Visitors Now:
Total Visits:
Total Stories:

By ScienceBlogs (Reporter)
Contributor profile | More stories

Story Views
Now:
Last Hour:
Last 24 Hours:
Total:

Calorie restriction does not lengthen lifespan for primates [Life Lines]

Wednesday, September 5, 2012 18:32

% of readers think this story is Fact. Add your two cents.

(Before It's News)

: Although slimmer, calorie restricted rhesus monkeys (left) do not live longer than their age-matched counterparts (right). (Housing shown was for photo purposes only; Image: National Institutes of Aging; Austad SN, Nature 2012).

Despite promising results in mice and rats that calorie restriction prolongs lifespan, results from the US National Institute on Aging (NIA) in Bethesda, MD were just published in Nature last week and concluded that calorie restriction for primates had no effect on longevity.

In the study, young and old rhesus monkeys were fed either control diets or 30% reduced-calorie diets. For older males, calorie restriction had some health benefits in the form of lower cholesterol and triglycerides with moderately lower blood glucose than control animals. In contrast, young males started on the special diet showed no differences in blood glucose and only small improvements in triglycerides. Preliminary findings from the study also suggest that calorie restriction may just delay (but not prevent) the onset of age-related diseases like cancer and cardiovascular disease.

In a similar study of young rhesus monkeys (7-14 years old) at the Wisconsin National Primate Research Center, researchers found a trend towards longer lifespans for calorie restricted animals after they had discounted what they felt were not age-related deaths. This has led some experts in the field to suspect that the deaths in the restricted group may have been related to the treatment (roughly half of the total deaths were eliminated from their calculations) especially since there were a higher number of deaths that were termed non-age related in the calorie restricted group than the controls.

Another difference between the studies was diet composition with more sucrose included in the Wisconsin trial, which may be related to the higher incidence of diabetes in the control animals in that study as compared to the NIA study. An article by aging expert Dr. Austad suspected that the differences may be attributed to the type of calorie (fat, sugars, proteins) ingested as opposed to the quantity.

So much for finding the fountain of youth in dieting. This primate is going to enjoy some ice cream with fudge now…and sprinkles.

Source:

Austad SN. Ageing: Mixed results for dieting monkeys. Nature, August 29, 2012.

Maxmen A. Calorie restriction falters in the long run: Genetics and healthy diets matter more for longevity. Nature, August 29, 2012.

Mattison JA, Roth GS, Beasley TM, Tilmont EM, Handy AM, Herbert RL, Longo DL, Allison DB, Young JE, Bryant M, Barnard D, Ward WF, Qi W, Ingram DK, de Cabo R. Impact of caloric restriction on health and survival in rhesus monkeys from the NIA study. Nature. August 29, 2012. doi:10.1038/nature11432

2012-09-05 18:24:41

Source: http://scienceblogs.com/lifelines/2012/09/05/calorie-restriction-does-not-lengthen-lifespan-for-primates/

Source:

Comments

Newsletter

Email this story