Evidence began mounting as long as 70 years ago that restricting calories while consuming necessary amounts of sustenance could increase one’s life span. Since then, a group called the North Carolina-based Calorie Restriction Society has sprouted whose 1,800 members routinely down about half of the daily caloric intake recommended by the Food and Drug Administration (FDA) in the hope of living to the ripe old age of 120.
New research may prompt the organization to send out nose plugs with its next newsletter.A team of scientists at the Baylor College of Medicine in Houston, found that the average life span of fruit flies on restricted diets decreased when they were exposed to food odors.
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Biosingularity 
its methionine restriction that provides the calorie restriction benefit. my theory is that the metabolism of methionine produces homocysteine which is a powerful oxidant which in turn damages the mitochondria among other things…i think you see where im going.
folate,b12,and tmg will decrease methionine levels.