Antioxidants or Fermenting Gut Flora?

Long life is the result of a good diet and exercise. Plant antioxidants are eaten to sop up the reactive oxygen species (ROS) and omega-3 fatty acid-rich fish oils are consumed to reduce the production of inflammatory prostaglandins. Avoiding inflammation that has been linked to essentially all degenerative and autoimmune diseases should make us live better and longer. Unfortunately it is more complex than that, and studies in the simple nematode, Caenorhabditis elegans, show that your gut flora may have something to say about your longevity.

C. elegans nematodes live in the laboratory fed on Escherichia coli, the common colon bacterium. Since the bacteria are the sole diet of the worms, to change the worm’s diet, mutant bacteria must be used. To study the impact of various vitamins on longevity, mutant bacteria unable to synthesize particular vitamins were fed to worms and their average length of life was measured.

Deleting coenzyme Q (10) resulted in a surprising increase in longevity. It was assumed that since coQ10 was needed for effective bacterial electron transport, the disruption would result in an increase in inflammatory ROS. What actually happened was that the bacteria shut down their use of aerobic metabolism and turned on fermentation.

Fermenting bacteria are probiotic in human guts and it appears that the same is true of worms. These results suggest that probiotic, fermenting gut flora may be profoundly important in determining longevity. What we eat may determine how long we keep eating.

reference:
Saiki R, Lunceford AL, Bixler T, Dang P, Lee W, Furukawa S, Larsen PL, Clarke CF. 2008. Altered bacterial metabolism, not coenzyme Q content, is responsible for the lifespan extension in Caenorhabditis elegans fed an Escherichia coli diet lacking coenzyme Q. Aging Cell. 7(3):291-304.