Laboratory, Jerry Yin and Tim Tully examined the CREB1 protein in fruit flies and found that an overproduction of this protein led the flies to develop a photographic memory. How cool is that!
These studies were done feeding mice only 70% of what they would normally consume, which equivocates to eating about 600 less calories per day for humans (I guess this would depend on geographical location, sex, age, etc. of the individual).
It was also found that caffeine helped to boost CREB1 production, so might be a better idea to have a cup of coffee instead of dessert after your meal.