Calorie restriction improves pretty much every established measure of health and slows pretty much every established measure of aging in a wide range of species, our own included. If people cared more about longevity, then everyone would be a calorie restriction practitioner - no presently available medical technology can do as much for a basically healthy individual as simply eating less while still obtaining all necessary micronutrients. As it is, however, only a comparatively small number of people seem able to evaluate future benefits to health and life expectancy as being more rewarding than the consumption of additional calories here and now. Which is too bad, but that's the human condition for you.
Research into the biochemical mechanisms of calorie restriction, its relationship with our variable metabolism, and the way in which variations in metabolism determine natural longevity all continues apace. There has been a steady stream of new discoveries over the past ten years, a growing catalog of specific ways in which ingesting fewer calories improves the operating biology of a range of species. Here is an interesting new addition to that list:
Flies on the low-calorie diet showed a 100 percent increase in the release of brain chemicals, which are called neurotransmitters, from their neurons. These chemicals carry signals from one nerve cell to another across gaps called synapses. The brain has millions of synapses that are believed to be the critical structures required for normal brain function. Diseases such as Parkinson's harm them irreparably.
Furthermore the chemicals were secreted at critical locations. "Diet restriction increased the neurotransmitters released at synapses called neuromuscular junctions," Dr. Eaton said. "These synapses, which form on muscle, transmit nerve impulses from the brain to muscles, resulting in movement. If neuromuscular junctions degenerate, resulting in the release of less neurotransmitter, then muscle activity diminishes. This is observed in diseases such as myasthenia gravis and amyotrophic lateral sclerosis (ALS)."
The observation that diet could directly affect the amount of neurotransmitter secreted by the neuron was a novel observation that had not been seen previously. "People have seen that diet has effects on the nervous system, but the nuts and bolts of what it is doing to neurons have not been established," Dr. Eaton said. "We believe we have shown a novel and important effect."
It remains to be seen how this will translate into mammals - there doesn't appear to be a great deal of literature out there on calorie restriction and neurotransmitters, and what does exist may or may not be particularly relevant to this finding, as it seems to largely focus on the brain itself rather than its connections to other bodily systems. There are a lot of different neurotransmitters, and a lot of locations in the nervous system where they can behave in different ways or produce different results.