Mouse Lifespan Will Be Extended Through Carefully Timed Calorie Restriction

Mouse Lifespan Will Be Extended Through Carefully Timed Calorie Restriction ...

The UT SouthwesternsPeter ODonnell Jr. Brain Institute has conducted a new study in mice. It shows that it does not only count calories.

According to experts, timing feedings to match the active period of the circadian cycle extended lab mice''s life span more than three times as much as caloric restriction alone.

According to Dr. Takahashi, the Distinguished Chair in Neuroscience at Loyd B. Sands, we have discovered a new facet to caloric restrictions that dramatically extends life span in lab animals. We might rethink whether or not we really want that midnight snack.

Their findings suggest that:

  • Mice that ate as much and whenever they wanted lived nearly 800 days median life span an average period for their species
  • Restricting calories but making food available around the clock extended their lives only 10% to 875 days despite restricting calories by 30-40%.
  • Restricting this reduced-calorie diet to the inactive period of the circadian cycle boosted lifespan by nearly 20% to an average of 959 days.
  • Offering the low-calorie diet only during the active period of the cycle extended their median life span to about 1,068 days, an increase of almost 35% over the unrestricted eaters.

According to Dr. Takahashi, one of the 26 members of the National Academy of Sciences and 17 members of the National Academy of Medicine at Southwestern, the timing of eating is important to get the most bang for your buck.

Despite the significant differences in life span, these research have found that while body weight was not affected by the pattern or time of eating.

This is why this popular health measure (body weight) is not a predictor of life span, according to Dr. Green, a Distinguished Scholar in Neuroscience at the University of Southwestern.

Mouse who lived the longest had significantly improved metabolic health, with increased insulin sensitivity and blood sugar stability. They tended to develop diseases that killed the younger mice, such as cancer, at significantly advanced ages. Gene expression studies showed fewer changes in the activity of genes associated with inflammation, metabolism, and aging in long-lived animals.

UC Southwestern''s expert says the findings provide a proof-of-principle for conducting circadian clocks as potential targets to delay ageing.

Disentangling the data

Dr. Takahashi said that experiments dating back to the 1930s have shown that lowering typical calorie counts by around a third extends life span as well as health span the length of time before diseases associated with old age arise in every species in which this phenomenon has been investigated. More recent research has shown that periods of fasting and restricting eating to active hours also boost health.

Most caloric restriction techniques have involved feeding lab mice which are nocturnal on a daytime schedule that matches their human caretakers. However, the UTSW team opted for automatic feeders to avoid that.

TheTakahashi LabandGreen Lab, along with colleagues, tracked the life span and health of six groups of mice for four years to disentangulate the effects of caloric restriction, fasting, and timing of meals on life span.

You may also like: